ALBERT

Description: Soils and landscapes are bridges of space and time, as they simultaneously and authentically show essential aspects that were previously separated by time and space (such as cultural and activity-related aspects from past and present) to the trained observer - albeit only in excerpts. Therefore, this article presents a series of impact indicators for soil changes, starting with extreme (anthropogenic) interventions and ending with equally extreme ("natural") events. An essential difference to specifically planning-relevant or human ecological concepts, which, for example, specify land use/load categories, is that the following impact indicators perceive soils as a phenomenon in themselves and do not define them through attributed functions. Particular attention is focused on their changeability and vital development potential, as well as on their property as a sphere of penetration of living and material things, with emphasis on the noetic effect. The intervention or event spaces on the earth's surface can be differentiated quantitatively through the type, strength, and duration of the phenomena. The intensity of all processes can be described by amplitude (the strength of the interventions/events) and frequency (the repetition rate of the interventions/events) and can be specifically identified and quantified by, for example, material inputs or outputs per unit of time. For the first time, there would be a system for measuring the ecological quality of anthropogenic land use, which could serve as an "alert system for the external technological culture," and could help us become aware of our "inner" culture.

Description: research

Description: We report the results of position ties for short baselines at eight geodetic sites based on phase delays that are extracted from global geodetic very‐long‐baseline interferometry (VLBI) observations rather than dedicated short‐baseline experiments. An analysis of phase delay observables at X band from two antennas at the Geodetic Observatory Wettzell, Germany, extracted from 107 global 24‐hr VLBI sessions since 2019 yields weighted root‐mean‐square scatters about the mean baseline vector of 0.3, 0.3, and 0.8 mm in the east, north, and up directions, respectively. Position ties are also obtained for other short baselines between legacy antennas and nearby, newly built antennas. They are critical for maintaining a consistent continuation of the realization of the terrestrial reference frame, especially when including the new VGOS network. The phase delays of the baseline WETTZ13N–WETTZELL enable an investigation of sources of error at the sub‐millimeter level. We found that a systematic variation of larger than 1 mm can be introduced to the Up estimates of this baseline vector when atmospheric delays were estimated. Although the sub‐millimeter repeatability has been achieved for the baseline vector WETTZ13N–WETTZELL, we conclude that long term monitoring should be conducted for more short baselines to assess the instrumental effects, in particular the systematic differences between phase delays and group delays, and to find common solutions for reducing them. This will be an important step toward the goal of global geodesy at the 1 mm level.

Description: Plain Language Summary: We report the results of position ties for short baselines at eight geodetic sites based on phase delays that are extracted from global geodetic very‐long‐baseline interferometry (VLBI) observations rather than dedicated short‐baseline experiments. By using the inherently more precise observables—phase delays, a baseline vector repeatability of WETTZ13N–WETTZELL has been achieved at the sub‐millimeter level for the horizontal directions and at the 1 mm level for the vertical direction based on VLBI experiments of 107 days during 3.5 years. Position ties based on phase delays are also obtained for other short baselines between legacy antennas and nearby, newly built antennas, and they are critical to maintain a consistent continuation of the realization of terrestrial reference frame into the future of a network of these new antennas. We have evaluated the instrumental stability at the 1 mm level, which is an important step toward the goal of global geodesy at this level.

Description: Key Points: Baseline vectors between legacy antennas and co‐located VGOS antennas are obtained from phase delays with the highest possible precision. Sources of error in short‐baseline observations are investigated at the 1 mm level in terms of their potential impacts.

Description: Academy of Finland http://dx.doi.org/10.13039/501100002341

Description: https://ivscc.gsfc.nasa.gov/productsdata/data.html

Description: https://sourceforge.net/projects/nusolve/

Description: Very Long Baseline Interferometry (VLBI) intensive (INT) sessions are critical for the rapid determination and densification of Universal Time 1‐Coordinate Universal Time (UT1‐UTC), which plays an important role in satellite geodesy and space exploration missions and is not predictable over longer time scales. Due to the limited observation geometry of INT sessions with two to three stations observing about 1 hr, tropospheric gradients cannot be estimated, which degrades the UT1‐UTC precision. We investigate the impact of tropospheric ties at Global Navigation Satellite Systems (GNSSs) and VLBI co‐located stations in INT sessions from 2001 to 2021. VLBI and GNSS observations are combined on the observation level. The results are evaluated by using both UT1‐UTC and Length of Day (LOD) from consecutive sessions. We demonstrate a better agreement of 10%–30% when comparing the derived LOD to GNSS LOD for INT1, INT2, and VGOS‐2 sessions; whereas, the agreement is not improved when directly comparing UT1‐UTC to the IERS Earth Orientation Parameters (EOPs) product, potentially because INT sessions also contribute to IERS EOP products. The major impact comes from tropospheric gradient ties, whereas applying zenith delay ties does not improve or even deteriorate UT1‐UTC agreement. Gradient ties also introduce systematic biases in UT1‐UTC by around −3 to −5 μs, except for the Russian INT sessions. Regression analysis shows that the east gradient introduces systematic effects in UT1‐UTC for sessions involving Germany and USA (Hawaii), whereas for Germany–Japan and Russian sessions, the north gradient also contributes systematically.

Description: Plain Language Summary: Universal Time 1‐Coordinate Universal Time (UT1‐UTC) gives the time difference of UT1, defined by Earth's rotation, and UTC, defined by atomic clocks. UT1‐UTC is essential for real‐time navigation and space exploration. The variation of the first‐order negative time derivative of UT1‐UTC, Length of Day (LOD), is induced by mass redistribution, including tides of the solid Earth and oceans, the liquid core of the Earth and atmospheric variation, and climate events such as El Niño. Very Long Baseline Interferometry (VLBI) observing active galactic nuclei is the only space geodetic technique that can determine UT1‐UTC unambiguously. The 1‐hr intensive (INT) sessions, designed for the rapid determination and densification of UT1‐UTC, are performed daily with two VLBI radio telescopes. Due to the limited observation geometry, tropospheric gradients cannot be modeled in INT sessions, deteriorating UT1‐UTC estimates. We demonstrate an improvement of 10%–30% in LOD by applying tropospheric ties at VLBI and Global Navigation Satellite Systems co‐locations, especially the tropospheric gradients ties. Tropospheric gradient ties also introduce a systematic effect of −3 to −5 μs on UT1‐UTC, especially the east gradient. Our study shows that tropospheric ties should be adopted in future VLBI analysis for optimal UT1‐UTC products.

Description: Key Points: Tropospheric ties are applied in a Global Navigation Satellite System–Very Long Baseline Interferometry (GNSS–VLBI) integrated solution analyzing VLBI intensive (INT) sessions from 2001 to 2021. Length of Day (LOD) of IVS INT sessions shows a better agreement by 10%–30% when compared to GNSS LOD product, mainly due to gradient ties. Gradient ties, especially the east one, introduce systematic biases of −3 to −5 μs in Universal Time 1‐Coordinate Universal Time of IVS INT sessions.

Description: Helmholtz OCPC Program

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: https://www.iers.org/IERS/EN/DataProducts/EarthOrientationData/eop.html

Description: http://doi.org/10.17616/R3RD2H

Description: To mitigate temporal aliasing effects in monthly mean global gravity fields from the GRACE and GRACE‐FO satellite tandem missions, both tidal and non‐tidal background models describing high‐frequency mass variability in atmosphere and oceans are needed. To quantify tides in the atmosphere, we exploit the higher spatial (31 km) and temporal (1 hr) resolution provided by the latest atmospheric ECMWF reanalysis, ERA5. The oceanic response to atmospheric tides is subsequently modeled with the general ocean circulation model MPIOM (in a recently revised TP10L40 configuration that includes the feedback of self‐attraction and loading to the momentum equations and has an improved bathymetry around Antarctica) as well as the shallow water model TiME (employing a much higher spatial resolution and more elaborate tidal dissipation than MPIOM). Both ocean models consider jointly the effects of atmospheric pressure variations and surface wind stress. We present the characteristics of 16 waves beating at frequencies in the 1–6 cpd band and find that TiME typically outperforms the corresponding results from MPIOM and also FES2014b as measured from comparisons with tide gauge data. Moreover, we note improvements in GRACE‐FO laser ranging interferometer range‐acceleration pre‐fit residuals when employing the ocean tide solutions from TiME, in particular, for the S1 spectral line with most notable improvements around Australia, India, and the northern part of South America.

Description: Plain Language Summary: In addition to many rather slow processes such as the melting of glaciers, rapid mass redistribution related to the weather also measurably affect the Earth's gravity field. The ability of monitoring liquid freshwater changes within the Earth system from the satellite gravity missions GRACE (2002–2017) and GRACE‐FO (since 2018) relies on accurate background models of mass variability in atmosphere and oceans for both tidal and non‐tidal processes. Atmospheric tides are primarily excited in the middle atmosphere by solar energy absorption at periods of 24 hr and its overtones. We find additional tidal signatures in the atmosphere excited by periodic deformations of both crust and sea‐surface of the Earth. We thus introduce here a new data set for the atmospheric tides and their corresponding oceanic response that features both more waves and higher accuracy than other background models previously used for the processing of GRACE and GRACE‐FO satellite gravimetry data.

Description: Key Points: Sixteen relevant tidal lines identified in hourly data from ERA5 atmospheric reanalysis. Dedicated simulations with a high‐resolution global hydrodynamic model to simulate ocean tides with atmospheric influence. New tidal models reduce pre‐fit residuals in GRACE‐FO Laser Ranging Interferometer data.

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: https://pypi.org/project/cdsapi/

Description: https://mpimet.mpg.de/en/science/models/mpi-esm/mpiom

Description: https://doi.org/10.5067/graod-1bg06

Description: For high‐resolution regional geodetic applications, the International Terrestrial Reference Frame (ITRF) is complemented by regional densifications. These are realized either as multi‐year solutions related to a tectonic plate (e.g., EUREF for Europe) or as epoch reference frames (ERFs) to capture nonlinear geophysical station motions caused by, for example, earthquakes or non‐tidal loading (e.g., SIRGAS for Latin America). These Global Navigation Satellite Systems (GNSS)‐only based regional reference frames have in common that their geodetic datum is aligned with the ITRF datum at a specific epoch. The consequence is that their origin represents the Earth's center of figure and does not coincide with the instantaneous center of mass. Here, we present studies on a direct geocentric realization of regional ERFs. We propose to realize the geodetic datum for each epoch by combining global GNSS, Satellite Laser Ranging, and Very Long Baseline Interferometry networks via measured local ties at co‐located sites. A uniformly distributed global GNSS network is used to realize the orientation via a no‐net‐rotation constraint with respect to the ITRF and is densified by the stations of the regional subnetwork. The developed combination and filtering strategy aims to guarantee a stable datum realization for each epoch‐wise solution. Validating our results against global reference frames and geophysical loading models relating to the Earth's centers of mass and figure, we show that the realized displacement time series are geocentric and reflect seasonal geophysical processes. As the approach does not need to rely on co‐location sites in the region of interest, it is conceptually transferable to other regions on the globe.

Description: Plain Language Summary: In today's world, precise ground, sea, and air navigation and the accurate monitoring of geophysical processes are vital. Precise coordinate reference frames make it possible to relate observed displacements to the Earth system. For different regions, these reference frames are materialized by dense networks of Global Navigation Satellite Systems (GNSS) stations with precisely determined position coordinates. It is crucial that the origin (defined to coincide with the Earth's center of mass), the scale (the realized unit of length), and the orientation (with respect to the Earth's crust) of the reference frame match their conventional definition. The realization of this so‐called “geodetic datum” for current conventional reference frames suffers from several deficiencies. We have developed a strategy for the precise weekly geocentric realization of regional reference frames. Coping with the changing and inhomogeneous distribution of stations by observing different space‐geodetic techniques, we developed and implemented a strategy to improve the long‐term stability of the solutions. We show that this approach allows for monitoring geophysical processes (loading and earthquakes) at low latency and overcomes the problems of existing realizations. The developed strategy is based on global networks and its effectiveness is demonstrated in Latin America; however, it can be applied to any region of the Earth.

Description: Key Points: Geocentric datum realization for regional epoch reference frames. Combination of space‐geodetic techniques at normal equation level. Long‐term stability of the geocentric datum stability by a filtering approach.

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: Die Jubiläumsschrift zum 75jährigen Bestehen der Deutschen Geophysikalischen Gesellschaft (DGG) enthält zahlreiche Beiträge von Mitgliedern zu vier Schwerpunkten: 1) Eine Aktualisierung der Geschichte der DGG vor allem zu den an Ereignissen reichen letzten 25 Jahren sowie Ergänzungen zu vorausgegangenen Darstellungen. 2) Die Darstellung der Geschichte geophysikalischer Institute und Institutionen in Deutschland inklusive eines Rückblicks auf das erfolgreiche Wirken ihrer verdienstvollen Persönlichkeiten. 3) Die Beschreibung einer Auswahl in der deutschen Geophysik angegangener Großprojekte der letzten 25 Jahre. 4) In Anlehnung an die Festschrift zum 50jährigen Gründungsjubiläum ist schließlich noch ein Kapitel zu geophysikalischen 'Detailthemen' ausgeführt. In ihm sind auch Beiträge enthalten, die Traditionslinien bzw. Arbeiten betreffen, die in der früheren DDR aufgenommen worden waren und z.T. keine direkte Fortsetzung an einer Nachfolgeinstitution gefunden haben.

Description: commemorativepublication

Description: Wird heute genug für die wissenschaftliche und technologische Steuerung des sich immer rasanter vollziehenden globalen und regionalen Wandels der Bio- und Geosphäre getan? Hat die internationale Gemeinschaft die Kraft zu einem sinnvollen, übergreifenden "Umwelt-Management"? Geophysik kann auf Grund ihrer interdisziplinären Stellung innerhalb der Naturwissenschaften und mit ihren vielfältigen Beziehungen zur Technik zum effizienten Einsatz der Kräfte und Mittel beitragen - in einer Zeit weltweiter sozialer, politischer und eben auch ökologischer Konflikte. Geophysik kann notwendige Prioritäten wissenschaftlich begründen und verfechten und somit helfen, weittragende und konsensfähige Entscheidungen vorzubereiten, um gesellschaftliche Akzeptanz und Unterstützung für die Politik zu erreichen. Die Deutsche Geophysikalische Gesellschaft - getragen von ihrer Verantwortung um den Beitrag der Geophysik für die gemeinsame Zukunft - wendet sich im 75. Jahr ihres Bestehens mit dieser Denkschrift an die Öffentlichkeit. Teil I enthält einen Überblick zur Spezifik, zur Stellung, zu den Zielen und zur Bedeutung der Geophysik. Im Teil II stellen führende Geophysiker ausgewählte Beispiele moderner geophysikalischer Forschung vor. Teil III ist statistisch angelegt und gibt einen kurzen Überblick zu den in Deutschland angesiedelten Institutionen geophysikalischer Lehre und Forschung. Die Denkschrift "Mit Geophysik in die Zukunft" will Politiker, Industrielle, Wissenschaftler, Vertreter der Medien und interessierte Bürger erreichen, um im Interesse des Gemeinwohls zu angemessener Wissenschaftsförderung und kluger Zukunftsgestaltung beizutragen.

Description: commemorativepublication

Description: DFG, SUB Göttingen

Description: The feasibility of precise real-time orbit determination of low earth orbit satellites using onboard GNSS observations is assessed using six months of flight data from the Sentinel-6A mission. Based on offline processing of dual-constellation pseudorange and carrier phase measurements as well as broadcast ephemerides in a sequential filter with a reduced dynamic force model, navigation solutions with a representative position error of 10 cm (3D RMS) are achieved. The overall performance is largely enabled by the superior quality of the Galileo broadcast ephemerides, which exhibits a two- to three-times smaller signal-in-space-range error than GPS and allows for geodetic-grade GNSS real-time orbit determination without a need for external correction services. Compared to GPS-only processing, a roughly two-times better navigation accuracy is achieved in a Galileo-only or mixed GPS/Galileo processing. On the other hand, GPS tracking offers a useful complement and additional robustness in view of a still incomplete Galileo constellation. Furthermore, it provides improved autonomy of the navigation process through the availability of earth orientation parameters in the new civil navigation message of the L2C signal. Overall, GNSS-based onboard orbit determination can now reach a similar performance as the DORIS (Doppler Orbitography and Radiopositioning Integrated by Satellite) navigation system. It lends itself as a viable alternative for future remote sensing missions.

Description: Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR) (4202)

Description: For more than 20 years, precise point positioning (PPP) has been a well-established technique for carrier phase-based navigation. Traditionally, it relies on precise orbit and clock products to achieve accuracies in the order of centimeters. With the modernization of legacy GNSS constellations and the introduction of new systems such as Galileo, a continued reduction in the signal-in-space range error (SISRE) can be observed. Supported by this fact, we analyze the feasibility and performance of PPP with broadcast ephemerides and observations of Galileo and GPS. Two different functional models for compensation of SISREs are assessed: process noise in the ambiguity states and the explicit estimation of a SISRE state for each channel. Tests performed with permanent reference stations show that the position can be estimated in kinematic conditions with an average three-dimensional (3D) root mean square (RMS) error of 29 cm for Galileo and 63 cm for GPS. Dual-constellation solutions can further improve the accuracy to 25 cm. Compared to standard algorithms without SISRE compensation, the proposed PPP approaches offer a 40% performance improvement for Galileo and 70% for GPS when working with broadcast ephemerides. An additional test with observations taken on a boat ride yielded 3D RMS accuracy of 39 cm for Galileo, 41 cm for GPS, and 27 cm for dual-constellation processing compared to a real-time kinematic reference solution. Compared to the use of process noise in the phase ambiguity estimation, the explicit estimation of SISRE states yields a slightly improved robustness and accuracy at the expense of increased algorithmic complexity. Overall, the test results demonstrate that the application of broadcast ephemerides in a PPP model is feasible with modern GNSS constellations and able to reach accuracies in the order of few decimeters when using proper SISRE compensation techniques.

