ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Springer Science + Business Media  (120,015)
  • 1
    Publication Date: 2017-01-10
    Description: The structure of Alpine-type orogenic belts is widely assumed to have been strongly influenced by the inherited structure of the rifted continental margins from which they were formed. The challenge lies in deciphering these influences when orogenic contraction is strong. Contractional deformation in the Kamchia basin (SW Black Sea), caught between the Balkan orogenic belt and the stable Moesian block, has been arrested, preserving the early development of an Alpine-type orogen. We use 3D seismic and well-data to examine the tectonic and stratigraphic structure of this basin. Significant deformation has occurred underwater, through inversion tectonics within the basin itself. However, the basin margin structures have not reactivated. This margin is marked by a low-angle unconformity across which sediment was routed from the platform into the fledgling syn-orogenic basins. Such pathways may explain non-orogen-derived sediment within parts of the ancestral Apennine foredeep, for example. The role of platform margins to focus contractional deformation may have been over-emphasised elsewhere in the Alpine system. Further, the more strongly subsided portions of rifted margins may have accommodated significant contractional deformation through reactivation of basin faults. In the western Alps the complexity of structural juxapositions across thrust sheets in the Brianconnais may reflect these early-orogenic deformations rather than be the product of deformation that happened after tectonic burial. These early deformations are likely to be recorded in early syn-tectonic depositional sequences. ©2017 Swiss Geological Society〈br /〉〈br /〉〈a href="http://doi.org/10.1007/s00015-016-0238-z" target="_blank"〉〈img src="http://bib.telegrafenberg.de/typo3temp/pics/f2f773b55e.png" border="0"〉〈/a〉
    Print ISSN: 1661-8726
    Electronic ISSN: 1661-8734
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2017-01-07
    Description: This paper investigates hydrothermal fluid circulation in pre- and syn-tectonic sediments associated with detachments faults. The study area, located in the Err Nappe (SE-Switzerland), preserves a portion of the Adriatic distal margin. Two sites were studied in combining fieldwork, petrography, geochemistry and fluid inclusion analysis: the Piz Val Lunga and Fuorcla Cotschna areas. Both preserve relationships between a spectacularly exposed rift-related extensional detachment fault and its footwall and hangingwall that consist of extensional allochthons and syn- to post-tectonic sediments. These areas register a complex fluid flow history characterized by dolomitization, de-dolomitization, calcite cementation, dolomite and quartz veining and diffuse silicification. Meso- and micro-scale observations allow defining two steps in fluid evolution, which are related to Jurassic rift activity. A first carbonate-rich event occurred before the exhumation of the granitic basement, and this was followed by a second event marked by a change in the fluid towards a silica-dominated chemistry. Homogenization temperatures of fluid inclusions (average Th = 120−130 °C), negative δ18O values and a radiogenic 87Sr/86Sr signatures of carbonate minerals support the hypothesis that both the pre-tectonic rocks constituting the allochthons and the syn-tectonic sediments overlying the detachment fault were crossed by a flux of over-pressured hydrothermal fluids originating from seawater that penetrated into the basement through fault and fracture systems. Field relationships show that this fluid circulation started latest in middle Early Jurassic time, when fault activity migrated from the proximal to the future distal margin. We propose that it evolved chemically as a result of the involvement of the granitic basement forming the footwall of the extensional detachment system. Hydrothermal activity continued until the Middle/Late Jurassic, when tectonic activity shifted outwards leading to the exhumation of mantle rocks. This paper provides an original contribution to better understand the complex evolution of hyperextended continental rift domains and to constrain their thermal regimes. ©2017 Swiss Geological Society
    Print ISSN: 1661-8726
    Electronic ISSN: 1661-8734
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2016-02-15