Description: Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR) (4202)

Description: Solar radiation pressure (SRP) is the dominant non-gravitational perturbation for GPS satellites. In the IGS (International GNSS Service), this perturbation is modeled differently by individual analysis centers (ACs). The two most widely used methods are the Empirical CODE orbit Model (ECOM, ECOM2) and the JPL GSPM model. When using ECOM models, a box-wing model or other a priori models, as well as stochastic pulses at noon or midnight, are optionally adopted by some ACs to compensate for the deficiencies of the ECOM or ECOM2 model. However, both box-wing and GSPM parameters were published many years ago. There could be an aging effect going with time. Also, optical properties and GSPM parameters of GPS Block IIF satellites are currently not yet published. In this contribution, we first determine Block-specific optical parameters of GPS satellites using GPS code and phase measurements of 6 years. Various physical effects, such as yaw bias, radiator emission in the satellite body-fixed − X and Y directions and the thermal radiation of solar panels, are considered as additional constant parameters in the optical parameter adjustment. With all the adjusted parameters, we form an enhanced box-wing model adding all the modeled physical effects. In addition, we determine Block-specific GSPM parameters by using the same GPS measurements. The enhanced box-wing model and the GSPM model are then taken as a priori model and are jointly used with ECOM and ECOM2 model, respectively. We find that the enhanced box-wing model performs similarly to the GSPM model outside eclipse seasons. RMSs of all the ECOM and ECOM2 parameters are reduced by 30% compared to results without the a priori model. Orbit misclosures and orbit predictions are improved by combining the enhanced box-wing model with ECOM and ECOM2 models. In particular, the improvement in orbit misclosures for the eclipsing Block IIR and IIF satellites, as well as the non-eclipsing IIA satellites, is about 25%, 10% and 10%, respectively, for the ECOM model. Therefore, the enhanced box-wing model is recommended as an a priori model in GPS satellite orbit determination.

Description: Projekt DEAL

Description: Turkey, as a developing country, is designing and performing massive construction projects around Istanbul. Beginning from the 1960s, rapid urbanization has been taking place due to industrialization, which brings an increase in the population. Yet, construction projects have been accelerated especially during the last decade, and many new projects are scheduled to be completed in a short time. Ground-based observations are generally carried out to monitor the deformations within construction sites, especially through geometric levelling, and GNSS techniques. However, in most cases, these monitoring measurements are only scheduled within the period of the construction process, and ensuing deformations are usually not considered. In addition to these techniques, the space-based interferometric technique can also be used to define the line of sight surface displacements with high accuracy, using the phase difference between image result for synthetic aperture radar images. In particular, Persistent Scatter Interferometry is one of the interferometric methods that are capable of defining the two-dimensional (vertical and horizontal) deformation for the desired epoch with a high temporal resolution. Thus it can be used as a complementary method for monitoring ground deformations, where the measurement is made by ground-based observations. In this study, the deforming areas related to underground metro construction are investigated through significant displacements between 2015 and 2018 of Sentinel-1 space-borne SAR data using the PSI technique. These results are validated by comparison with available levelling data corresponding to the new metro line.

Description: Freie Universität Berlin (1008)

Description: After it was found that the gravity gradients observed by the Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellite could be significantly improved by an advanced calibration, a reprocessing project for the entire mission data set was initiated by ESA and performed by the GOCE High-level processing facility (GOCE HPF). One part of the activity was delivering the gravity field solutions, where the improved level 1b and level 2 data serve as an input for global gravity field recovery. One well-established approach for the analysis of GOCE observations is the so-called time-wise approach. Basic characteristics of the GOCE time-wise solutions is that only GOCE observations are included to remain independent of any other gravity field observables and that emphasis is put on the stochastic modeling of the observations’ uncertainties. As a consequence, the time-wise solutions provide a GOCE-only model and a realistic uncertainty description of the model in terms of the full covariance matrix of the model coefficients. Within this contribution, we review the GOCE time-wise approach and discuss the impact of the improved data and modeling applied in the computation of the new GO_CONS_EGM_TIM_RL06 solution. The model reflects the Earth’s static gravity field as observed by the GOCE satellite during its operation. As nearly all global gravity field models, it is represented as a spherical harmonic expansion, with maximum degree 300. The characteristics of the model and the contributing data are presented, and the internal consistency is demonstrated. The updated solution nicely meets the official GOCE mission requirements with a global mean accuracy of about 2 cm in terms of geoid height and 0.6 mGal in terms of gravity anomalies at ESA’s target spatial resolution of 100 km. Compared to its RL05 predecessor, three kinds of improvements are shown, i.e., (1) the mean global accuracy increases by 10–25%, (2) a more realistic uncertainty description and (3) a local reduction of systematic errors in the order of centimeters.

Description: European Space Agency http://dx.doi.org/10.13039/501100000844

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: Gauss Centre for Supercomputing e.V./John von Neumann Institute for Computing

Description: Projekt DEAL

Description: https://goce-ds.eo.esa.int/oads/access/

Description: Since Kepler, Newton and Huygens in the seventeenth century, geodesy has been concerned with determining the figure, orientation and gravitational field of the Earth. With the beginning of the space age in 1957, a new branch of geodesy was created, satellite geodesy. Only with satellites did geodesy become truly global. Oceans were no longer obstacles and the Earth as a whole could be observed and measured in consistent series of measurements. Of particular interest is the determination of the spatial structures and finally the temporal changes of the Earth's gravitational field. The knowledge of the gravitational field represents the natural bridge to the study of the physics of the Earth's interior, the circulation of our oceans and, more recently, the climate. Today, key findings on climate change are derived from the temporal changes in the gravitational field: on ice mass loss in Greenland and Antarctica, sea level rise and generally on changes in the global water cycle. This has only become possible with dedicated gravity satellite missions opening a method known as satellite gravimetry. In the first forty years of space age, satellite gravimetry was based on the analysis of the orbital motion of satellites. Due to the uneven distribution of observatories over the globe, the initially inaccurate measuring methods and the inadequacies of the evaluation models, the reconstruction of global models of the Earth's gravitational field was a great challenge. The transition from passive satellites for gravity field determination to satellites equipped with special sensor technology, which was initiated in the last decade of the twentieth century, brought decisive progress. In the chronological sequence of the launch of such new satellites, the history, mission objectives and measuring principles of the missions CHAMP, GRACE and GOCE flown since 2000 are outlined and essential scientific results of the individual missions are highlighted. The special features of the GRACE Follow-On Mission, which was launched in 2018, and the plans for a next generation of gravity field missions are also discussed.

Description: Helmholtz-Zentrum Potsdam Deutsches GeoForschungsZentrum - GFZ (4217)

Description: GNSS satellite and receiving antennas exhibit group delay variations (GDV), which affect code pseudorange measurements. Like antenna phase center variations, which affect phase measurements, they are frequency-dependent and vary with the direction of the transmitted and received signal. GNSS code observations contain the combined contributions of satellite and receiver antennas. If absolute GDV are available for the receiver antennas, absolute satellite GDV can be determined. In 2019, an extensive set of absolute receiver antenna GDV was published and, thus, it became feasible to estimate absolute satellite antenna GDV based on terrestrial observations. We used the absolute GDV of four selected receiver antenna types and observation data of globally distributed reference stations that employ these antenna types to determine absolute GDV for the GPS, GLONASS, Galileo, BeiDou, and QZSS satellite antennas. Besides BeiDou-2 satellites whose GDV are known to reach up to 1.5 m peak-to-peak, the GPS satellites show the largest GDV at frequencies L1 and L5 with up to 0.3 and 0.4 m peak-to-peak, respectively. They also show the largest satellite-to-satellite variations within a constellation. The GDV of GLONASS-M satellites reach up to 25 cm at frequency G1; Galileo satellites exhibit the largest GDV at frequency E6 with up to 20 cm; BeiDou-3 satellites show the largest GDV of around 15 cm at frequencies B1-2 and B3. Frequencies L2 of GPS IIIA, E1 of Galileo FOC, and B2a/B2b of BeiDou-3 satellites are the least affected. Their variations are below 10 cm.

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: Technische Universität Dresden (1019)

Description: To resolve undifferenced GNSS phase ambiguities, dedicated satellite products are needed, such as satellite orbits, clock offsets and biases. The International GNSS Service CNES/CLS analysis center provides satellite (HMW) Hatch-Melbourne-Wübbena bias and dedicated satellite clock products (including satellite phase bias), while the CODE analysis center provides satellite OSB (observable-specific-bias) and integer clock products. The CNES/CLS GPS satellite HMW bias products are determined by the Hatch-Melbourne-Wübbena (HMW) linear combination and aggregate both code (C1W, C2W) and phase (L1W, L2W) biases. By forming the HMW linear combination of CODE OSB corrections on the same signals, we compare CODE satellite HMW biases to those from CNES/CLS. The fractional part of GPS satellite HMW biases from both analysis centers are very close to each other, with a mean Root-Mean-Square (RMS) of differences of 0.01 wide-lane cycles. A direct comparison of satellite narrow-lane biases is not easily possible since satellite narrow-lane biases are correlated with satellite orbit and clock products, as well as with integer wide-lane ambiguities. Moreover, CNES/CLS provides no satellite narrow-lane biases but incorporates them into satellite clock offsets. Therefore, we compute differences of GPS satellite orbits, clock offsets, integer wide-lane ambiguities and narrow-lane biases (only for CODE products) between CODE and CNES/CLS products. The total difference of these terms for each satellite represents the difference of the narrow-lane bias by subtracting certain integer narrow-lane cycles. We call this total difference “narrow-lane” bias difference. We find that 3% of the narrow-lane biases from these two analysis centers during the experimental time period have differences larger than 0.05 narrow-lane cycles. In fact, this is mainly caused by one Block IIA satellite since satellite clock offsets of the IIA satellite cannot be well determined during eclipsing seasons. To show the application of both types of GPS products, we apply them for Sentinel-3 satellite orbit determination. The wide-lane fixing rates using both products are more than 98%, while the narrow-lane fixing rates are more than 95%. Ambiguity-fixed Sentinel-3 satellite orbits show clear improvement over float solutions. RMS of 6-h orbit overlaps improves by about a factor of two. Also, we observe similar improvements by comparing our Sentinel-3 orbit solutions to the external combined products. Standard deviation value of Satellite Laser Ranging residuals is reduced by more than 10% for Sentinel-3A and more than 15% for Sentinel-3B satellite by fixing ambiguities to integer values.

Description: Technische Universität München (1025)

Description: In recent strapdown airborne and shipborne gravimetry campaigns with servo accelerometers of the widely used Q-Flex type, results have been impaired by heading-dependent measurement errors. This paper shows that the effect is, in all likelihood, caused by the sensitivity of the Q-Flex type sensor to the Earth’s magnetic field. In order to assess the influence of magnetic fields on the utilised strapdown IMU of the type iMAR iNAV-RQH-1003, the IMU has been exposed to various magnetic fields of known directions and intensities in a 3-D Helmholtz coil. Based on the results, a calibration function for the vertical accelerometer is developed. At the example of five shipborne and airborne campaigns, it is outlined that under specific circumstances the precision of the gravimetry results can be strongly improved using the magnetic calibration approach: The non-adjusted RMSE at repeated lines decreased from 1.19 to 0.26 mGal at a shipborne campaign at Lake Müritz, Germany. To the knowledge of the authors, a significant influence of the Earth’s magnetic field on strapdown inertial gravimetry is demonstrated for the first time.

Description: Technische Universität Darmstadt (3139)

Description: The Sentinel-6 (or Jason-CS) altimetry mission provides a long-term extension of the Topex and Jason-1/2/3 missions for ocean surface topography monitoring. Analysis of altimeter data relies on highly-accurate knowledge of the orbital position and requires radial RMS orbit errors of less than 1.5 cm. For precise orbit determination (POD), the Sentinel-6A spacecraft is equipped with a dual-constellation GNSS receiver. We present the results of Sentinel-6A POD solutions for the first 6 months since launch and demonstrate a 1-cm consistency of ambiguity-fixed GPS-only and Galileo-only solutions with the dual-constellation product. A similar performance (1.3 cm 3D RMS) is achieved in the comparison of kinematic and reduced-dynamic orbits. While Galileo measurements exhibit 30–50% smaller RMS errors than those of GPS, the POD benefits most from the availability of an increased number of satellites in the combined dual-frequency solution. Considering obvious uncertainties in the pre-mission calibration of the GNSS receiver antenna, an independent inflight calibration of the phase centers for GPS and Galileo signal frequencies is required. As such, Galileo observations cannot provide independent scale information and the estimated orbital height is ultimately driven by the employed forces models and knowledge of the center-of-mass location within the spacecraft. Using satellite laser ranging (SLR) from selected high-performance stations, a better than 1 cm RMS consistency of SLR normal points with the GNSS-based orbits is obtained, which further improves to 6 mm RMS when adjusting site-specific corrections to station positions and ranging biases. For the radial orbit component, a bias of less than 1 mm is found from the SLR analysis relative to the mean height of 13 high-performance SLR stations. Overall, the reduced-dynamic orbit determination based on GPS and Galileo tracking is considered to readily meet the altimetry-related Sentinel-6 mission needs for RMS height errors of less than 1.5 cm.

Description: Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR) (4202)

Description: In this simulation study we analyze the benefit of ground-space optical two-way links (OTWL) for Galileo precise orbit determination (POD). OTWL is a concept based on continuous wave laser ranging and time transfer with modulated signals from and to ground stations. The measurements are in addition to Global Navigation Satellite System (GNSS) observations. We simulate the measurements with regard to 16 Galileo Sensor Stations. In the simulation study we assume that the whole Galileo satellite constellation is equipped with terminals for OTWL. Using OTWL together with Galileo L-band, in comparison with an orbit solution calculated with L-band-only, demonstrates the advantage of combining two ranging techniques with different influences of systematic errors. The two-way link allows a station and satellite clock synchronization. Furthermore, we compare the ground-space concept with the satellite-to-satellite counterpart known as optical two-way inter-satellite links (OISL). The advantage of OTWL is the connection between the satellite system and the solid Earth as well as the possibility to synchronize the satellite clocks and the ground station clocks. The full network, using all three observation types in combination is simulated as well. The possibility to estimate additional solar radiation pressure (SRP) parameters within these combinations is a clear benefit of these additional links. We paid great attention to simulate systematic effects of all observation techniques as realistically as possible. For L-band these are measurement noise, tropospheric delays, phase center variation of receiver and transmitter antennas, constant and variable biases as well as multipath. For optical links we simulated colored and distance-dependent noise, offsets due to the link repeatability and offsets related to the equipment calibration quality. In addition, we added a troposphere error for the OTWL measurements. We discuss the influence on the formal orbit uncertainties and the effects of the systematic errors. Restrictions due to weather conditions are addressed as well. OTWL is synergetic with the other measurement techniques like OISL and can be used for data transfer and communication, respectively.

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: Technische Universität München (1025)

Description: We present a partition-enhanced least-squares collocation (PE-LSC) which comprises several modifications to the classical LSC method. It is our goal to circumvent various problems of the practical application of LSC. While these investigations are focused on the modeling of the exterior gravity field the elaborated methods can also be used in other applications. One of the main drawbacks and current limitations of LSC is its high computational cost which grows cubically with the number of observation points. A common way to mitigate this problem is to tile the target area into sub-regions and solve each tile individually. This procedure assumes a certain locality of the LSC kernel functions which is generally not given and, therefore, results in fringe effects. To avoid this, it is proposed to localize the LSC kernels such that locality is preserved, and the estimated variances are not notably increased in comparison with the classical LSC method. Using global covariance models involves the calculation of a large number of Legendre polynomials which is usually a time-consuming task. Hence, to accelerate the creation of the covariance matrices, as an intermediate step we pre-calculate the covariance function on a two-dimensional grid of isotropic coordinates. Based on this grid, and under the assumption that the covariances are sufficiently smooth, the final covariance matrices are then obtained by a simple and fast interpolation algorithm. Applying the generalized multi-variate chain rule, also cross-covariance matrices among arbitrary linear spherical harmonic functionals can be obtained by this technique. Together with some further minor alterations these modifications are implemented in the PE-LSC method. The new PE-LSC is tested using selected data sets in Antarctica where altogether more than 800,000 observations are available for processing. In this case, PE-LSC yields a speed-up of computation time by a factor of about 55 (i.e., the computation needs only hours instead of weeks) in comparison with the classical unpartitioned LSC. Likewise, the memory requirement is reduced by a factor of about 360 (i.e., allocating memory in the order of GB instead of TB).

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: Technische Universität München (1025)

Description: In 2015, the International Association of Geodesy defined the International Height Reference System (IHRS) as the conventional gravity field-related global height system. The IHRS is a geopotential reference system co-rotating with the Earth. Coordinates of points or objects close to or on the Earth’s surface are given by geopotential numbers C(P) referring to an equipotential surface defined by the conventional value W0 = 62,636,853.4 m2 s−2, and geocentric Cartesian coordinates X referring to the International Terrestrial Reference System (ITRS). Current efforts concentrate on an accurate, consistent, and well-defined realisation of the IHRS to provide an international standard for the precise determination of physical coordinates worldwide. Accordingly, this study focuses on the strategy for the realisation of the IHRS; i.e. the establishment of the International Height Reference Frame (IHRF). Four main aspects are considered: (1) methods for the determination of IHRF physical coordinates; (2) standards and conventions needed to ensure consistency between the definition and the realisation of the reference system; (3) criteria for the IHRF reference network design and station selection; and (4) operational infrastructure to guarantee a reliable and long-term sustainability of the IHRF. A highlight of this work is the evaluation of different approaches for the determination and accuracy assessment of IHRF coordinates based on the existing resources, namely (1) global gravity models of high resolution, (2) precise regional gravity field modelling, and (3) vertical datum unification of the local height systems into the IHRF. After a detailed discussion of the advantages, current limitations, and possibilities of improvement in the coordinate determination using these options, we define a strategy for the establishment of the IHRF including data requirements, a set of minimum standards/conventions for the determination of potential coordinates, a first IHRF reference network configuration, and a proposal to create a component of the International Gravity Field Service (IGFS) dedicated to the maintenance and servicing of the IHRS/IHRF.

Description: https://www.ngs.noaa.gov/GRAV-D/data_ms05.shtml

Description: Ambiguity resolution of a single receiver is becoming more and more popular for precise GNSS (Global Navigation Satellite System) applications. To serve such an approach, dedicated satellite orbit, clock and bias products are needed. However, we need to be sure whether products based on specific frequencies and signals can be used when processing measurements of other frequencies and signals. For instance, for Galileo E5a frequency, some receivers track only the pilot signal (C5Q) while some track only the pilot-data signal (C5X). We cannot compute the differences between C5Q and C5X directly since these two signals are not tracked concurrently by any common receiver. As code measurements contribute equally as phase in the Melbourne-Wuebbena (MelWub) linear combination it is important to investigate whether C5Q and C5X can be mixed in a network to compute a common satellite MelWub bias product. By forming two network clusters tracking Q and X signals, respectively, we confirm that GPS C5Q and C5X signals cannot be mixed together. Because the bias differences between GPS C5Q and C5X can be more than half of one wide-lane cycle. Whereas, mixing of C5Q and C5X signals for Galileo satellites is possible. The RMS of satellite MelWub bias differences between Q and X cluster is about 0.01 wide-lane cycles for both E1/E5a and E1/E5b frequencies. Furthermore, we develop procedures to compute satellite integer clock and narrow-lane bias products using individual dual-frequency types. Same as the finding from previous studies, GPS satellite clock differences between L1/L2 and L1/L5 estimates exist and show a periodical behavior, with a peak-to-peak amplitude of 0.7 ns after removing the daily mean difference of each satellite. For Galileo satellites, the maximum clock difference between E1/E5a and E1/E5b estimates after removing the mean value is 0.04 ns and the mean RMS of differences is 0.015 ns. This is at the same level as the noise of the carrier phase measurement in the ionosphere-free linear combination. Finally, we introduce all the estimated GPS and Galileo satellite products into PPP-AR (precise point positioning, ambiguity resolution) and Sentinel-3A satellite orbit determination. Ambiguity fixed solutions show clear improvement over float solutions. The repeatability of five ground-station coordinates show an improvement of more than 30% in the east direction when using both GPS and Galileo products. The Sentinel-3A satellite tracks only GPS L1/L2 measurements. The standard deviation (STD) of satellite laser ranging (SLR) residuals is reduced by about 10% when fixing ambiguity parameters to integer values.

Description: Klinikum rechts der Isar der Technischen Universität München (8934)

Description: The increasing importance of terrestrial gravimetry in monitoring global change processes, in providing a reference for satellite measurements and in applications in metrology necessitates a stable reference system reflecting the measurement accuracy achievable by modern gravimeters. Therefore, over the last decade, the International Association of Geodesy (IAG) has developed a system to achieve accurate, homogeneous, long-term global recording of Earth’s gravity, while taking advantage of the potential of today’s absolute gravity measurements. The current status of the International Gravity Reference System and Frame is presented as worked out by the IAG Joint Working Group 2.1.1 “Establishment of a global absolute gravity reference system” during the period 2015–2019. Here, the system is defined by the instantaneous acceleration of free-fall, expressed in the International System of Units (SI) and a set of conventional corrections for the time-independent components of gravity effects. The frame as the systems realization includes a set of conventional temporal gravity corrections which represent a uniform set of minimum requirements. Measurements with absolute gravimeters, the traceability of which is ensured by comparisons and monitoring at reference stations, provide the basis of the frame. A global set of such stations providing absolute gravity values at the microgal level is the backbone of the frame. Core stations with at least one available space geodetic technique will provide a link to the terrestrial reference frame. Expanded facilities enabling instrumental verification as well as repeated regional and additional comparisons will complement key comparisons at the level of the International Committee for Weights and Measures (CIPM) and ensure a common reference and the traceability to the SI. To make the gravity reference system accessible to any user and to replace the previous IGSN71 network, an infrastructure based on absolute gravity observations needs to be built up. This requires the support of national agencies, which are encouraged to establish compatible first order gravity networks and to provide information about existing absolute gravity observations.

Description: Ministry of Education, Youth and Sports of the Czech Republic (MŠMT)

Description: Wide-lane (WL) uncalibrated phase delay (UPD) is usually derived from Melbourne–Wübbena (MW) linear combination and is a prerequisite in Global Navigation Satellite Systems (GNSS) precise point positioning (PPP) ambiguity resolution (AR). MW is a linear combination of pseudorange and phase, and the accuracy is limited by the larger pseudorange noise which is about one hundred times of the carrier phase noise. However, there exist inconsistent pseudorange biases which may have detrimental effect on the WL UPD estimation, and further degrade user-side ambiguity fixing. Currently, only the large part of pseudorange biases, e.g., the differential code bias (DCB), are available and corrected in PPP-AR, while the receiver-type-dependent biases have not yet been considered. Ignoring such kind of bias, which could be up to 20 cm, will cause the ambiguity fixing failure, or even worse, the incorrect ambiguity fixing. In this study, we demonstrate the receiver-type-dependent WL UPD biases and investigate their temporal and spatial stability, and further propose the method to precisely estimate these biases and apply the corrections to improve the user-side PPP-AR. Using a large data set of 1560 GNSS stations during a 30-day period, we demonstrate that the WL UPD deviations among different types of receivers can reach ± 0.3 cycles. It is also shown that such kind of deviations can be calibrated with a precision of about 0.03 cycles for all Global Positioning System (GPS) satellites. On the user side, ignoring the receiver-dependent UPD deviation can cause significant positioning error up to 10 cm. By correcting the deviations, the positioning performance can be improved by up to 50%, and the fixing rate can also be improved by 10%. This study demonstrates that for the precise and reliable PPP-AR, the receiver-dependent UPD deviations cannot be ignored and have to be handled.

Description: China Scholarship Council http://dx.doi.org/10.13039/501100004543

Description: Helmholtz-Zentrum Potsdam Deutsches GeoForschungsZentrum - GFZ (4217)

Description: ftp://geodesy.noaa.gov/cors/rinex/

Description: ftp://ftp.gfz-potsdam.de/GNSS/products/mgex/

Description: ftp://ftp.aiub.unibe.ch/CODE/

Description: The gravity field maps of the satellite gravimetry missions Gravity Recovery and Climate Experiment (GRACE ) and GRACE Follow-On are derived by means of precise orbit determination. The key observation is the biased inter-satellite range, which is measured primarily by a K-Band Ranging system (KBR) in GRACE and GRACE Follow-On. The GRACE Follow-On satellites are additionally equipped with a Laser Ranging Interferometer (LRI), which provides measurements with lower noise compared to the KBR. The biased range of KBR and LRI needs to be converted for gravity field recovery into an instantaneous range, i.e. the biased Euclidean distance between the satellites’ center-of-mass at the same time. One contributor to the difference between measured and instantaneous range arises due to the nonzero travel time of electro-magnetic waves between the spacecraft. We revisit the calculation of the light time correction (LTC) from first principles considering general relativistic effects and state-of-the-art models of Earth’s potential field. The novel analytical expressions for the LTC of KBR and LRI can circumvent numerical limitations of the classical approach. The dependency of the LTC on geopotential models and on the parameterization is studied, and afterwards the results are compared against the LTC provided in the official datasets of GRACE and GRACE Follow-On. It is shown that the new approach has a significantly lower noise, well below the instrument noise of current instruments, especially relevant for the LRI, and even if used with kinematic orbit products. This allows calculating the LTC accurate enough even for the next generation of gravimetric missions.

Description: Max-Planck-Gesellschaft http://dx.doi.org/10.13039/501100004189

Description: National Natural Science Foundation of China http://dx.doi.org/10.13039/501100001809

Description: Quick response in emergency situations is crucial, because any delay can result in dramatic consequences and potentially human losses. Therefore, many institutions/authorities are relying on development of strategies for emergency management, specially to have a quick response process using modern technologies like unmanned aerial vehicles. A key factor affecting this process is to have a quick geo-situation report of the emergency in real time, which reflects the current emergency situation and supports in right decision-making. Providing such geo-reports is still not an easy task because—in most cases—a priori known spatial data like map data (raster/vector) or geodatabases are outdated, and anyway would not provide an overview on the current situation. Therefore, this paper introduces a management methodology of spatial data focusing on enabling a free access and viewing the data of interest in real time and in situ to support emergency managers. The results of this work are twofold: on the one hand, an automated mechanism for spatial data synchronization and streaming was developed and on the other hand, a spatial data sharing concept was realized using web map tile service. For results assessment, an experimental framework through the joint research project ANKommEn (English acronym: Automated Navigation and Communication for Exploration) was implemented. The assessment procedure was achieved based on specific evaluation criteria like time consumption and performance and showed that the developed methodology can help in overcoming some of existing challenges and addressing the practically relevant questions concerning on the complexity in spatial data sharing and retrieval.

Description: Bundesministerium für Wirtschaft und Energie http://dx.doi.org/10.13039/501100006360

Description: Technische Universität Braunschweig (1042)

Description: The differential code biases (DCBs) of the global positioning system (GPS) receiver onboard low-Earth orbit (LEO) satellites are commonly estimated by a local spherical symmetry assumption together with the known GPS satellite DCBs from ground-based observations. Nowadays, more and more LEO satellites are equipped with GPS receivers for precise orbit determination, which provides a unique chance to estimate both satellite and receiver DCBs without any ground data. A new method to estimate the GPS satellite and receiver DCBs using a network of LEO receivers is proposed. A multi-layer mapping function (MF) is used to combine multi-LEO satellite data at varying orbit heights. First, model simulations are conducted to compare the vertical total electron content (VTEC) derived from the multi-layer MF and the reference VTEC obtained from the empirical ionosphere model International Reference Ionosphere and Global Core Plasmasphere Model. Second, GPS data are collected from five LEO missions, including ten receivers used to estimate both the satellite and receiver DCBs simultaneously with the multi-layer MF. The results show that the GPS satellite DCB solutions obtained from space-based data are consistent with ground-based solutions provided by the Centre for Orbit Determination in Europe. The proposed normalization procedure combining topside observations from different LEO missions has the potential to improve the accuracies of satellite DCBs of Global Navigation Satellite Systems as well as the receiver DCBs onboard LEO satellites, although the number of LEO missions and spatial–temporal coverage of topside observations are limited.

Description: National Natural Science Foundation of China http://dx.doi.org/10.13039/501100001809

Description: Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR) (4202)

Description: Future generations of global navigation satellite systems (GNSSs) can benefit from optical technologies. Especially optical clocks could back-up or replace the currently used microwave clocks, having the potential to improve GNSS position determination enabled by their lower frequency instabilities. Furthermore, optical clock technologies—in combination with optical inter-satellite links—enable new GNSS architectures, e.g., by synchronization of distant optical frequency references within the constellation using time and frequency transfer techniques. Optical frequency references based on Doppler-free spectroscopy of molecular iodine are seen as a promising candidate for a future GNSS optical clock. Compact and ruggedized setups have been developed, showing frequency instabilities at the 10–15 level for averaging times between 1 s and 10,000 s. We introduce optical clock technologies for applications in future GNSS and present the current status of our developments of iodine-based optical frequency references.

Description: DLR

Description: Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR) (4202)

Description: The given paper describes a method for automatic 3D reconstruction of bridges from cadastral footprints and airborne laser scanning point clouds. The reconstructed bridges are used to enrich 3D city models. Unlike roofs, decks of bridges are typically smooth without ridge lines or step edges. Therefore, established methods for roof reconstruction are not suitable for bridges. The standard description language for semantic city models is CityGML. This specification of the Open Geospatial Consortium assumes that surfaces are composed of planar polygons. The approximation of smooth decks by planar polygons is achieved by using a medial axis tree. Instead of the medial axis of the footprint, a modified medial axis is computed that does not consider counter bearing edges. The resulting tree represents centerline connections between all counter bearing edges and, in conjunction with filtered height values of a point cloud, serves as the basis for approximation with polygons. In addition to modeling decks, superstructures such as pylons and cables are also derived from the point cloud. For this purpose, planes carrying many superstructure points are detected using the Random Sampling Consensus Algorithm (RANSAC). Images are generated by projecting points onto these planes. Then, image processing methods are used to find connected contours that are extruded to form 3D objects. The presented method was successfully applied to all bridges of two German cities as well as to large bridges built over the Rhine River.

Description: Rockfall is a natural hazard in mountainous areas not to be underestimated. Mass activities differing in rock volume may cause considerable economic damage. Accomplishing qualitative appraisal of high-potential zones for rockfall is a first step towards implementing mitigation strategies. Nowadays, Geographical Information Systems (GIS) are the state-of-the-art tool for a fast and economic approach of identifying potential hazard zones rather than using conventional mapping with in-situ field data. Primarily, current research focuses on designing and implementing user-friendly tools delineating potential rockfall hazard zonation (RHZ). The constructed model examines triggering factors like slope, aspect, elevation, lithology, structural lineament, rainfall intensity, and seismic activity focal depth of a mountainous coastal region (Gulf of Aqaba, Egypt). The extracted geomorphological parameters were based on a high-resolution TanDEM-X Digital Elevation Model. The enhanced Landsat ETM + 7 was used to generate the lithological and structural lineament parameters, while the rainfall data were collected from NASA project tool. The zonation model was implemented by means of ESRI’s ArcGIS Pro ModelBuilder. Google Earth Pro orthophotos compared with the generated rockfall hazard zonation map indicate the potential RHZ with high reliability. The achieved results show that 15 % of the study area qualifies as a high rockfall hazard zone. As the RHZs generated by the model depend on the input data and the selected rating scores and weights, obtaining ground truth is essential to get a trustworthy result. Finally, this study recommends employing the built RHZ model on similar terrains worldwide to support decision-makers involving any sustainable development projects.

Description: Low-pass filters are commonly used for the processing of airborne gravity observations. In this paper, for the first time, we include the resulting correlations consistently in the functional and stochastic model of residual least-squares collocation. We demonstrate the necessity of removing high-frequency noise from airborne gravity observations, and derive corresponding parameters for a Gaussian low-pass filter. Thereby, we intend an optimal combination of terrestrial and airborne gravity observations in the mountainous area of Colorado. We validate the combination in the frame of our participation in ‘the 1 cm geoid experiment’. This regional geoid modeling inter-comparison exercise allows the calculation of a reference solution, which is defined as the mean value of 13 independent height anomaly results in this area. Our result performs among the best and with 7.5 mm shows the lowest standard deviation to the reference. From internal validation we furthermore conclude that the input from airborne and terrestrial gravity observations is consistent in large parts of the target area, but not necessarily in the highly mountainous areas. Therefore, the relative weighting between these two data sets turns out to be a main driver for the final result, and is an important factor in explaining the remaining differences between various height anomaly results in this experiment.

Description: Technische Universität München (1025)

Description: Currently, many commercial airline aircraft cannot perform three-dimensionally guided approaches based on satellite-based augmentation systems. We propose a system to rebroadcast the correction and integrity data via a data link as provided by the ground-based augmentation system such that aircraft equipped with a GPS landing system (GLS) can use the wide-area corrections and perform localizer performance with vertical guidance (LPV) approaches while maintaining the same level of integrity. In consequence, the system loses some availability and the time to alert is slightly increased. We build a prototype system and present data collected for one week, confirming technical feasibility. There is a loss of 5.3 percent of availability during a 1-week data collection cycle in which we compared our system to standalone LPV service. We tested our prototype with two commercially available GLS receivers with positive results and successfully demonstrated the functionality with a conventional Airbus 319 equipped with a standard GLS receiver.

Description: The GPS satellite transmitter antenna phase center offsets (PCOs) can be estimated in a global adjustment by constraining the ground station coordinates to the current International Terrestrial Reference Frame (ITRF). Therefore, the derived PCO values rest on the terrestrial scale parameter of the frame. Consequently, the PCO values transfer this scale to any subsequent GNSS solution. A method to derive scale-independent PCOs without introducing the terrestrial scale of the frame is the prerequisite to derive an independent GNSS scale factor that can contribute to the datum definition of the next ITRF realization. By fixing the Galileo satellite transmitter antenna PCOs to the ground calibrated values from the released metadata, the GPS satellite PCOs in the z-direction (z-PCO) and a GNSS-based terrestrial scale parameter can be determined in GPS + Galileo processing. An alternative method is based on the gravitational constraint on low earth orbiters (LEOs) in the integrated processing of GPS and LEOs. We determine the GPS z-PCO and the GNSS-based scale using both methods by including the current constellation of Galileo and the three LEOs of the Swarm mission. For the first time, direct comparison and crosscheck of the two methods are performed. They provide mean GPS z-PCO corrections of −186 ± 25 mm and −221 ± 37 mm with respect to the IGS values and +1.55 ± 0.22 ppb (parts per billion) and +1.72 ± 0.31 in the terrestrial scale with respect to the IGS14 reference frame. The results of both methods agree with each other with only small differences. Due to the larger number of Galileo observations, the Galileo-PCO-fixed method leads to more precise and stable results. In the joint processing of GPS + Galileo + Swarm in which both methods are applied, the constraint on Galileo dominates the results. We discuss and analyze how fixing either the Galileo transmitter antenna z-PCO or the Swarm receiver antenna z-PCO in the combined GPS + Galileo + Swarm processing propagates to the respective freely estimated z-PCO of Swarm and Galileo.

Description: Chinese Government Scholarship http://dx.doi.org/10.13039/501100010890

Description: Helmholtz-Zentrum Potsdam Deutsches GeoForschungsZentrum - GFZ (4217)

Description: Absolute gravimeters are used in geodesy, geophysics and physics for a wide spectrum of applications. Stable gravimetric measurements over timescales from several days to decades are required to provide relevant insight into geophysical processes. Users of absolute gravimeters participate in comparisons with a metrological reference in order to monitor the temporal stability of the instruments and determine the bias to that reference. However, since no measurement standard of higher-order accuracy currently exists, users of absolute gravimeters participate in key comparisons led by the International Committee for Weights and Measures. These comparisons provide the reference values of highest accuracy compared to the calibration against a single gravimeter operated at a metrological institute. The construction of stationary, large-scale atom interferometers paves the way for a new measurement standard in absolute gravimetry used as a reference with a potential stability up to 1 nm/s 2 at 1 s integration time. At the Leibniz University Hannover, we are currently building such a very long baseline atom interferometer with a 10-m-long interaction zone. The knowledge of local gravity and its gradient along and around the baseline is required to establish the instrument’s uncertainty budget and enable transfers of gravimetric measurements to nearby devices for comparison and calibration purposes. We therefore established a control network for relative gravimeters and repeatedly measured its connections during the construction of the atom interferometer. We additionally developed a 3D model of the host building to investigate the self-attraction effect and studied the impact of mass changes due to groundwater hydrology on the gravity field around the reference instrument. The gravitational effect from the building 3D model is in excellent agreement with the latest gravimetric measurement campaign which opens the possibility to transfer gravity values with an uncertainty below the 10 nm/s2 level.