    Description: Diurnal S $$1$$ 1 tidal oscillations in the coupled atmosphere–ocean system induce small perturbations of Earth’s prograde annual nutation, but matching geophysical model estimates of this Sun-synchronous rotation signal with the observed effect in geodetic Very Long Baseline Interferometry (VLBI) data has thus far been elusive. The present study assesses the problem from a geophysical model perspective, using four modern-day atmospheric assimilation systems and a consistently forced barotropic ocean model that dissipates its energy excess in the global abyssal ocean through a parameterized tidal conversion scheme. The use of contemporary meteorological data does, however, not guarantee accurate nutation estimates per se; two of the probed datasets produce atmosphere–ocean-driven S $$1$$ 1 terms that deviate by more than 30  $$upmu $$ μ as (microarcseconds) from the VLBI-observed harmonic of $$-16.2+i113.4$$ - 16.2 + i 113.4   $$upmu $$ μ as. Partial deficiencies of these models in the diurnal band are also borne out by a validation of the air pressure tide against barometric in situ estimates as well as comparisons of simulated sea surface elevations with a global network of S $$1$$ 1 tide gauge determinations. Credence is lent to the global S $$1$$ 1 tide derived from the Modern-Era Retrospective Analysis for Research and Applications (MERRA) and the operational model of the European Centre for Medium-Range Weather Forecasts (ECMWF). When averaged over a temporal range of 2004 to 2013, their nutation contributions are estimated to be $$-8.0+i106.0$$ - 8.0 + i 106.0   $$upmu $$ μ as (MERRA) and $$-9.4+i121.8$$ - 9.4 + i 121.8   $$upmu $$ μ as (ECMWF operational), thus being virtually equivalent with the VLBI estimate. This remarkably close agreement will likely aid forthcoming nutation theories in their unambiguous a priori account of Earth’s prograde annual celestial motion. ©2016 The Author(s)〈br /〉〈br /〉〈a href="http://doi.org/10.1007/s10712-016-9365-3" target="_blank"〉〈img src="http://bib.telegrafenberg.de/typo3temp/pics/f2f773b55e.png" border="0"〉〈/a〉
    Print ISSN: 0169-3298
    Electronic ISSN: 1573-0956
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2016-01-04
    Description: The FORMOSAT-3/COSMIC (F3/C) satellite probes the S4 scintillation index profile of GPS signals by using the radio occultation (RO) technique. In this study, for practical use on the Earth’s surface, a method is developed to convert and integrate the probed RO S4 index, so obtaining the scintillation on the ground. To estimate the worst case, the maximum value on each profile probed by F3/C, which is termed S4max, is isolated. The isolated data are further used to construct the global three-dimensional distributions of S4max for various local times, seasons, solar activities, and locations. The converted S4max for the first time estimates the global distribution of ionospheric scintillations in the GPS L1 band C/A code signal on the ground. The results show that the worst-case scintillations appear within the low-latitude region of ±30°N, peaking around ±20°N magnetic latitude; they begin at 1900 MLT, reach their maximum at 2100 MLT, and vanish by about 0200–0300 MLT. The most pronounced low-latitude scintillation occurs over the South American and African sectors. ©2015 Springer Science+Business Media Dordrecht
    Print ISSN: 0169-3298
    Electronic ISSN: 1573-0956
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2016-01-01
    Description: Magnetotelluric (MT) studies represent the structure of crust and mantle in terms of conductivity anomalies, while geodynamic modelling predicts the deformation and evolution of crust and mantle subject to plate tectonic processes. Here, we review the first attempts to link MT models with geodynamic models. An integration of MT with geodynamic modelling requires the use of relationships between conductivity and rheological parameters such as viscosity and melt fraction, which are provided by laboratory measurements of rock properties. Owing to present limitations in our understanding of these relationships, and in interpreting the trade-off between scale and magnitude of conductivity anomalies from MT inversions, most studies linking MT and geodynamic models are qualitative rather than providing hard constraints. Some recent examples attempt a more quantitative comparison, such as a study from the Himalayan continental collision zone, where rheological parameters have been calculated from a resistivity model and compared to predictions from geodynamic modelling. We conclude by demonstrating the potential in combining MT results and geodynamic modelling with examples that directly use MT results as constraints within geodynamic models of ore bodies and studies of an active volcano-tectonic rift. ©2015 Springer Science+Business Media Dordrecht
    Print ISSN: 0169-3298
    Electronic ISSN: 1573-0956
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2016-01-01
    Description: Electromagnetic methods that utilize controlled sources have been applied for natural resource exploration for more than a century. Nevertheless, concomitant with the recent adoption of marine controlled-source electromagnetics (CSEM) by the hydrocarbon industry, the overall usefulness of CSEM methods on land has been questioned within the industry. Truly, there are few published examples of land CSEM surveys carried out completely analogously to the current marine CSEM standard approach of towing a bipole source across an array of stationary receivers, continuously transmitting a low-frequency signal and interpreting the data in the frequency domain. Rather, different sensitivity properties of different exploration targets in diverse geological settings, gradual advances in theoretical understanding, acquisition and computer technology, and different schools in different parts of the world have resulted in a sometimes confusing multitude of land-based controlled-source EM surveying approaches. Here, I aim to review previous and present-day approaches, and provide reasoning for their diversity. I focus on surface-based techniques while excluding airborne EM and well logging and on applications for hydrocarbon exploration. Attempts at the very demanding task of using onshore controlled-source EM for reservoir monitoring are shown, and the possible future potential of EM monitoring is discussed. ©2015 Springer Science+Business Media Dordrecht
    Print ISSN: 0169-3298
    Electronic ISSN: 1573-0956
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2016-12-01
    Description: The Triassic in the “Médianes rigides” Nappe of the Swiss Prealps, belonging to the Briançonnais realm of the Western Alps, consists of a several hundred meters thick carbonate succession. At the localities Wiriehorn and Rothorn, 650 m above sequence base, the Costatoria goldfussi limestone, a remarkable coquina and widespread transgressive marker bed, yields the key conodont Sephardiella truempyi (HIRSCH), a proxy for the Curionii - lower Gredleri ammonoid Zones (Early Ladinian). This new discovery has deep implications on the age of the different Triassic formations in the Swiss Prealps and for its correlation with other tectonic units. The newly established Pralet Formation in the Swiss Prealps comprises the Balmi Member with the Lower Ladinian Costatoria goldfussi limestone at its base, followed by the dolomitic breccias of the Ladinian Erpilles Member. Below the S. truempyi level, both the mighty platform carbonate sequence of the Wiriehorn Formation in the Swiss Prealps, and of the coeval Champcella Formation in the Brianconnais realm, are reassigned here to the Late Anisian. In our revised correlation, the Costatoria goldfussi limestone corresponds to the main flooding surface (MFS) of the large marine transgression that correlates biostratigraphically the now well dated Upper Muschelkalk transgression in Provence, Sardinia and Spain with the basal Ladinian type locality at Bagolino in the Southern Alps. ©2016 Swiss Geological Society
    Print ISSN: 1661-8726
    Electronic ISSN: 1661-8734
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2016-11-16
    Description: The Panixer Pass Transverse Zone in the eastern Swiss Alps is oriented perpendicular to most alpine structures in the area. Its main element is the SSE-trending Crena-Martin Fold, a downward facing fold with Permian Verrucano in its core, which is cut by the Glarus Thrust. Hence Verrucano can be found below the Glarus Thrust in the Infrahelvetic Complex. Across the Panixer Pass Transverse Zone the structural buildup of the Infrahelvetic Complex changes considerably. Multiple published theories of the structural evolution are not satisfying particularly because traditional 2D geological cross-sections are insufficient to understand the 3D complexity. The main result and product of our study is a 3D structural model of the Panixer Pass Transverse Zone providing insight into its geometry. As modeling input, we produced a lithostratigraphic map and collected structural orientation data. The 3D structural model honors the observed surface geology and the expected 3D subsurface geometry. Our field data indicates that the shearing and transport direction was continuously NNW-directed, except for a phase of north-directed shearing during the early movement along the Glarus Thrust (late Calanda Phase) and related foliation development in the Helvetic Nappes. The Panixer Pass Transverse Zone developed prior to the penetrative foliation during a thrust-dominated deformation phase (Cavistrau Phase), for which we created a kinematic block model. According to this model, the Crena-Martin Fold is the result of multiple lateral ramps and related lateral fault-bend folds that all developed in a similar positon. In particular, we do not propose ENE-WSW-directed shortening to form the Crena-Martin Fold. The latter was finally cut at low angle by a dextral strike-slip fault to create the final geometry of the Panixer Pass Transverse Zone. Our kinematic model reproduces the main features of the 3D structural model and embeds well into previously proposed sequences of deformation phases. ©2016 Swiss Geological Society
    Print ISSN: 1661-8726
    Electronic ISSN: 1661-8734
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2016-09-01