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: Bundesministerium für Bildung und Forschung http://dx.doi.org/10.13039/501100002347

Description: Niedersächsisches Ministerium für Wissenschaft und Kultur http://dx.doi.org/10.13039/501100010570

Description: https://www.bipm.org/kcdb

Description: XGM2019e is a combined global gravity field model represented by spheroidal harmonics up to degree and order (d/o) 5399, corresponding to a spatial resolution of 2′ (~ 4 km). As data sources, it includes the satellite model GOCO06s in the longer wavelength range up to d/o 300 combined with a ground gravity grid which also covers the shorter wavelengths. The ground data consist over land and ocean of gravity anomalies provided by courtesy of NGA (15′ resolution, identical to XGM2016) augmented with topographically derived gravity information over land (EARTH2014). Over the oceans, gravity anomalies derived from satellite altimetry are used (DTU13 with a resolution of 1′). The combination of the satellite data with the ground gravity observations is performed by using full normal equations up to d/o 719 (15′). Beyond d/o 719, a block-diagonal least squares solution is calculated for the high-resolution ground gravity data (from topography and altimetry). All calculations are performed in the spheroidal harmonic domain. In the spectral band up to d/o 719, the new model shows a slightly improved behaviour in the magnitude of a few mm RMS over land as compared to preceding models such as XGM2016, EIGEN6c4 or EGM2008 when validated with independent geoid information derived from GNSS/levelling. Over land and in the spectral range above d/o 719, the accuracy of XGM2019e marginally suffers from the sole use of topographic forward modelling, and geoid differences at GNSS/levelling stations are increased in the order of several mm RMS in well-surveyed areas, such as the US and Europe, compared to models containing real gravity data over their entire spectrum, e.g. EIGEN6c4 or EGM2008. However, GNSS/levelling validation also indicates that the performance of XGM2019e can be considered as globally more consistent and independent of existing high-resolution global models. Over the oceans, the model exhibits an enhanced performance (equal or better than preceding models), which is confirmed by comparison of the MDT’s computed from CNES/CLS 2015 mean sea surface and the high-resolution geoid models. The MDT based on XGM2019e shows fewer artefacts, particularly in the coastal regions, and fits globally better to DTU17MDT which is considered as an independent reference MDT.

Description: European Space Agency http://dx.doi.org/10.13039/501100000844

Description: The iteratively reweighted least-squares approach to self-tuning robust adjustment of parameters in linear regression models with autoregressive (AR) and t-distributed random errors, previously established in Kargoll et al. (in J Geod 92(3):271–297, 2018. https://doi.org/10.1007/s00190-017-1062-6), is extended to multivariate approaches. Multivariate models are used to describe the behavior of multiple observables measured contemporaneously. The proposed approaches allow for the modeling of both auto- and cross-correlations through a vector-autoregressive (VAR) process, where the components of the white-noise input vector are modeled at every time instance either as stochastically independent t-distributed (herein called “stochastic model A”) or as multivariate t-distributed random variables (herein called “stochastic model B”). Both stochastic models are complementary in the sense that the former allows for group-specific degrees of freedom (df) of the t-distributions (thus, sensor-component-specific tail or outlier characteristics) but not for correlations within each white-noise vector, whereas the latter allows for such correlations but not for different dfs. Within the observation equations, nonlinear (differentiable) regression models are generally allowed for. Two different generalized expectation maximization (GEM) algorithms are derived to estimate the regression model parameters jointly with the VAR coefficients, the variance components (in case of stochastic model A) or the cofactor matrix (for stochastic model B), and the df(s). To enable the validation of the fitted VAR model and the selection of the best model order, the multivariate portmanteau test and Akaike’s information criterion are applied. The performance of the algorithms and of the white noise test is evaluated by means of Monte Carlo simulations. Furthermore, the suitability of one of the proposed models and the corresponding GEM algorithm is investigated within a case study involving the multivariate modeling and adjustment of time-series data at four GPS stations in the EUREF Permanent Network (EPN).

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: For low Earth orbit (LEO) satellites, activities such as precise orbit determination, gravity field retrieval, and thermospheric density estimation from accelerometry require modeled accelerations due to radiation pressure. To overcome inconsistencies and better understand the propagation of modeling errors into estimates, we here suggest to extend the standard analytical LEO radiation pressure model with emphasis on removing systematic errors in time-dependent radiation data products for the Sun and the Earth. Our extended unified model of Earth radiation pressure accelerations is based on hourly CERES SYN1deg data of the Earth’s outgoing radiation combined with angular distribution models. We apply this approach to the GRACE (Gravity Recovery and Climate Experiment) data. Validations with 1 year of calibrated accelerometer measurements suggest that the proposed model extension reduces RMS fits between 5 and 27%, depending on how measurements were calibrated. In contrast, we find little changes when implementing, e.g., thermal reradiation or anisotropic reflection at the satellite’s surface. The refined model can be adopted to any satellite, but insufficient knowledge of geometry and in particular surface properties remains a limitation. In an inverse approach, we therefore parametrize various combinations of possible systematic errors to investigate estimability and understand correlations of remaining inconsistencies. Using GRACE-A accelerometry data, we solve for corrections of material coefficients and CERES fluxes separately over ocean and land. These results are encouraging and suggest that certain physical radiation pressure model parameters could indeed be determined from satellite accelerometry data.

Description: Deutsches Zentrum für Luft- und Raumfahrt http://dx.doi.org/10.13039/501100002946

Description: ftp://ftp.tugraz.at/outgoing/ITSG/tvgogo/orbits/GRACE/

Description: ftp://podaac-ftp.jpl.nasa.gov/allData/grace/L1B/JPL/

Description: Quantum optical technology provides an opportunity to develop new kinds of gravity sensors and to enable novel measurement concepts for gravimetry. Two candidates are considered in this study: the cold atom interferometry (CAI) gradiometer and optical clocks. Both sensors show a high sensitivity and long-term stability. They are assumed on board of a low-orbit satellite like gravity field and steady-state ocean circulation explorer (GOCE) and gravity recovery and climate experiment (GRACE) to determine the Earth’s gravity field. Their individual contributions were assessed through closed-loop simulations which rigorously mapped the sensors’ sensitivities to the gravity field coefficients. Clocks, which can directly obtain the gravity potential (differences) through frequency comparison, show a high sensitivity to the very long-wavelength gravity field. In the GRACE orbit, clocks with an uncertainty level of 1.0 × 10−18 are capable to retrieve temporal gravity signals below degree 12, while 1.0 × 10−17 clocks are useful for detecting the signals of degree 2 only. However, it poses challenges for clocks to achieve such uncertainties in a short time. In space, the CAI gradiometer is expected to have its ultimate sensitivity and a remarkable stability over a long time (measurements are precise down to very low frequencies). The three diagonal gravity gradients can properly be measured by CAI gradiometry with a same noise level of 5.0 mE/√Hz. They can potentially lead to a 2–5 times better solution of the static gravity field than that of GOCE above degree and order 50, where the GOCE solution is mainly dominated by the gradient measurements. In the lower degree part, benefits from CAI gradiometry are still visible, but there, solutions from GRACE-like missions are superior.

Description: Deutsche Forschungsgemeinschaft

Description: http://icgem.gfz-potsdam.de/tom_longtime

Description: https://earth.esa.int/web/guest/-/goce-data-access-7219

Description: ftp://podaac.jpl.nasa.gov/allData/grace/L1B/JPL/

Description: In the analysis of very long baseline interferometry (VLBI) observations, many geophysical models are used for correcting the theoretical signal delay. In addition to the conventional models described by Petit and Luzum (eds) (IERS Conventions, 2010), we are applying different parts of non-tidal site loading, namely the atmospheric, oceanic, and hydrological ones. To investigate their individual contributions, these parts are considered both separately and combined to a total loading. The application of the corresponding site displacements is performed at two distinct levels of the geodetic parameter estimation process (observation and normal equation level), which turn out to give very similar results in many cases. To validate our findings internally, the site displacements are provided by two different data centres: the Earth-System-Modelling group at the Deutsches GeoForschungsZentrum in Potsdam (ESMGFZ, see Dill and Dobslaw, J Geophys Res Solid Earth, 2013. https://doi.org/10.1002/jgrb.50353)] and the International Mass Loading Service [IMLS, see Petrov (The international mass loading service, 2015)]. We show that considering non-tidal loading is actually useful for mitigating systematic effects in the VLBI results, like annual signals in the station height time series. If the sum of all non-tidal loading parts is considered, the WRMS of the station heights and baseline lengths is reduced in 80–90% of all cases, and the relative improvement is about − 3.5% on average. The main differences between our chosen providers originate from hydrological loading.

Description: Technische Universität München (1025)

Description: ftp://cddis.nasa.gov/vlbi/ivsdata/vgosdb/

Description: http://rz-vm115.gfz-potsdam.de:8080/repository

Description: Satellite altimetry has been widely used to determine surface elevation changes in polar ice sheets. The original height measurements are irregularly distributed in space and time. Gridded surface elevation changes are commonly derived by repeat altimetry analysis (RAA) and subsequent spatial interpolation of height change estimates. This article assesses how methodological choices related to those two steps affect the accuracy of surface elevation changes, and how well this accuracy is represented by formal uncertainties. In a simulation environment resembling CryoSat-2 measurements acquired over a region in northeast Greenland between December 2010 and January 2014, different local topography modeling approaches and different cell sizes for RAA, and four interpolation approaches are tested. Among the simulated cases, the choice of either favorable or unfavorable RAA affects the accuracy of results by about a factor of 6, and the different accuracy levels are propagated into the results of interpolation. For RAA, correcting local topography by an external digital elevation model (DEM) is best, if a very precise DEM is available, which is not always the case. Yet the best DEM-independent local topography correction (nine-parameter model within a 3,000 m diameter cell) is comparable to the use of a perfect DEM, which exactly represents the ice sheet topography, on the same cell size. Interpolation by heterogeneous measurement-error-filtered kriging is significantly more accurate (on the order of 50% error reduction) than interpolation methods, which do not account for heterogeneous errors.

Description: German Research Foundation

Description: This study presents a solution of the ‘1 cm Geoid Experiment’ (Colorado Experiment) using spherical radial basis functions (SRBFs). As the only group using SRBFs among the fourteen participated institutions from all over the world, we highlight the methodology of SRBFs in this paper. Detailed explanations are given regarding the settings of the four most important factors that influence the performance of SRBFs in gravity field modeling, namely (1) the choosing bandwidth, (2) the locations of the SRBFs, (3) the type of the SRBFs as well as (4) the extensions of the data zone for reducing the edge effect. Two types of basis functions covering the same spectral range are used for the terrestrial and the airborne measurements, respectively. The non-smoothing Shannon function is applied to the terrestrial data to avoid the loss of spectral information. The cubic polynomial (CuP) function which has smoothing features is applied to the airborne data as a low-pass filter for filtering the high-frequency noise. Although the idea of combining different SRBFs for different observations was proven in theory to be possible, it is applied to real data for the first time, in this study. The RMS error of our height anomaly result along the GSVS17 benchmarks w.r.t the validation data (which is the mean results of the other contributions in the ‘Colorado Experiment’) drops by 5% when combining the Shannon function for the terrestrial data and the CuP function for the airborne data, compared to those obtained by using the Shannon function for both the two data sets. This improvement indicates the validity and benefits of using different SRBFs for different observation types. Global gravity model (GGM), topographic model, the terrestrial gravity data, as well as the airborne gravity data are combined, and the contribution of each data set to the final solution is discussed. By adding the terrestrial data to the GGM and the topographic model, the RMS error of the height anomaly result w.r.t the validation data drops from 4 to 1.8 cm, and it is further reduced to 1 cm by including the airborne data. Comparisons with the mean results of all the contributions show that our height anomaly and geoid height solutions at the GSVS17 benchmarks have an RMS error of 1.0 cm and 1.3 cm, respectively; and our height anomaly results give an RMS value of 1.6 cm in the whole study area, which are all the smallest among the participants.

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: In 2016, an application programming interface was added to the Android operating systems, which enables the access of GNSS raw observations. Since then, an in-depth evaluation of the performance of smartphone GNSS chips is very much simplified. We analyzed the quality of the GNSS observations, especially the carrier phase observations, of the dual-frequency GNSS chip Kirin 980 built into Huawei P30 and other smartphones. More than 80 h of static observations were collected at several locations. The code and carrier phase observations were processed in baseline mode with reference to observations of geodetic-grade equipment. We were able to fix carrier phase ambiguities for GPS L1 observations. Furthermore, we performed an antenna calibration for this frequency, which revealed that the horizontal phase center offsets from the central vertical axis of the smartphone and also the phase center variations do not exceed 1–2 cm. After successful ambiguity fixing, the 3D position errors (standard deviations) are smaller 4 cm after 5 min of static observation session and 2 cm for long observation session.

Description: Along with the rapid development of GNSS, not only BeiDou, but also Galileo, and the newly launched GPS satellites can provide signals on three frequencies at present. To fully take advantage of the multi-frequency multi-system GNSS observations on precise point positioning (PPP) technology, this study aims to implement the triple-frequency ambiguity resolution (AR) for GPS, Galileo, and BeiDou-2 combined PPP using the raw observation model. The processing of inter-frequency clock bias (IFCB) estimation and correction in the context of triple-frequency PPP AR has been addressed, with which the triple-frequency uncalibrated phase delay (UPD) estimation is realized for real GPS observations for the first time. In addition, the GPS extra-wide-line UPD quality is significantly improved with the IFCB correction. Because of not being contaminated by the IFCB, the raw UPD estimation method is directly employed for Galileo which currently has 24 satellites in operation. An interesting phenomenon is found that all Galileo satellites except E24 have a zero extra-wide-lane UPD value. With the multi-GNSS observations provided by MGEX covering 15 days, the positioning solutions of GPS + Galileo + BeiDou triple-frequency PPP AR have been conducted and analyzed. The triple-frequency kinematic GNSS PPP AR can achieve an averaged 3D positioning error of 2.2 cm, and an averaged convergence time of 10.8 min. The average convergence time can be reduced by triple-frequency GNSS PPP AR by 15.6% compared with dual-frequency GNSS PPP AR, respectively. However, the additional third frequency has only a marginal contribution to positioning accuracy after convergence.

Description: China National Funds for Distinguished Young Scientists http://dx.doi.org/10.13039/501100005153

Description: The use of the GLONASS legacy signals for real-time kinematic positioning is considered. Due to the FDMA multiplexing scheme, the conventional CDMA observation model has to be modified to restore the integer estimability of the ambiguities. This modification has a strong impact on positioning capabilities. In particular, the ambiguity resolution performance of this model is clearly weaker than for CDMA systems, so that fast and reliable full ambiguity resolution is usually not feasible for standalone GLONASS, and adding GLONASS data in a multi-GNSS approach can reduce the ambiguity resolution performance of the combined model. Partial ambiguity resolution was demonstrated to be a suitable tool to overcome this weakness (Teunissen in GPS Solut 23(4):100, 2019). We provide an exhaustive formal analysis of the positioning precision and ambiguity resolution capabilities for short, medium, and long baselines in a multi-GNSS environment with GPS, Galileo, BeiDou, QZSS, and GLONASS. Simulations are used to show that with a difference test-based partial ambiguity resolution method, adding GLONASS data improves the positioning performance in all considered cases. Real data from different baselines are used to verify these findings. When using all five available systems, instantaneous centimeter-level positioning is possible on an 88.5 km baseline with the ionosphere weighted model, and on average, only 3.27 epochs are required for a long baseline with the ionosphere float model, thereby enabling near instantaneous solutions.

Description: Helmholtz-Zentrum Potsdam Deutsches GeoForschungsZentrum - GFZ (4217)

Description: https://saegnss2.curtin.edu/ldc/

Description: ftp://cddis.gsfc.nasa.gov/gnss/data/

Description: ftp://ftp.gfz-potsdam.de/GNSS/products/mgex/

Description: Miniaturized atomic clocks with high frequency stability as local oscillators in global navigation satellite system (GNSS) receivers promise to improve real-time kinematic applications. For a number of years, such oscillators are being investigated regarding their overall technical applicability, i.e., transportability, and performance in dynamic environments. The short-term frequency stability of these clocks is usually specified by the manufacturer, being valid for stationary applications. Since the performance of most oscillators is likely degraded in dynamic conditions, various oscillators are tested to find the limits of receiver clock modeling in dynamic cases and consequently derive adequate stochastic models to be used in navigation. We present the performance of three different oscillators (Microsemi MAC SA.35m, Spectratime LCR-900 and Stanford Research Systems SC10) for static and dynamic applications. For the static case, all three oscillators are characterized in terms of their frequency stability at Physikalisch-Technische Bundesanstalt, Germany's national metrology institute. The resulting Allan deviations agree well with the manufacturer's data. Furthermore, a flight experiment was conducted in order to evaluate the performance of the oscillators under dynamic conditions. Here, each oscillator is replacing the internal oscillator of a geodetic-grade GNSS receiver and the stability of the receiver clock biases is determined. The time and frequency offsets of the oscillators are characterized with regard to the flight dynamics recorded by a navigation-grade inertial measurement unit. The results of the experiment show that the frequency stability of each oscillator is degraded by about at least one order of magnitude compared to the static case. Also, the two quartz oscillators show a significant g-sensitivity resulting in frequency shifts of − 1.2 × 10−9 and + 1.5 × 10−9, respectively, while the rubidium clocks are less sensitive, thus enabling receiver clock modeling and strengthening of the navigation performance even in high dynamics.