    Description: Uniform geological datasets are a prerequisite for geological GIS analyses. Although the Geological Atlas of Switzerland 1:25,000 aims to supply spatial geological information nationwide, little effort has been undertaken in the past to harmonise this map series and its vector datasets. In the course of the HARMOS project, lithostratigraphic nomenclature was harmonised and standard map legends for a target scale of 1:25,000 were produced. This allows representing the lithostratigraphic units of Switzerland in a homogeneous way and sets a new reference in the lithostratigraphy of Switzerland. More than 40 experts in the field of regional stratigraphy contributed their knowledge to the project and, together with the Swiss Committee on Stratigraphy, guaranteed a high quality level. All results are presented in the Lithostratigraphic Lexicon of Switzerland, available cost-free online at http://www.strati.ch . By improving quality and accessibility of lithostratigraphic information, we supply a fundamental basis for the Swiss geological community and further research. ©2016 Swiss Geological Society
    Print ISSN: 1661-8726
    Electronic ISSN: 1661-8734
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2016-09-01
    Description: In the context of the harmonisation of the Swiss lithostratigraphic scheme, the Late Ladinian to Early Norian Bänkerjoch Formation and the Norian to Rhaetian Klettgau Formation of northern Switzerland are formally defined. The Bänkerjoch Formation replaces the «Gipskeuper». Delimitation generally follows the traditional Swiss scheme with the onset and offset of sulphate facies as basal and upper boundary. The Klettgau Formation includes six members (from base to top): The Ergolz Member (formerly «Schilfsandstein» and «Untere Bunte Mergel») consists of variegated silty dolomitic marl with dolocretes and channels filled by fine-grained sand of Scandinavian origin. The Gansingen Member (formerly «Gansinger Dolomit s.l.») starts with partly porous dolomite with Carnian bivalves and continues with an alternation of dolomite beds with thin dolomitic marl interlayers. At several places, the member has been eroded to great parts during the Late Triassic. Towards east and southeast, dolomitic sulphates, locally altered to dolomite or limestone, replace the marine carbonates. The Berlingen Member includes coarse alluvial and fluvial sandstones of Vindelician origin. It is restricted to the Lake Constance area. For practical reasons, the Gruhalde Member (formerly «Obere Bunte Mergel» and «Knollenmergel») encompasses all playa sediments above the Gansingen Member and Berlingen Member. Evidence in good outcrops suggests that it consists of several sedimentary cycles separated by long time spans of omission and erosion. The Seebi Member (formerly «Stubensandstein») includes layers of coarse-grained sandstones of Vindelician origin with calcitic, siliceous or clayey matrix. Locally, matrix fraction increases and becomes mostly dolomitic in the upper part. The Belchen Member (formerly «Rhät») consists of partly fossiliferous sandstone and greenish dark marl of estuarine to marine origin. Due to late Triassic and early Jurassic erosion, the Belchen Member is restricted to northwestern Switzerland and the Lake Constance area. ©2016 Swiss Geological Society
    Print ISSN: 1661-8726
    Electronic ISSN: 1661-8734
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Publication Date: 2016-11-05
    Description: The Jurassic ophiolites in the South Apuseni Mountains represent remnants of the Neotethys Ocean and belong to the East Vardar ophiolites that contain ophiolite fragments as well as granitoids and volcanics with island-arc affinity. New U–Pb zircon ages, and Sr and Nd isotope ratios give insights into their tectono-magmatic history. The ophiolite lithologies show tholeiitic MOR-type affinities, but are occasionally slightly enriched in Th and U, and depleted in Nb, which indicates that they probably formed in a marginal or back-arc basin. These ophiolites are associated with calc-alkaline granitoids and volcanics, which show trace element signatures characteristic for subduction-enrichment (high LILE, low HFSE). Low 87Sr/86Sr ratios (0.703836–0.704550) and high 143Nd/144Nd ratios (0.512599–0.512616) of the calc-alkaline series overlap with the ratios measured in the ophiolitic rocks (0.703863–0.704303 and 0.512496–0.512673), and hence show no contamination with continental crust. This excludes a collisional to post-collisional origin of the granitoids and is consistent with the previously proposed intra-oceanic island arc setting. The new U–Pb ages of the ophiolite lithologies (158.9–155.9 Ma, Oxfordian to Early Kimmeridgian) and granitoids (158.6–152.9 Ma, latest Oxfordian to Late Kimmeridgian) indicate that the two distinct magmatic series evolved within a narrow time range. It is proposed that the ophiolites and island arc granitoids formed above a long-lived NE-dipping subduction zone. A sudden flip in subduction polarity led to collision between island arc and continental margin, immediately followed by obduction of the ophiolites and granitoids on top of the continental margin of the Dacia Mega-Unit. Since the granitoids lack crustal input, they must have intruded the Apuseni ophiolites before both magmatic sequences were obducted onto the continental margin. The age of the youngest granitoid (~153 Ma, Late Kimmeridgian) yields an estimate for the maximum age of emplacement of the South Apuseni ophiolites and associated granitoids onto the Dacia Mega-Unit. ©2016 Swiss Geological Society