Description: Bundesministerium für Wirtschaft und Energie http://dx.doi.org/10.13039/501100006360

Description: Gottfried Wilhelm Leibniz Universität Hannover (1038)

Description: Global navigation satellite system (GNSS) remote sensing of the troposphere, called GNSS meteorology, is already a well-established tool in post-processing applications. Real-time GNSS meteorology has been possible since 2013, when the International GNSS Service (IGS) established its real-time service. The reported accuracy of the real-time zenith total delay (ZTD) has not improved significantly over time and usually remains at the level of 5–18 mm, depending on the station and test period studied. Millimeter-level improvements are noticed due to GPS ambiguity resolution, gradient estimation, or multi-GNSS processing. However, neither are these achievements combined in a single processing strategy, nor is the impact of other processing parameters on ZTD accuracy analyzed. Therefore, we discuss these shortcomings in detail and present a comprehensive analysis of the sensitivity of real-time ZTD on processing parameters. First, we identify a so-called common strategy, which combines processing parameters that are identified to be the most popular among published papers on the topic. We question the popular elevation-dependent weighting function and introduce an alternative one. We investigate the impact of selected processing parameters, i.e., PPP functional model, GNSS selection and combination, inter-system weighting, elevation-dependent weighting function, and gradient estimation. We define an advanced strategy dedicated to real-time GNSS meteorology, which is superior to the common one. The a posteriori error of estimated ZTD is reduced by 41%. The accuracy of ZTD estimates with the proposed strategy is improved by 17% with respect to the IGS final products and varies over stations from 5.4 to 10.1 mm. Finally, we confirm the latitude dependency of ZTD accuracy, but also detect its seasonality.

Description: H2020 Marie Skłodowska-Curie Actions http://dx.doi.org/10.13039/100010665

Description: GPS Block IIF satellites are able to redistribute the transmit power between the signal components. This ability is called flex power, and it has been developed as a remedy against jamming. Since it is operationally not possible to increase the transmit power for all signal components simultaneously, a redistribution between them is necessary under certain operational situations. Flex power has been active on Block IIF satellites since January 2017 over a specific regional area and has an impact on differential code bias estimation as well as the signal-to-noise density ratio. A network of the International GNSS Service stations containing only Septentrio PolaRx5 and PolaRx5TR receivers between August 1 and November 21, 2019 has been used for differential code bias estimation using GPS L1 C/A, L1 P(Y), L2 P(Y), and L2C signals with and without consideration of the flex power in the estimation process for Block IIF satellites. The estimation results are compared with the German Aerospace Center as well as the Chinese Academy of Sciences DCB products to validate the results.

Description: The access to Android-based Global Navigation Satellite Systems (GNSS) raw measurements has become a strong motivation to investigate the feasibility of smartphone-based positioning. Since the beginning of this research, the smartphone GNSS antenna has been recognized as one of the main limitations. Besides multipath (MP), the radiation pattern of the antenna is the main site-dependent error source of GNSS observations. An absolute antenna calibration has been performed for the dual-frequency Huawei Mate20X. Antenna phase center offset (PCO) and variations (PCV) have been estimated to correct for antenna impact on the L1 and L5 phase observations. Accordingly, we show the relevance of considering the individual PCO and PCV for the two frequencies. The PCV patterns indicate absolute values up to 2 cm and 4 cm for L1 and L5, respectively. The impact of antenna corrections has been assessed in different multipath environments using a high-accuracy positioning algorithm employing an undifferenced observation model and applying ambiguity resolution. Successful ambiguity resolution is shown for a smartphone placed in a low multipath environment on the ground of a soccer field. For a rooftop open-sky test case with large multipath, ambiguity resolution was successful in 19 out of 35 data sets. Overall, the antenna calibration is demonstrated being an asset for smartphone-based positioning with ambiguity resolution, showing cm-level 2D root mean square error (RMSE).

Description: Gottfried Wilhelm Leibniz Universität Hannover (1038)

Description: The realization of Coordinated Universal Time, one of the tasks of the International Bureau of Weights and Measures, relies on a network of international time links which currently is organized in a star-like scheme that links all contributing laboratories. GPS signal reception is the technique most widely employed by the laboratories. The PTB currently plays a unique role in the process due to its function as the central pivot in the time transfer between the participating laboratories. We discuss how the PTB meets its obligations to the international timekeeping community as well as to its users in Germany. In its role as an National Metrology Institute (NMI), PTB is entrusted with the realization and dissemination of legal time in Germany. The services were offered to the public support measurements and timing applications traceable to the national and international standards to be made in calibration laboratories and in many industrial sectors. We thus discuss the meaning and definition of traceability, how different GNSS systems can be used to establish traceability and their performance in doing so.

Description: During the last few years, the determination of high-resolution global gravity field has gained momentum due to high-accuracy satellite-derived observations and development of forward gravity modelling. Forward modelling computes the global gravitational field from mass distribution sources instead of actual gravity measurements and helps improving and complementing the medium to high-frequency components of the global gravity field models. In this study, we approximate the global gravity potential of the Earth’s upper crust based on ellipsoidal approximation and a mass layer concept. Such an approach has an advantage of spectral methods and also avoids possible instabilities due to the use of a sequence of thin ellipsoidal shells. Lateral density within these volumetric shells bounded by confocal lower and upper shell ellipsoids is used in the computation of the ellipsoidal harmonic coefficients which are then transformed into spherical harmonic coefficients on the Earth’s surface in the final step. The main outcome of this research is a spectral representation of the gravitatioal potential of the Earth’s upper crust, computed up to degree and order 3660 in terms of spherical harmonic coefficients (ROLI_EllApprox_SphN_3660). We evaluate our methodology by comparing this model with other similar forward models in the literature which show sub-cm agreement in terms of geoid undulations. Finally, EIGEN-6C4 is augmented by ROLI_EllApprox_SphN_3660 and the gravity field functionals computed from the expanded model which has about 5 km half-wavelength spatial resolution are compared w.r.t. ground-truth data in different regions worldwide. Our investigations show that the contribution of the topographic model increases the agreement up to ~ 20% in the gravity value comparisons.

Description: Tidal ecosystems like the Wadden Sea are particularly valuable for their ecological and economic importance. Here, the natural dynamics of the abiotic and biotic processes is threatened by the human pressure, and great efforts are made on mapping and monitoring programs. Remote sensing techniques (e.g., satellite and airborne sources) are commonly used on land and intertidal areas, whereas hydroacoustic devices are deployed in the subtidal zones. The overlap of hydroacoustics (sidescan sonar) and airborne Lidar data in such sensitive transitional zone (inter- to subtidal) is rather uncommon. In order to test the limitations of both techniques in extremely shallow waters (0.7 m min, water depth) and to find the most efficient methods for the spatial classification of intertidal areas, a portion of the backbarrier tidal flat of Norderney was investigated. Lidar bathymetric data were used for extracting high resolution morphological information. Sidescan sonar mosaics were collected in two following years under contrasting weather conditions. An expert classification based on sidescan sonar backscatter intensity, seafloor texture, morphology, and surface sediment data subdivided the research area into 10 classes. The outcomes were compared with an existing RapidEye-based classification. The tested methods showed both advantages and limitations, which were discussed based on statistical analyses. Satellite and Lidar approaches were most suitable for mapping biogenic features (e.g., shellfish beds) over large areas, whereas sidescan sonar was superior for detail detection and discrimination of morpho-sedimentary regions. As an outlook, it is postulated to perform ground-truthed hydroacoustic mapping on small testing areas, and to use the obtained classification for training satellite-based classification algorithms.

Description: Senckenberg Gesellschaft für Naturforschung (SGN) (3507)

Description: Beaches are characterized by high morphodynamic activity, and high-frequency measurements are needed to understand their states and rates of change. Ideally, beach survey methods should be at once accurate, rapid and low-cost. Recently, unmanned aerial systems (drones) have been increasingly utilized to measure beach topography. In this paper, we present a review of the state of art in drones and photogrammetry for beach surveys and the respective achieved measurement quality (where reported). We then show how drones with a minimal configuration and a low-cost setup can meet the high accuracy and rapidity required for beach surveys. To test a minimal drone and ground control point configuration, we used consumer-grade equipment to perform the same flight path with different cameras and at different altitudes. We then used photogrammetry to produce digital elevation models of the beach. Using a GNSS-RTK system, we collected 2950 independent control points to evaluate the accuracy of the digital elevation models. Results show that, once a few potential sources of uncertainties in the final digital elevation model are taken into account, the average RMSE(z) of the digital elevation models was ~5 cm, with a survey efficiency of ca. 3 m2 min−1. Digital elevation models taken at different times were used to calculate the before–after sediment budget following a storm that hit a sandy coast in Sylt Island at the German North Sea coast.

Description: Leibniz-Zentrum für Marine Tropenforschung (ZMT) GmbH (3494)

Description: The Russian Global Navigation Satellite System (GLONASS) satellites have a stretched body shape and take a specific attitude mode inside the eclipse. Based on previous studies, the new Empirical CODE orbit model (ECOM2) performs better than the classical ECOM model if a satellite has elongated shape or does not maintain yaw-steering mode, and the use of an a priori box-wing (BW) model improves the orbits significantly when employing the ECOM model. However, we find that the ECOM model performs better than the ECOM2 model for GLONASS satellites outside eclipse seasons, while it performs two times worse in eclipse seasons. The use of the conventional box-wing model results in very little improvement. By assessing the ECOM Y〈sub〉0〈/sub〉 estimates, we conclude that there are potential radiators on the -x surface of GLONASS satellites causing orbit perturbations also inside the eclipse. The higher-order Fourier terms of the ECOM2 model can compensate for such effects better than the ECOM model. Based on this finding, we first confirm that GLONASS-K satellites take a similar attitude mode as GLONASS-M satellites inside the eclipse. Then, we adjust optical parameters of GLONASS satellites as part of precise orbit determination (POD) considering the potential radiator and thermal radiation effects. Finally, the adjusted parameters are introduced into a new box-wing model and jointly used with the ECOM and ECOM2 model, respectively. Results show that the amplitude and the dependency of the empirical parameters on the β angle are greatly reduced for both ECOM and ECOM2 models. Rather than the conventional box-wing model, the new box-wing model reduces the orbit misclosure between two consecutive arcs for both GLONASS-M and GLONASS-K satellites. In particular, the improvement in GLONASS-M satellites is more than 30% for the ECOM model during eclipse seasons. Further evaluation from 24-h predicted orbits demonstrates that the improvement during eclipse seasons is mainly in along- and cross-track directions. Finally, we validate GLONASS satellite orbits using Satellite Laser Ranging (SLR) observations. The use of the new box-wing model reduces the spurious pattern of the SLR residuals as a function of β and Δu significantly, and the linear dependency of the SLR residuals on the elongation drops from as large as -0.760 mm/deg to almost zero for both ECOM and ECOM2 models. In general, GLONASS-M satellites benefit more from the new a priori box-wing model and the BW+ECOM model results in the best SLR residuals, with an improvement of about 50% and 20%, respectively, for the mean and standard deviation (STD) values with respect to the orbit products without a priori model.

Description: Technische Universität München (1025)

Description: The precise orbit determination (POD) of Global Navigation Satellite System (GNSS) satellites and low Earth orbiters (LEOs) are usually performed independently. It is a potential way to improve the GNSS orbits by integrating LEOs onboard observations into the processing, especially for the developing GNSS, e.g., Galileo with a sparse sensor station network and Beidou with a regional distributed operating network. In recent years, few studies combined the processing of ground- and space-based GNSS observations. The integrated POD of GPS satellites and seven LEOs, including GRACE-A/B, OSTM/Jason-2, Jason-3 and, Swarm-A/B/C, is discussed in this study. GPS code and phase observations obtained by onboard GPS receivers of LEOs and ground-based receivers of the International GNSS Service (IGS) tracking network are used together in one least-squares adjustment. The POD solutions of the integrated processing with different subsets of LEOs and ground stations are analyzed in detail. The derived GPS satellite orbits are validated by comparing with the official IGS products and internal comparison based on the differences of overlapping orbits and satellite positions at the day-boundary epoch. The differences between the GPS satellite orbits derived based on a 26-station network and the official IGS products decrease from 37.5 to 23.9 mm (34% improvement) in 1D-mean RMS when adding seven LEOs. Both the number of the space-based observations and the LEO orbit geometry affect the GPS satellite orbits derived in the integrated processing. In this study, the latter one is proved to be more critical. By including three LEOs in three different orbital planes, the GPS satellite orbits improve more than from adding seven well-selected additional stations to the network. Experiments with a ten-station and regional network show an improvement of the GPS satellite orbits from about 25 cm to less than five centimeters in 1D-mean RMS after integrating the seven LEOs.

Description: Chinese Government Scholarship http://dx.doi.org/10.13039/501100010890

Description: Inhaltsverzeichnis : EHLERS, J. & MENSCHING, H.: Küstenversatz und Prielverlagerungen an der Nordseeküste. S. 9-22 ; FRÄNZLE, O.: Periglaziäre Formung der Altmoränengebiete Schleswig-Holsteins. S. 23-35 ; HEMPEL, L.: Rezente und fossile Mesoformen der Abtragung und Aufschüttung in Ausräumen von Schichtkammlandschaften im Teutoburger Wald. S. 37-47 ; LEHMEIER, F.: Zum Formenschatz der Schichtkammlandschaft im Niedersächsischen Bergland. S. 49-61 ; GARLEFF, K., BRUNOTTE, E. & STINGL, H.: Fußflächen im zentralen Teil der Hessischen Senke. S. 63-76 ; MÖLLER, K.: Das Eschweger Becken und seine Randbereiche — Ergebnisse geomorphographischer und hydrochemischer Analysen. S. 77-92 ; GLATTHAAR, D.: Vertikalbewegungen und ihre Bedeutung für die Formenentwicklung im Westerwald. S. 93-106 ; MÜLLER, M.J.: Periglaziärfluviale, solifluidale und abluale Formung im westlichen Hunsrück und am Ostrand der Trier-Bitburger Mulde. S. 107-118 ; BARSCH, D. & MÄUSBACHER, R.: Zur fluvialen Dynamik beim Aufbau des Neckarschwemmfächers. S. 119-128 ; LESER, H.: Schichtstufen und Talrandstufen in Südwestdeutschland. S. 129-147 ; FARRENKOPF, D.: Relief und Wasserhaushalt im Eyachtal, Nordschwarzwald. S. 149-154 ; LESER, H. & METZ, B.: Vergletscherungen im Hochschwarzwald. S. 155-175 ; HABBE, K.A.: Was kann eine geomorphologische Vollkartierung für die Stratigraphie des Quartärs leisten? S. 177-196 ; RATHJENS, C.: Jungglaziale Formung und spätglazialer Eisabbau im Chiemgau. S. 197-205 ; FISCHER, K.: Die würmzeitliche und stadiale Vergletscherung der Berchtesgadener Alpen. S. 207-225 ;

Description: research

Description: DFG, SUB Göttingen

Description: Zur Vereinfachung wird die Vielfalt der Karstformenbezeichnungen bereinigt. Erdfall wird als Form, die in nicht verkarstungsfähigen Serien liegt, aber auf Tiefensubrosion zurückgeht, der Doline, einer Form, die in verkarstungsfähigem Material liegt, gegenübergestellt. Als Grundlage der Arbeit wurde eine detaillierte Kartierung der Auslaugungsformen durchgeführt. Hinsichtlich rezenter Subrosion erwies es sich als notwendig, die in Oberflächenwässern und wasserwirtschaftlich erfaßten Wässern gelösten Bestandteile von Chlorid, Sulfat und Karbonat zu ermitteln. Die Auswertung der gewonnenen Daten zeigt, daß ein Zusammenhang mit Gebieten besteht, die durch aktuelle Erdfälle und Dolineneinbrüche gekennzeichnet sind. Als Voraussetzung zur Reliefgenese gilt, daß das Gebiet des Unterwerra-Sattels entscheidend durch die saxonische Gebirgsbildung an der Wende Jura/Kreide und die nachfolgende klimageomorphologische Entwicklung geprägt ist. Anhand der geomorphographischen Analyse wird der Einfluß der Salz-, aber auch der Sulfatauslaugung auf die Landschaftsgenese belegt. Die Auslaugung des Salzes (Nal), dessen Mächtigkeit im Untersuchungsgebiet mit mindestens 120 m angenommen wird, und der unterlagernden ca. 130 m nächtigen Zechsteingipse (A 1 - A 3) zerrüttet die überlagernden triassischen Schichten weiter. Darüber hinaus wirkt die Subrosion von mehr als 30 m Rötgipsen und 50 m Gipsen des Mittleren Muschelkalkes im Hangenden des Zechsteins reliefformend. Die ermittelten Ergebnisse - rezente und subrezente Formen, Lösungswerte – werden zunächst in kleineren Gebietseinheiten analysiert. Die Ergebnisse der Nasseranalysen bestätigen das geomorphographische Ergebnis, so daß in Anlehnung an die Gipshorizonte von Stockwerkssubrosion gesprochen werden kann. Entscheidend geprägt ist die heutige Situation jedoch durch vorangegangene Zechsteinsalzauslaugung im tieferen Untergrund. Diese hat in den Hangendserien die Wasserwegsamkeit verstärkt, so daß die nachfolgende Sulfatsubrosion den Kleinformenschatz vor der Schichtstufe des Mittleren Buntsandsteins steuern konnte. Aufgrund ihrer für Auslaugungsgebiete typischen Ausprägung wird die Lage der Schichtstufe in weiten Teilen des Untersuchungsgebietes an das in Auslaugung befindliche Salz geknüpft. Das Auftreten von Subrosionsformen vor der Landstufe des Kaufunger Waldes, den östlichen Meißnerhängen, dem Anstieg des Schlierbachswaldes sowie vor dem Anstieg des Buntsandsteins zwischen Heldra, Frieda und Bad Sooden-Allendorf untermauert diese Interpretation. In der südlichen und südöstlichen Umrahmung des Untersuchungsgebietes wird der Salzhang aufgrund geomorphographischer Kriterien unter dem Steilanstieg des Unteren Muschelkalkes ausgewiesen. Aufgrund dieser Befunde wird die primäre Salzverbreitung als über den Unterwerra-Sattel reichend angenommen, womit sich, abgesehen von den Einflüssen der saxonischen Tektonik, alle Reliefentwicklungsprozesse allein durch Auslaugung und folgende geomorphologische Überprägung erklären lassen. Darüber hinaus ist dieses Gebiet in Nordhessen nicht nur durch eine über alle Schichten hinweggreifende Rumpfflächenbildung gekennzeichnet, sondern die Resistenzunterschiede wurden - unabhängig vom Klima - beständig herausgearbeitet. Aus diesen Ergebnissen wurde ein übergeordnetes Modell zur Reliefentwicklung erstellt. Danach existieren im Untersuchungsgebiet fünf Reliefgenerationen, wobei die postsaxonische Reliefentwicklung mit zerstörtem, die Auslaugung begünstigendem Hangendverband nach der Landhebung bzw. dem Einbruch der das Gebiet begrenzenden Grabenstrukturen, die bis ins Alttertiär reicht, nicht erfaßt werden konnte. [...]

Description: research

Description: DFG, SUB Göttingen

Description: In der vorliegenden Arbeit wurden Ergebnisse hydrologischer und stratigraphischer Studien zur Entwicklungsgeschichte von Brandenburger Kesselmooren vorgestellt. Für die Erfassung der aktuellen und historischen biotischen und abiotischen Standortfaktoren wurden verschiedene Methoden angewandt: floristische und vegetationskundliche Untersuchungen sowie hydrologische, hydrochemische, geochemische, geophysikalische und sedimentologische Untersuchungen und Makrorest-‚ Mikrorest- und Pollenanalyse. Der zeitlichen Einordnung der entwicklungsgeschichtlichen Prozesse dienten Radiocarbondatierungen und die pollenanalytischen Untersuchungen. Ziel der Arbeit war es, Entwicklungsstadien auszuscheiden, die von den untersuchten Mooren seit ihrer Entstehung durchlaufen wurden. Aufgrund der stratigraphischen Untersuchungen wurden Aussagen zur Beckengenese und zu den einzelnen See- und Moorentwicklungsphasen getroffen, zum Verlandungsvorgang, zu Moorbildungsbedingungen und Sukzessionsstadien. Den Entwicklungsstadien konnten über geochemische und -physikalische Untersuchungen abiotische Standortfaktoren zugeordnet werden. Die aktuellen Standortveränderungen wurden erfaßt und die vorgenommenen Erhaltungs- und Wiedervernässungsmaßnahmen dokumentiert und bewertet.

Description: research

Description: DFG, SUB Göttingen

Description: Dieser Band enthält 63 Artikel zu Themengebieten der Physik der festen Erde, zu magnetischen und elektrischen Feldern der Erde, zu der Physik der Atmophäre und der angewandten Geophysik veröffentlicht durch die Deutsche Geophysikalische Gesellschaft in dem Jahr 1934.

Description: 〈html〉 〈body〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0004.pdf"〉Titelseite〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0005.pdf"〉Autorenverzeichnis〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0006.pdf"〉Sachverzeichnis〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0007.pdf"〉Karl Mack †〈/a〉〈br〉(Hiller, W.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0008.pdf"〉Die südalbanischen Erdbeben 1930/31〈/a〉〈br〉(Nowack, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0009.pdf"〉Seismische Untersuchungen des Geophysikalischen Instituts in Göttingen〈/a〉〈br〉(Gräfe, H., v. zur Mühlen, W., Müller, H. K.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0017.pdf"〉Horizontalsicht bei örtlich veränderlicher Trübung und Beleuchtung〈/a〉〈br〉(Steinhäusser, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0018.pdf"〉Referate und Mitteilungen〈/a〉〈br〉(Haase, H., Köhler, R., Berroth, A.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0019.pdf"〉Beitrag zur Berechnung von Minimum-Stabpendeln〈/a〉〈br〉(Graf, A.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0020.pdf"〉Zur Theorie elastischer Pendel mit besonderer Berücksichtigung des Holweck-Lejayschen Stabpendels〈/a〉〈br〉(Graf, A.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0021.pdf"〉Eine neue Methode für sehr präzise magnetische Messungen〈/a〉〈br〉(Koulomzine, T., Bondaletoff, N.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0022.pdf"〉Zur Frage der mit dem temperaturkompensierten Magnetsystem erreichbaren Meßgenauigkeit〈/a〉〈br〉(Kohl, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0023.pdf"〉Die Höhenverteilung der Erd-, Luft- und Höhenstrahlung〈/a〉〈br〉(Suckstorff, G. A.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0024.pdf"〉Erdstrahlungsmessungen in Bad Nauheim nach der Gammastrahlenmethode〈/a〉〈br〉(Masuch, V.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0025.pdf"〉Referate〈/a〉〈br〉(Jung, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0026.pdf"〉Abschnitt〈/a〉〈br〉(Angenheister, G., Kohlschütter, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0027.pdf"〉Hergesell geb. 29. Mai 1859〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0028.pdf"〉Hecker geb. 21. Mai 1864〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0029.pdf"〉Sprengungen zur Forschungszwecken mit Unterstützung der Notgemeinschaft der Deutschen〈/a〉〈br〉(Duckert, P.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0037.pdf"〉Beiträge zu den Luftschallmessungen〈/a〉〈br〉(Meißer, O., Martin, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0039.pdf"〉Seismische Untersuchungen des Geophysikalischen Instituts in Göttingen〈/a〉〈br〉(Regula, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0042.pdf"〉Berechnung der Laufzeitkurven des anormalen Schalles für windstille Atmosphäre und Vergleich mit der Laufzeitkurve der Oldebroek-Sprengung vom 15. Dezember 1932〈/a〉〈br〉(Jung, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0043.pdf"〉Ergebisse der Registrierungen von Schallwellen an kreisförmig um den Sprengherd angeordneten Stationen〈/a〉〈br〉(Duckert, P.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0044.pdf"〉Beobachtungsergebnisse über den Einfluß der "akustischen Umkehrschicht" auf die Schallausbreitung〈/a〉〈br〉(Sandmann, B.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0045.pdf"〉Zur Frage der anomalen Schallausbreitung〈/a〉〈br〉(Kölzer, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0046.pdf"〉Schalluntersuchungen im Polargebiet〈/a〉〈br〉(Wölcken, K.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0049.pdf"〉Betrachtungen über ebene Pendel〈/a〉〈br〉(Hahnkamm, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0051.pdf"〉Außenraum und Innenraum (Schlichtung des Streites um die Schwerkraftreduktion)〈/a〉〈br〉(Schwinner, R.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0052.pdf"〉Bemerkungen zu den Geoiden von Ackerl und Hirvonen〈/a〉〈br〉(Ledersteger, K.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0053.pdf"〉Auto-Radio als Hilfsmittel geologischer Kartierung〈/a〉〈br〉(Cloos, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0054.pdf"〉Zur photographischen Registrierung von Stationsseismometern〈/a〉〈br〉(Meißer, O.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0056.pdf"〉Ein Horizontalseismometer für die Aufzeichnung von starken Orts- und Nahbeben〈/a〉〈br〉(Critikos, N. A.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0059.pdf"〉Die Bedeutung der Unstetigkeiten im Verlauf der Schallgeschwindigkeit mit der Höhe für die normale und anomale〈/a〉〈br〉(Sandmann, B.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0060.pdf"〉Referate und Mitteilungen〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0061.pdf"〉Die Relativität der Undulationen〈/a〉〈br〉(Hopfner, F.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0062.pdf"〉Ein detonierendes Meteor über dem Weserbergland am 2. Januar 1934〈/a〉〈br〉(Hartmann, W.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0063.pdf"〉Der Meteorfall bei Stadt Rehburg am 2. Januar 1934〈/a〉〈br〉(Trommsdorff, W.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0064.pdf"〉Vergleich zwischen der Intensität der kosmischen Ultrastrahlung über Grönland und über Deutschland〈/a〉〈br〉(Wölcken, K.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0065.pdf"〉Das Grundeis〈/a〉〈br〉(Jakuschoff, P.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0066.pdf"〉Le problème des microséismes et le déferlement des vagues〈/a〉〈br〉(Gherzi, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0067.pdf"〉Note on the Hayford-Bowie tables for calculation 〈i〉g〈/i〉〈/a〉〈br〉(Bullard, E. C.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0068.pdf"〉Kann die Laplacesche Differentialgleichung für das Schwerkraftpotential auch innerhalb der Erdkruste als erfüllt angesehen werden?〈/a〉〈br〉(Grabowski, L.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0069.pdf"〉Vorträge, gehalten auf der XI. Tagung der Deutschen Geophysikalischen Gesellschaft, am 13. bis 15. September 1934 in Pyrmont〈/a〉〈br〉(Jung, K.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0072.pdf"〉Der geophysikalische Nachweis des Zechsteindolomits〈/a〉〈br〉(Müller, M.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0073.pdf"〉Berichtigung〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0074.pdf"〉Vorträge, gehalten auf der XI. Tagung der Deutschen Geophysikalischen Gesellschaft, am 13. bis 15. September 1934 in Pyrmont〈/a〉〈br〉(von Seidlitz, W., Sieberg, A., Linke, F., Gerlach, W.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0079.pdf"〉Zur Frage der Geländekorrektion bei Drehwaagemessungen〈/a〉〈br〉(Tuchel, G.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0080.pdf"〉Emanation in Boden- und Freiluft〈/a〉〈br〉(Israël, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0081.pdf"〉Die Energie der Heliokathodenstrahlen in ihrer Beziehung zur fortschreitenden Bewegung der Elektronen in den Polarlichtstrahlen〈/a〉〈br〉(Rudolph, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0082.pdf"〉Weitere Untersuchungen mit dem Sanford-Elektrometer〈/a〉〈br〉(Stoppel, R.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0083.pdf"〉Das Strömungssystem der Luft über Mogadischu〈/a〉〈br〉(Bossolasco, M.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0084.pdf"〉Messungen mit transportablen statischen Schweremessern〈/a〉〈br〉(Schleusener, A.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0086.pdf"〉Über den Energietransport bei der Sprengseismik〈/a〉〈br〉(v. Schmidt, O.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0087.pdf"〉Formen der Bodenschwingung bei sinusförmiger Anregung〈/a〉〈br〉(Köhler, R.)〈/li〉 〈li〉〈a href=" https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0088.pdf"〉Die Ausbreitungsgeschwindigkeit sinusförmiger elastischer Wellen im Boden〈/a〉〈br〉(Ramspeck, A.)〈/li〉 〈li〉〈a href=" https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0089.pdf"〉Referate und Mitteilungen〈/a〉〈br〉(Haase, H.)〈/li〉 〈li〉〈a href=" https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0090.pdf"〉Bericht über die elfte Tagung der Deutschen Geophysikalischen Gesellschaft vom 13. bis 15. September 1934 in Bad Pyrmont〈/a〉〈br〉(Jung, K.)〈/li〉 〈li〉〈a href=" https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0091.pdf"〉Berichtigung〈/a〉〈/li〉 〈li〉〈a href=" https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0092.pdf"〉Geophysikalische Berichte〈/a〉〈/li〉 〈li〉〈a href=" https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0093.pdf.pdf"〉Register der Geophysikalischen Berichte〈/a〉〈/li〉 〈li〉〈a href=" https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0010/LOG_0094.pdf"〉Mitgliederverzeichnis der Deutschen Geophysikalischen Gesellschaft nach dem Stande vom 1. Dezember 1934〈/a〉〈/li〉 〈/body〉 〈/html〉

Description: research

Description: DGG, DFG, SUB Göttingen

Description: Deutschlands Erdbebentätigkeit pflegt unterschätzt zu werden, weil sie gewöhnlich so harmlos erscheint. Zwar bringt der Jahresverlauf nur wenige Beben, abgesehen von gelegentlichen Schwärmen mit vielen hunderten von Einzelstößen, wie sie besonders dem Vogtland eigentümlich sind. Zudem handelt es sich dabei vorwiegend um schadlose Erderschütterungen, die kaum Beobachtung finden. Aber der Fachmann kennt daneben auch bis in die neueste Zeit hinein Erdbeben mit erheblichen Schäden und selbst Zerstörungen, die für längere Zeit das öffentliche Leben völlig beherrscht haben; mitunter wurde fast Großbebencharakter erreicht.

Description: research

Description: DFG, SUB Göttingen

Description: Die nachstehenden neueren Untersuchungen auf verschiedenen Gebieten geophysikalischer Forschung, die von Mitgliedern der Reichsanstalt für Erdbebenforschung in Jena durchgeführt sind, wurden erstmalig in der Festschrift zum 70. Geburtstage des früheren Direktors der Reichsanstalt, Herrn Geheimrat Professor Dr. Oskar Hecker (Beitrage zur Angewandten Geophysik, Band 4, Heft 3, Leipzig 1934) veröffentlicht. Sämtliche Arbeiten, ausgenommen diejenigen von Krumbach, gehören zu den von der Notgemeinschaft der Deutschen Wissenschaft unterstützten geophysikalischen Forschungen. A. Sieberg

Description: research

Description: DFG, SUB Göttingen

Description: Am Beispiel des "Leegmoores" im Timpemoor - einem ehemaligen "Heidemoor" - wurde auf Grund von boden- und moorkundlichen Untersuchungen sowie von landeskundlich-historischen Recherchen die Entwicklung der Heidemoore überprüft. Dazu wurden erstmalig die flächenhaften Verluste an Moorsubstanz durch - wiederholte Moorbrandkultur, - Entnahme von Heidesoden (Abplaggen) und - Winderosion qualitativ und quantitativ erfaßt, dazu die Moorsackung errechnet. Aus den vorhandenen moorkundlichen Fakten konnte das natürliche Moorrelief des Timpemoores rekonstruiert werden. Die Autoren weisen nach, daß die von JONAS (1934, 1935) beschriebenen Heidemoore "durch den Menschen beeinflußte Moore" darstellen. Das untersuchte Timpemoor hat sich danach im Verlauf mehrerer Jahrhunderte aus einem natürlichen gewölbten Hochmoor gebildet.

Description: On the basis of pedological, peatland and historical investigations the origin of raised bogs with heather vegetation ("Heidemoore")was examined at the example "Leegmoor", a part of the "Timpemoor". In addition to that for the first time the loss of peat substance by - burnt-over peatland cultivation, - cutaway heather sods, - erosion by wind and - bog subsidence was calculated. With the available peatland facts it was possible to reconstruct the natural bog relief. The authors are able to demonstrate that the "Heidemoore" described by JONAS (1934, 1935) are bogs influenced by man. During the last centuries the Timpemoor developed from a natural raised bog (with convex centre) to a raised bog with heather vegetation.

Description: research

Description: DFG, SUB Göttingen

Description: Vergleichende Darstellung und Analyse der Arbeitsvorgänge in den Agrarlandschaften der Erde. Dieser Aufgabe unterzieht sich in einem ersten Schritt die vorliegende Studie. Sie strebt an, mit der Darstellung und Analyse des jährlichen Arbeitsvorganges die bisher wenig berücksichtigte dynamische Seite der Agrarlandschaft – ihre Rhythmik nämlich – in exakter Weise erfassen zu können. Im Vordergrund steht zunächst weniger die regionale als vielmehr die sachliche Erörterung, auf der Beispielsgrundlage jedoch einer regionalen Kontrastierung innerhalb Deutschlands bzw. aus naheliegenden Gründen der Bundesrepublik Deutschland. Späteren großräumigen Untersuchungen erst kann es vorbehalten sein, von der hier geschaffenen Plattform aus auf eine speziell regionale Betrachtungsweise überzugehen.

Description: research

Description: DFG, SUB Göttingen

Description: An der Hand von Erdbeben, die im Boden Deutschlands entstanden sind, sollen folgende Fragen untersucht werden: 1) Die Wirkungsweise der einzelnen Bebenherde, von denen anzunehmen ist, dass sie verschiedenartige Charaktereigenschaften haben. Hierfür ist es notwendig, festzustellen einmal Lage und geometrisches Bild des Herdes als geologische Störungsstelle, andererseits den das Erdbeben auslösenden Bewegungsvorgang in der Herdstörung. 2) Die Abhängigkeit der scheinbaren Bebenstarken innerhalb des Schüttergebietes von Bodenbeschaffenheit und Tektonik.

Description: research

Description: DFG, SUB Göttingen

Description: Dieser Band enthält 77 Beiträge zu Themengebieten der Physik der festen Erde, des magnetischen und elektrischen Felds der Erde, der Physik der Atmosphäre sowie der Angewandten Geophysik, veröffentlicht durch die Deutsche Geophysikalische Gesellschaft in den Jahren 1930.

Description: 〈html〉 〈body〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0004.pdf"〉Titelseite〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0005.pdf"〉Ein neuer Vierpendelapparat für relative Schweremessungen〈/a〉〈br〉(Meisser, O.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0007.pdf"〉Geophysikalische Messungen unter Tage〈/a〉〈br〉(Meisser, O., Wolf, F.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0008.pdf"〉Die ersten Dickenmessungen des grönländischen Inlandeises〈/a〉〈br〉(Sorge, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0010.pdf"〉Die seismische Bodenunruhe in Hamburg und ihr Zusammenhang mit der Brandung〈/a〉〈br〉(Mendel, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0012.pdf"〉Die sonnenbelichteten Nordlichtstrahlen und die Konstitution der höheren Atmosphärenschichten〈/a〉〈br〉(Vegard, L.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0013.pdf"〉Nochmals: Zur Frage der Laufzeitkurven〈/a〉〈br〉(Gutenberg, B.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0014.pdf"〉Erwiderung zur vorstehenden Arbeit von Herrn Prof. Gutenberg〈/a〉〈br〉(Krumbach, G.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0015.pdf"〉Bemerkungen zu der vorstehenden Erwiderung〈/a〉〈br〉(Gutenberg, B.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0016.pdf"〉Einfluß des Mondes auf die erdmagnetischen Elemente in Samoa〈/a〉〈br〉(Fanselau, G.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0017.pdf"〉Ein Diagramm zur Bestimmung der Differenz der Schwerestörung 〈i〉Δg〈/i〉 in zwei Beobachtungspunkten〈/a〉〈br〉(Oserezky, W.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0018.pdf"〉Zur Ermittlung ausgedehnter Schichten verschiedener Leitfähigkeit〈/a〉〈br〉(Koenigsberger, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0019.pdf"〉Über tägliche erdmagnetische Variationen in zwei Alpentälern〈/a〉〈br〉(Koenigsberger, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0020.pdf"〉Die Wirkung der obersten Erdschicht auf die Anfangsbewegung einer Erdbebenwelle〈/a〉〈br〉(Hasegawa, M.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0021.pdf"〉Über die Elastizität von Gesteinen〈/a〉〈br〉(Breyer, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0023.pdf"〉Über den Horizontalabstand von Pendelstationen〈/a〉〈br〉(Schwinner, R.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0024.pdf"〉Die Belowsche Methode zur Bestimmung der Wirkung gegebener Massen auf Krümmungsgröße und Gradient, ihre Verallgemeinerung für beliebige Massenformen und ihre Anwendung auf "zweidimensionale" Massenanordnungen〈/a〉〈br〉(Jung, K.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0028.pdf"〉Harmonische Schwingungen des Untergrundes〈/a〉〈br〉(Köhler, R.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0029.pdf"〉Mitteilungen〈/a〉〈br〉(Fleming, I. A., Linke, F.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0030.pdf"〉Über die Ursache der erdmagnetischen Störung im Gebiet der Freien Stadt Danzig〈/a〉〈br〉(Haalck, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0031.pdf"〉Die kontinentalen Verschiebungen von Amerika und Madagaskar〈/a〉〈br〉(Livländer, R.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0032.pdf"〉Magnetische Vermessung einiger tertiärer Eruptivgänge und -stöcke im sächsischen Elbsandsteingebirge〈/a〉〈br〉(Schulze, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0033.pdf"〉Über die Existenz einer mondentägigen Variation in den Erdströmen〈/a〉〈br〉(Egedal, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0034.pdf"〉Zum Trübungsfaktor〈/a〉〈br〉(Feussner, K., Friedrichs, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0035.pdf"〉Temperature changes between Torsion balance readings in the State of Texas〈/a〉〈br〉(Harris, S.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0036.pdf"〉Über isostatische Schwereanomalien und deren Beziehung zu den totalen Anomalien〈/a〉〈br〉(Jung, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0037.pdf"〉Bemerkungen zu den Ausführungen von H. Jung〈/a〉〈br〉(Ansel, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0038.pdf"〉Mitteilungen〈/a〉〈br〉(Linke, F.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0040.pdf"〉Wesensgleiche und wesensverschiedene Darstellungen〈/a〉〈br〉(Nippoldt, A.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0041.pdf"〉Die Säkularvariation in der Rheinpfalz in den Jahren 1850 bis 1928〈/a〉〈br〉(Burmeister, F.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0042.pdf"〉Größenverhältnis von remanentem zu induziertem Magnetismus in Gesteinen; Größe und Richtung des remanenten Magnetismus〈/a〉〈br〉(Koenigsberger, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0043.pdf"〉Über eine magnetische Anomalie am Lebasee in Ostpommern〈/a〉〈br〉(Reich, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0045.pdf"〉Die Ergebnisse der magnetischen Messungen in der Ostsee in den Jahren 1924 bis 1929〈/a〉〈br〉(v. Gernet-Reval, A.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0047.pdf"〉Erdmagnetische Messungen in Bulgarien, Mazedonien, Trazien und in der Dobrudja〈/a〉〈br〉(Popoff, K.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0048.pdf"〉Einige Bemerkungen über erdmagnetische Messungen, welche in Feodossia ausgeführt wurden〈/a〉〈br〉(Palazzo, L.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0049.pdf"〉Possible causes of abnormal polarizations of magnetic formations〈/a〉〈br〉(Heiland, C.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0050.pdf"〉Die geologische Bedeutung der Schaffung einer Isanomalenkarte der magnetischen Vertikalintensität von Deutschland〈/a〉〈br〉(Schuh, F.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0051.pdf"〉Die innere Genauigkeit von Inklinationsmessungen mit dem Erdinduktor〈/a〉〈br〉(Venske, O.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0052.pdf"〉Theorie einer neuen galvanischen Waage〈/a〉〈br〉(Bock, R.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0053.pdf"〉Messungen im Luftschiff〈/a〉〈br〉(Haussmann, K.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0054.pdf"〉Une modification de l'enregistreur à marche rapide et à petite consommation de papier de Ad. Schmidt pour l'application aux stations de l'Anneé Polaire 1932–1933〈/a〉〈br〉(la Cour, D.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0056.pdf"〉Was sagen uns die Parameter eines Magneten?〈/a〉〈br〉(Fanselau, G.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0057.pdf"〉Über die Herleitung des Potentials des täglichen erdmagnetischen Variationsfeldes〈/a〉〈br〉(Egedal, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0058.pdf"〉Über den Vektor der magnetischen Störungen im aperiodischen Verlauf〈/a〉〈br〉(Keränen, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0059.pdf"〉Forschungsmethode über den Zusammenhang zwischen der Sonnenfleckentätigkeit und den erdmagnetischen Störungen〈/a〉〈br〉(Gehlinsch, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0060.pdf"〉Der Temperaturverlauf im Sandboden〈/a〉〈br〉(Süring, R.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0061.pdf"〉Die dominierende Luftdruckwelle des strengen Winters 1928/29〈/a〉〈br〉(Weickmann, L.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0063.pdf"〉Über einige meteorologische Begriffe〈/a〉〈br〉(Tetens, O.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0066.pdf"〉Über die Feinstruktur des Temperaturgradienten längs Berghängen〈/a〉〈br〉(Wagner, A.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0067.pdf"〉Das unperiodische Element im Tropenklima〈/a〉〈br〉(Knoch, K.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0068.pdf"〉Zur Theorie der Maxwellschen Geschwindigkeitsverteilung in turbulenten Strömungen〈/a〉〈br〉(Ertel, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0069.pdf"〉Wie tief dringen die Polarlichter in die Erdatmosphäre ein?〈/a〉〈br〉(Störmer, C.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0072.pdf"〉Gammastrahlen an Kaliumsalzen〈/a〉〈br〉(Kolhörster, W.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0073.pdf"〉Über die Form der Fernschallwelle〈/a〉〈br〉(Kühl, W.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0074.pdf"〉Die Seismizität des Südantillenbogens〈/a〉〈br〉(Tams, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0076.pdf"〉Eine neue württembergische Erdbebenwarte〈/a〉〈br〉(Kleinschmidt, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0077.pdf"〉Über den Zusammenhang zwischen Typhusmorbidität (bzw. Typhusmortalität) und Niederschlagsschwankungen nebst einer Kritik der Brücknerschen Klimaperiode〈/a〉〈br〉(Wenzel Pollak, L.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0079.pdf"〉Über die Abhängikeit der Schwerkraft vom Zwischenmedium〈/a〉〈br〉(Schlomka, T.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0080.pdf"〉On the Determination of the Lunar Atmospheric Tide〈/a〉〈br〉(Chapman, S.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0081.pdf"〉Die Wärmeumsatz durch die Wärmestrahlung des Wasserdampfes in der Atmosphäre〈/a〉〈br〉(Albrecht, F.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0082.pdf"〉Ein Universal-Induktionsmagnetometer〈/a〉〈br〉(Uljanin, W.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0083.pdf"〉Der große Staubfall vom 26. bis 29. April 1928 in Südosteuropa〈/a〉〈br〉(Stenz, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0085.pdf"〉Ein neues Verfahren der luftelektrischen Raumladungsmessung〈/a〉〈br〉(Wigand, A., Schubert, J., Frankenberger, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0086.pdf"〉Kurze Erwiderung auf Vegards Bemerkungen über sonnenbelichtete Nordlichtstrahlen〈/a〉〈br〉(Störmer, C.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0088.pdf"〉Die Invariabilität und Abstimmung von Minimumpendeln〈/a〉〈br〉(Kohlschütter, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0089.pdf"〉Bemerkung zu der Arbeit "Die Invariabilität und Abstimmung von Minimumpendeln" von E. Kohlschütter〈/a〉〈br〉(Meisser, O.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0090.pdf"〉Erwiderung〈/a〉〈br〉(Kohlschütter, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0091.pdf"〉Bemerkungen zu der Arbeit von Herrn Dr. O. Meisser: "Ein neuer Vierpendelapparat für relative Schweremessungen"〈/a〉〈br〉(Heiland, C.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0092.pdf"〉Bemerkungen zu den vorstehenden Ausführungen von Herrn Prof. Dr. C. A. Heiland〈/a〉〈br〉(Meisser, O.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0093.pdf"〉Das Epizentrum des südatlantischen Großbebens vom 27. Juni 1929〈/a〉〈br〉(Tams, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0094.pdf"〉Seismische Untersuchungen auf dem Pasterzegletscher. I〈/a〉〈br〉(Brockamp, B., Mothes, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0096.pdf"〉Bericht über die neunte Tagung der Deutschen Geophysikalischen Gesellschaft vom 11. bis 14. September 1930 in Potsdam〈/a〉〈br〉(Mügge, Linke, F.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0097.pdf"〉Autorenverzeichnis〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0098.pdf"〉Sachverzeichnis〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0099.pdf"〉Literaturverzeichnis〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0100.pdf"〉Geophysikalische Berichte〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0101.pdf"〉Register der Geophysikalischen Berichte〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0006/LOG_0102.pdf"〉Mitgliederverzeichnis der Deutschen Geophysikalischen Gesellschaft nach dem Stande vom 1. Oktober 1930〈/a〉〈/li〉 〈/body〉 〈/html〉

Description: research

Description: DGG, DFG, SUB Göttingen

Description: Abstract: Current information on the potential distribution and condition of peatland soils are of great importance. This applies notably for actions with respect to climate and environmental protection. The Ministry of infrastructure and agriculture in the federal state of Brandenburg (MIL) therefore initiated a project to provide a complete and updated map of peatland soils for the federal state of Brandenburg, Germany, for the year 2013. Extensive legacy data on both, areal extent of peatland soils as well as soil profile information where made digitally available in a homogeneous map and a consistent database. Approximately 7.725 sites were randomly selected from legacy soil data and currently reinvestigated to draw inference on the current condition of peatland soils. Statistically derived peatland subsidence rates at grassland sites of 0.50 cm/yr and 0.57 cm/yr at arable sites fit well with published values in comparable regions of central Europe. Our results prove the great dynamics of soil development on agriculturally used peatlands. Concerning Brandenburg, the area of peatland soils decreased from 270.000 ha in the early 20th century (Prussian geological map) to actually 163.000 ha.

Description: Zusammenfassung: Aktuelle Informationen zur Verbreitung und zum Zustand der Moorböden sind vor dem Hintergrund der geplanten Einführung von Agrarumwelt- und Klimamaßnahmen in der Landwirtschaft von besonderer Bedeutung. Das Ministerium für Infrastruktur und Landwirtschaft des Landes Brandenburg (MIL) hat hierzu das Projekt „Schaffung einer Datengrundlage für die Ableitung von Agrarumwelt- und Klimamaßnahmen auf Moorstandorten in Brandenburg“ initiiert. Mit dem Ziel der Bereitstellung einer auf das Jahr 2013 bezogenen Moorkarte wurden umfangreiche, bis dato nicht genutzte Datenbestände zur Verbreitung von Moorböden in Brandenburg zu einer überschneidungsfreien Karte und umfassenden Datenbank moorbodenkundlicher Bodenprofile verarbeitet. Um den aktuellen Zustand der Moorböden zu erfassen, wurden flächenrepräsentativ und zufällig an 7.725 Standorten mit ausreichender Datenbasis erneut bodenkundliche Erhebungen durchgeführt und statistisch ausgewertet. Im Ergebnis konnten Mächtigkeitsverlustraten für landwirtschaftlich genutzte Moorstandorte in Brandenburg abgeleitet werden. Für flachgründige Niedermoorstandorte unter Grünland liegen sie bei 0,50 cm/a, vergleichbare ackerbaulich genutzte Standorte liegen mit 0,57 cm/a darüber. Dies deckt sich gut mit publizierten Werten an vergleichbaren Standorten in Zentraleuropa. Die Fläche der Moorböden in Brandenburg hat sich von Anfang des 20. Jahrhunderts von 270.000 ha, ausgewiesen auf Basis der Preußisch geologisch-agronomische Karte (PGK), auf heute noch 163.000 ha reduziert.

Description: DFG, SUB Göttingen, DGMT

Description: research

Description: Abstract: Peatlands are intensively exchanging greenhouse gases with the free atmosphere. Natural peatlands, mires, sequester carbon dioxide as carbon in the peat and emit methane. Peatlands under agriculture or forest are mostly drained and emit carbon dioxide due to peat mineralization and nitrous oxide due to fertilization and nitrogen mineralization. In order to characterize the actual situation and to evaluate measures for the reduction of greenhouse gas emissions measured values on gas exchange are needed. Within two national projects direct measurements of the greenhouse gas exchange have been conducted on a wide range of sites, covering different peatland types, land use forms and hydrological situations and using a standardized methodology. Between 2007 and 2012 22 sites have been studied in Lower Saxony over at least two years using the closed cover method. An overview on sites and results is given. Moreover, approaches to estimate the greenhouse gas emissions due to peat excavation and horticultural peat use are presented. Own emission factors and data from literature are used to estimate the contribution of peatlands and peat use to the greenhouse gas emissions of Lower Saxony. Finally measures for the reduction of greenhouse gas emissions are discussed and estimates on reduction costs are given from examples.

Description: Zusammenfassung: Moore stehen in einem intensiven Gasaustausch mit der Atmosphäre. Natürliche Moore haben über Jahrtausende Kohlendioxid aufgenommen und den Kohlenstoff als Torf gespeichert. Dabei haben sie Methan abgegeben. Entwässerte und genutzte Moore setzen den Kohlenstoff als Kohlendioxid wieder frei und emittieren zudem klimarelevantes Lachgas als Ergebnis der Stickstoffdüngung und der Torfmineralisation. Zur Charakterisierung der Ist-Situation und zur Beurteilung von Maßnahmen ist es erforderlich, belastbare Daten über die Treibhausgasemissionen der Moore zu haben. Im Rahmen von zwei bundesweit angelegten Verbundvorhaben wurden an einer Vielzahl von Standorten unterschiedlichen Moortyps, unterschiedlicher Nutzung und unterschiedlicher Klima- und Wasserregime mit einer abgestimmten Methodik die Flüsse der wesentlichen Treibhausgase direkt gemessen. Im Rahmen dieser Verbundvorhaben wurden in Niedersachsen zwischen 2007 und 2012 an 22 Standorten mindestens zweijährige Messungen mit der Haubentechnik vorgenommen. Dieser Beitrag gibt einen Überblick über untersuchte Standorte und Messergebnisse. Darüber hinaus werden Ansätze zur Ermittlung der Treibhausgasemissionen aus der industriellen Torfgewinnung dargestellt. Unter Verwendung eigener Ergebnisse und von Literaturdaten wird eine Abschätzung der Treibhausgasemissionen aus Moor und Torfgewinnung für das Land Niedersachsen vorgenommen. Abschließend geht der Beitrag auf Maßnahmen zur Verminderung der Treibhausgasemissionen aus Mooren sowie beispielhaft auf Emissionsminderungskosten ein.

Description: DFG, SUB Göttingen, DGMT

Description: research

Description: STÄBLEIN, G.: Regionale Geomorphologie ; KERTESZ, A.: Geomorphologische Kartierung in der Bundesrepublik Deutschland und in Ungarn. Ein Vergleich der Methodik ; BOLLMANN, I.: Geomorphologische Daten und kartographische Darstellung ; PACHUR, H.-J. & RÖPER, H.-P.: Geolimnologische Befunde des Berliner Raumes ; REMMELE, G.: Holozäne Morphodynamik an Schichtstufenhängen — Untersuchungen in Nordwest-Irland ; MÜLLER, MJ. & STRASSER, R.: Holozäne Geomorphodynamik und Landschaftsentwicklung am Ostrand der Trier-Luxemburger Mulde ; KLEBER, A.: Zur jungtertiären Reliefentwicklung im Vorland der südlichen Frankenalb ; HAMANN, C.: Windwurf als Ursache der Bodenbuckelung am Südrand des Tennengebirges, ein Beitrag zur Genese der Buckelwiesen ; ZÖLLER, L.: Neotektonik am Hunsrückrand ; SEPPÄLÄ, M.: Glazialhydrologie des Inlandeises, eine geomorphologische Interpretation der Verhältnisse in Finnland ; JÄKEL, D.: Untersuchungen und Analysen zur Entstehung der Hamada ; GARLEFF, K. & STINGL, H.: Neue Befunde zur jungquartären Vergletscherung in Cuyo und Patagonien ; STINGL, H. & GARLBFF, K.: Tertiäre und pleistozäne Reliefentwicklung an der interozeanischen Wasserscheide in Südpatagonien (Gebiet von Rio Turbio, Argentinien) ; SCHMIDT, K.H.: Nachweis junger Krustenbewegungen auf dem Colorado Plateau, USA ; KUHLE, M.: Zur Geomorphologie Tibets, Bortensander als Kennformen semiarider Vorlandvergletscherung . ; STÄBLEIN, G.: Deutscher Arbeitskreis für Geomorphologie ;

Description: research

Description: DFG, SUB Göttingen, FU Berlin

Description: Abstract: In addition to the widespread use of peatlands for agricultural purposes, which is also common in other German states, the raised bogs in Lower Saxony are still also used up to the present day for housing, as well as for industrial peat extraction. The Peatland Conservation Programme in Lower Saxony launched in 1981 therefore only covered raised bogs to disentangle the different uses, and to systematise the nature protection activities in raised bogs. The priority areas for the extraction of peat defined in the Federal State Regional Planning Programme are to be rescinded. The new State Development Programme being formulated will not only include the nature conservation of peatlands, but also for the first time, deal with the climate protection afforded by these very important storage areas for carbon. An important aspect in this regard is the incorporation of fens, and the discharge from peatlands into underlying water bodies. The database and the conclusions which contribute to the implementation of climate protection in peatland conservation programmes, will be discussed and compared with the peatland conservation previously implemented pursuant to the Peatland Conservation Programme in Lower Saxony. An overview describes various approaches for peatland and climate protection implemented by private initiatives, nature conservation societies, EU-Life-Projects, contractual nature protection, publicly owned businesses and authorities in Lower Saxony, research projects on alternative uses, and climate certificate trading. These varied instruments are compared to highlight their relative areal effectiveness, and relevance, followed by an estimate of the potential for future peatland and climate protection in Lower Saxony.

Description: Zusammenfassung: Neben der auch in anderen Bundesländern weit verbreiteten landwirtschaftlichen Nutzung von Mooren werden die niedersächsischen Hochmoore bis heute auch als Siedlungsraum und zur industriellen Torfgewinnung genutzt. Daher umfasste das niedersächsische Moorschutzprogramm von 1981 nur die Hochmoore, um diese verschiedenen Nutzungen zu entflechten und den Naturschutz in Hochmooren zu systematisieren. Die bisher im Landesraumordnungsprogramm ausgewiesenen Vorranggebiete für die Rohstoffgewinnung von Torf sollen gestrichen werden. In ein neu aufzustellendes Landesentwicklungsprogramm soll neben dem Naturschutz von Mooren erstmalig auch der Klimaschutz dieser wichtigen Kohlenstoffspeicher eingehen. Von besonderer Bedeutung sind hierbei die Einbeziehung der Niedermoore und der Stoffaustrag aus Mooren in unterliegende Gewässer. Die Datengrundlagen und Schlussfolgerungen, die zur Implementierung des Klimaschutzes in den Moorschutz beitragen, werden diskutiert und mit dem bisher umgesetzten Moorschutz nach dem niedersächsischen Moorschutzprogramm verglichen. Ein Überblick beschreibt verschiedene Ansätze zum Moor- und Klimaschutz von Privatinitiativen, von Naturschutzverbänden, mit EU-Life-Projekten, im Vertragsnaturschutz, von niedersächsischen Landesbetrieben und Behörden, von Forschungsprojekten zu alternativen Nutzungen und beim Handel mit Klima-Zertifikaten. Diese unterschiedlichen Instrumente werden in ihrer Flächenwirksamkeit und Relevanz in Beziehung gesetzt und das Potenzial für den künftigen Moor- und Klimaschutz in Niedersachsen abgeschätzt.

Description: DFG, SUB Göttingen, DGMT

Description: research

Description: Simulationen mithilfe des Models 4C zu möglichen Auswirkungen der Klimaänderungen des RCP 8.5 Klimaszenariums auf Wälder in Deutschland Kiefer Fichte Eiche Buche KATASTER-BESCHREIBUNG: Auswirkungen des Klimawandels (Temperatur, Niederschlag, CO2-Gehalt der Atmosphäre) auf die Wälder KATASTER-DETAIL: Delta T (Frühjahr) + und Delta Nied (Frühjahr) -, dann Produktivität der Wälder -; Delta C02 + um 25 - 30 %, dann Produktion der Wälder + um 9 - 20%; Delta T + (an nicht wasserlimitierten Standorten), dann Produktivität der Wälder +; Delta CO2+, dann Wassernutzungseffizienz der Wälder +; Delta T (Sommer) +, dann Waldbrandgefahr +; Delta T (Sommer) + und Delta Nied (Sommer) - (= WaBi -), dann Trockenstress der Wälder + um bis zu 9% und dann Produktivität der Wälder -; Delta T (Sommer) + und Delta Nied (Sommer) -, dann Populationsdichte Kiefern-Großschädlinge +;

Description: Übersicht über bisherige, dokumentiere Zusammenhänge einer Klimaänderung und pilzliche Krankheiten in Raps, Abschätzungen über das Auftreten von Verticillium longisporum, Sclerotinia sclerotiorum, Alternaria brassicae und Phoma lingam an Raps in der Zukunft KATASTER-BESCHREIBUNG: Projektionen über das Auftreten von pilzlichen Pathogenen in Raps, Basiszeitraum 1971-2000, Szenario A1B, REMO, 2001-2030 und 2071-2100, Zusammenhang zwischen Grad-Tagen(〉0°C), Pflanzenentwicklung und Krankheitsparametern als Regressionsfunktionen im Artikel, jedoch sind feiner aufgelöste Projektion von RCM als Tageswerte erforderlich, um Wachstumszyklen zu simulieren und genauere Aussagen zu erhalten KATASTER-DETAIL: Delta T +, dann Zunahme von Verticillium longisporum, Sclerotinia sclerotiorum, Alternaria brassicae und Phoma lingam an Raps, Signal verstärkt im Szenarienzeitraum 2071-2100, Abnahme von Pyrenopeziza brassicae

Description: Simulierte und beobachtete Trends der jährlichen Hochwassermaxima KATASTER-BESCHREIBUNG: Trend der Zu- bzw. Abnahme der Andauer der jährlichen Hochwassermaxima in Deutschland für die Vergangenheit KATASTER-DETAIL: Abnahme des mittleren jährlichen Abflusses um 35 % in Baden-Württemberg (Pegel Achstetten/Baierzer Rot) bzw. 21 % in Brandenburg (Pegel Ketzin/Havel) Zunahme des mittleren jährlichen Abflusses um 84 % in Bayern (Pegel Breitenbachkamm/Breitach) bzw. 74 % in Bayern (Pegel Kalteneck/Ilz)

Description: Kalkulation der Hitzetage (Tmax 〉 30°C) anhand es PIK/DWD Datensatzes für 1951-2006 im Jahr, und für den Zeitraum 2051-60, Szenario A1B, als Mittel und Differenzkarten KATASTER-BESCHREIBUNG: Hitzetage (Tmax 〉 30°C) in Deutschland KATASTER-DETAIL: Zunahme der Hitzetage (Tmax 〉 30°C) 2051-2060 vs. 1951-2006 um bis zu 16 Tagen im Jahr, stärkste Zunahme Rheingragben, Rheinland-Pfalz, Niederrhein, Kölner Bucht und Mitteldeutschland

Description: Kalkulation der Klimatischen Wasserbilanz (mm) anhand es PIK/DWD Datensatzes für 1951-2006 im Jahr, und für den Zeitraum 2051-60, Szenario A1B, als Mittel und Differenzkarten KATASTER-BESCHREIBUNG: Jährliche Klimatischen Wasserbilanz WABI (Niederschlag - pot. Verdunstung nach Turc-Ivanov) für Deutschland KATASTER-DETAIL: Zu- bzw. Abnahme der (WABI) 2051-2060 vs. 1951-2006 von 200 - (-100) im Westen der BRD, in Ostdeutschland stärkere, einheitliche Abnahme der WABI um bis zu 300mmm

Description: Beispiele Ambrosia, Eichenprozessionsspinner KATASTER-BESCHREIBUNG: KATASTER-DETAIL:

Description: ausgedehnte Ambrosiaareale auch in der Lausitz und dem Berliner Raum KATASTER-BESCHREIBUNG: Neben Sensibilisierung gegen Ambrosia auch Kreuzreationen bei Sensibilisierung gegen Beifuß möglich KATASTER-DETAIL:

Description: einheimische und importierte  vektorassoziierte  Infektionen, Gastrointestinale  Infektionskrankheiten KATASTER-BESCHREIBUNG: KATASTER-DETAIL:

Description: weltweite Verbreitung der Asiatischen Tigermücke Aedes albopictus innerhalb der letzten zwei Jahrzehnte im Zusammenhang mit Chikungunya-Ausbruch im Sommer 2007 in Italien KATASTER-BESCHREIBUNG: Transportwege der Globalisierung als wesentlicher Faktor neben Klimaänderungen KATASTER-DETAIL:

Description: Gesundheitliche Bewertung ultravioletter Strahlung KATASTER-BESCHREIBUNG: KATASTER-DETAIL:

Description: Klärung der Studienlage zum potentiellen Einfluss des Klimawandels auf die Prävalenz von Haut- und Allergieerkrankungen in Deutschland KATASTER-BESCHREIBUNG: klimabedingte Veränderungen vor allem bei allergischen Erkrankungen, Hautkrebs und einzelnen erregerbedingten Dermatosen KATASTER-DETAIL:

Description: Fallbeispiel Sommer 2003 KATASTER-BESCHREIBUNG: Zunahme von Ozon in der Troposphäre bei stationären sommerlichen Hochdruckwetterlagen mit hohen Lufttemperaturen und intensiver Sonneneinstrahlung, indirekt Zunahme von Feinstaub bei Hitze (〉30°C) und Ozonbelastung (〉200 Mikrogramm pro Kubikmeter) KATASTER-DETAIL:

Description: UV-Strahlungsbeeinflussende Faktoren Azimutwinkel, Bewölkung, Aerosole, stratosphärisches Ozon, biologische Wirkung in Abhängigkeit vom Hauttyp und Sensibilisierung (Jahreszeit) KATASTER-BESCHREIBUNG: Einfluss klimatischer Veränderungen auf die Häufigkeit von Hautkrebserkrankungen sehr wahrscheinlich, bei vermutlich hoher Bedeutung des (thermisch motivierten) Expositionsverhaltens KATASTER-DETAIL:

Description: zeitliche Trends und geografische Ursprünge der Vektor-übertragenen Krankheiten in Deutschland im Hinblick auf Stärken der bestehenden Krankheitsüberwachung für Hantavirus Infektion (endemisch in Deutschland), Chikungunya-Fieber (vor kurzem Schwellenländer in Europa) und Dengue-Fieber (importiert aus tropischen Regionen) KATASTER-BESCHREIBUNG: KATASTER-DETAIL:

Description: Studie zu einer prognostizierten Anzahl von Tagen mit Wärme- und mit Kältestress, basierend auf Klimaszenarien für den Zeitraum 2071 bis 2100 KATASTER-BESCHREIBUNG: schätzungsweise durchschnittlicher Anstieg der Zahl der wärmeinduzierten Krankheitsfälle um einen Faktor von mehr als 3 und für hitzebedingte Krankenhausaufenthalte 6, Verlust von 0,1% bis 0.5% des BIP durch krankheitbedingten Arbeitsausfall KATASTER-DETAIL:

Description: Pollensaison, -auftreten und -arten, sowie Veränderungen der Allergenität von Pollen unter Klimawandel KATASTER-BESCHREIBUNG: zunehmende Polysensibilisierungen gegenüber Inhalationsallergien durch zunehmend invasives Traubenkraut Ambrosia artemisiifolia KATASTER-DETAIL:

Description: Studie zu einer prognostizierten Anzahl von Tagen mit Wärme- und mit Kältestress, basierend auf Klimaszenarien für den Zeitraum 2071 bis 2100 KATASTER-BESCHREIBUNG: Prognose: größere Zahl an Todesfällen durch Hitze im Süden gegenüber dem Norden Deutschlands und zugleich größerer Rückgang der Todesfälle durch Kälte im Norden, Anstieg der Todesopferzahl durch zunehmende Hitze insgesamt größer als Rückgang der Opferzahl durch weniger Kälte KATASTER-DETAIL:

Description: Autochthone Malaria in Deutschland, Historischer Abriss, Nachkriegsmalaria, Aktuelle malariaepidemiologische Situation KATASTER-BESCHREIBUNG: klimatische Bedingungen ermöglichen Ausreifung von Sporozoiten in heimischen Anophelesmücken, historisch erwiesen KATASTER-DETAIL:

Description: Herleitung einer Formel zur Berechnung der Plasmodium-Sporozoitenreifungszeit KATASTER-BESCHREIBUNG: Ausreifung von Pl. vivax- und Pl. falciparum-Sporozoiten im deutschen Raum möglich, Zustandekommen endemischer Malariaerregerübertragung bzw. Entstehung epidemiologisch wirksamer malariogener Potentiale dabei gebunden an das Vorhandensein von Gametozytenträgern und Überträgermücken KATASTER-DETAIL:

Description: Erfassung aller tatsächlichen oder vermuteten vektorassoziierten Krankheiten und Vektoren KATASTER-BESCHREIBUNG: viele Pathogene in Deutschland bereits vorhanden bzw. geeignete Vektoren stehen zur Verfügung, bei Einschleppung durch Reservoirwirte oder erkrankte Reisende sind autochthone Fälle zu erwarten KATASTER-DETAIL:

Description: deutliche Verschiebungen der phänologischen Jahreszeiten, besonders der Frühjahrsphasen; für jede phänologische Phase negative und auch positive Trends entdeckt, z.T. auf engen Raum; Verschiebung auf Variation der Lufttemperatur zurückzuführen; Verlängerung der Vegetationsperiode, hauptsächlich durch Veränderungen im Frühjahr KATASTER-BESCHREIBUNG: KATASTER-DETAIL:

Description: Abnahme des thermischen Einflusses auf den saisonalen Verlauf der Mortalität KATASTER-BESCHREIBUNG: sich verbessernde Bedingungen im Gesundheitswesen und bei der Innenraumtemperatur bedingen Abnahme des thermischen Einflusses insb. für Mortalitätszunahme bei niedrigen Temperaturen KATASTER-DETAIL:

Description: VORWORT ... 1 ; INHALTSVERZEICHNIS ... 2 ; 1 PÖHLMANN, G.: Basiskarten arider Gebiete ... 3 ; 2 MEISSNER, B.: Topographische Interpretation von Fernerkundungsdaten für "Basiskarten zur thematischen Kartierung arider Gebiete" ... 57 ; 3 MEISSNER, B. & RIPKE, U. : Luft- und Satellitenbild-Interpretation für die Karte "MUT 1 : 100 000"... 69 ; 4 KRAMER, G.: Topographische Ergänzungsmessungen ... 85 ; 5 RIPKE, U.: Die Herstellung des Kartenblattes MUT 1 : 100 000 ... 97 ; 6 ZIRN, V.: Höhenlinienstudie South Bir Tarfawi ... 105 ;

Description: research

Description: DFG, SUB Göttingen

Description: MEISSNER, B.: Fernerkundung bei der Grünplanung für die Stadtregion Berlin (West) ... 5 ; FIETZ, M. & MEISSNER, B.: Zur Auswertung von Color-Infrarot-Luftbildem (Berlin/West 1979) bei der Vegetationskartierung ... 23 ; FÖRSTER, U.: Vitalitätsbestimmung von Straßenbäumen. - Erfahrungen und Ergebnisse der Color-Infrarot-Bef 1 iegung in Berlin (West) 1979 ... 43 ; FIETZ, M.: Lebensbedingungen von Straßenbäumen in Berlin-Neukölln ... 53 ; BALTSCHUN, M. : Botanischer Garten - Karte der Gehölze - 1 : 1250 ... 65 ; BORYS, 6.: Karte zum Straßenbaumkataster - Berlin (West) - 1 : 2000 ... 101 ; ZEUNERT, C.: Karte zur Grünflächenplanung Berlin (West) - 1 : 4000 ... 121 ; MEISSNER, B.: Grünverteilung in Berlin (West) 1 : l0 000, eine Inventur - Bestandsaufnahme städtischer Vegetation mit Hilfe von reprotechnischen Mitteln und stark limitierter Bildinterpretation durch Color-Infrarot-Luftbilder... 141 ; MEISSNER, B., DOBBRICK, K. & MUNIER, C.: Satelliten-Fernerkundungs-Daten für städtische Grünübersicht? - Zur Einsatzfähigkeit von multispektralen Landsat-Scanner-Daten für jährliche Übersichts-Inventuren des Stadtgrüns von Berlin (West) ... 147 ; ANHANG ... 153 ;

Description: research

Description: DFG, SUB Göttingen

Description: Einer Anregung des 11. Arbeitskurses Niederdollendorf folgend, wurde eine Methode der Bearbeitung farbiger Originale kartographischer Landschaftsdarstellung entwickelt und erprobt. Eine erste Bestandsaufnahme hatte einen Bedarf an solchen Darstellungen bestätigt; geeignete Techniken stehen zur Verfügung, es fehlt jedoch eine lern- und lehrbare Methode der Bearbeitung, die unabhängig von der Person des Bearbeiters vergleichbare Ergebnisse liefert. Hier wurde nun ein in der thematischen Kartographie als Anleitung zu planmäßigen Vorgehen bewährtes System von Arbeitsschritten mit einigen Modifikationen als Richtlinie für die Bearbeitung von Landschaftskarten eingesetzt. Nicht zuletzt wird die Arbeitsweise von den verfügbaren Unterlagen beeinflußt und entweder der Ableitung topographischer Folgemaßstabskarten oder der freien Bearbeitung thematischer Karten entsprechen.

Description: According to a suggestion made by the 11th study group of Niederdollendorf a method of how to treat coloured originals of cartographic landscape representation has been developed and testet. A first stocktaking had confirmed the demand for such types of representation; although suitable techniques are available, a learnable and teachable method of treatment is needed which provides comparable results independent of the person incharge. In this case a slightly modified system of working steps has been used as a guideline for the treatment of maps which is a time-tested instruction for systematic procedure in thematic cartography. This method is not least influenced by the available records, corresponding either to a derivation of topographic maps on a consecutive scale or to the free treatment of thematic maps.

Description: PUHLMANN, G.: Eine Methode der Bearbeitung farbiger Originale kartographischer Landschaftsdarstellung ... 5 ; KOCHLER, J.: "Landschaften" in China und die Präzisierung dieser Kategorie in verschiedenen Typologien zur Gliederung des chinesischen Territoriums ... 13 ; STRAUB, W.: Eine Vegetationskarte der Volksrepublik China ... 23 ; MERTINS, M.: Eine Landschaftskarte der Volksrepublik China ... 71 ; BETKE, D. : Anmerkungen zu zwei kartographischen Neuerscheinungen zur Landnutzung und Vegetation der VR China ... 123 ;

Description: research

Description: DFG, SUB Göttingen

Description: einheimische Malaria als man-made-disease KATASTER-BESCHREIBUNG: KATASTER-DETAIL:

Description: Zusammenhang Kartoffelertrag und -qualität und Witterungsverlauf KATASTER-BESCHREIBUNG: Einfluss der Witterung (Temperatur, Niederschlag) auf den Ernteertrag KATASTER-DETAIL: Delta T (Mai, Juni) + und Delta Nied (Mai, Juni) -, dann Pflanzenentwicklung -; Delta Bodenfeuchte -, dann Wachstum -; Delta T (März, April) 〈 0°C, dann Schäden +;