    Print ISSN: 1661-8726
    Electronic ISSN: 1661-8734
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Publication Date: 2016-09-01
    Description: During the late Early Cretaceous, the Jura domain was occupied by a photozoan carbonate platform, summarised in the Vallorbe Formation. From the earliest Aptian to the Late Cenomanian, open marine heterozoan and detrital marl, carbonate, and sandstone (up to 40 m thick) accumulated on top of the former Urgonian platform, followed during the Late Cretaceous by pelagic chalk and limestone. At the end of the Early Cretaceous, sediment accumulation was interrupted by several emersions and consecutive drowning phases identified in the field by angular discontinuities, iron crusts, and phosphatic conglomerates. Such sedimentary succession is particularly well visible in the present Bellegarde-sur-Valserine Basin of the Ain Department (eastern France). Therefore, in agreement with the Swiss Committee of Stratigraphy, we introduced new lithostratigraphic units to cover the time from the Aptian to the Cenomanian in the Jura mountains based on the type section near the historical outcrop of the Perte-du-Rhône in the Bellegarde Basin. The new Perte-du-Rhône Formation is subdivided in a lower marly unit (Fulie Member), followed by a middle green sandstone unit with phosphatic conglomerates (Mussel Member), which is finally topped by a mica-rich sandstone unit (Poncin Member). ©2016 Swiss Geological Society
    Print ISSN: 1661-8726
    Electronic ISSN: 1661-8734
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Publication Date: 2016-12-01
    Description: Surface exposure dating with a single cosmogenic nuclide relies on the assumption of simple constant exposure. In contrast, the combination of nuclides with different half-lives or production rate depth profiles allows constraining complex exposure histories. Here we present the systematics of how the combination of 10Be, in situ 14C and 36Cl can be used to understand both burial and erosion in a rock surface, in addition to yielding an exposure time. Concordant ages of all three nuclides characterize simple exposure. Apparently ‘too young’ 14C ages or ‘too old’ 36Cl ages indicate burial or erosion of the rock surface, respectively. We further report a first data set from a proglacial granite bedrock ridge in a small cirque in the Central Swiss Alps. Three samples were exposed for 9.6 ± 0.3 ka during the Holocene. The use of same-sample 10Be, in situ 14C and 36Cl allowed us to quantitatively show that these rock surfaces experienced simple constant exposure with ≤500 years of ice cover and ≤6 cm of erosion. In addition, the fact that samples inside and outside the Little Ice Age (LIA) ice extent yield indistinguishable ages reinforces the hypothesis that Grueben glacier reached comparable dimensions only briefly during the Holocene. Notably, at sites just inside of the LIA extent, which do exhibit fresh glacial polish, concordant ages suggest that subglacial erosion there was minimal. ©2016 Swiss Geological Society
    Print ISSN: 1661-8726
    Electronic ISSN: 1661-8734
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Publication Date: 2016-09-01
    Description: In the context of the harmonisation of the Swiss stratigraphic scheme (HARMOS project), the stratigraphic nomenclature of the Triassic sedimentary succession of northern Switzerland has been reorganised to six formations (from base to top): Dinkelberg, Kaiseraugst, Zeglingen, Schinznach, Bänkerjoch, and Klettgau Formation. The first three are formally introduced in this paper. The Dinkelberg Formation (formerly «Buntsandstein») encompasses the siliciclastic, mainly fluvial to coastal marine sediments of Olenekian to early Anisian age. The formation is some 100 m thick in the Basel area and wedges out towards southeast. The Kaiseraugst Formation (formerly «Wellengebirge») comprises fossiliferous siliciclastic and carbonate sediments documenting a marine transgressive—regressive episode in early Anisian time. It starts with sandstone, dolomite, continues with subtidal limestone and marl and ends with bituminous shale and supratidal dolomite. Thickness decreases from approximately 50 m in the High Rhine area to 10 m in the south and east. In the Lake Constance area, a transition to the siliciclastic marginal facies of the Vindelician High (Eschenbach Formation in Germany) is documented by borehole evidence. The Zeglingen Formation (formerly «Anhydritgruppe») documents a regressive marine evaporitic megacycle during the Illyrian (late Anisian). At most places, except in far eastern Switzerland, it starts with massive halite deposits. It continues with sulfate and marl sequences and ends with littoral stromatolitic dolomite. In the WSW–ENE trending depot centre total formation thickness is 150 m and more, and thickness of salt layers reaches up to 100 m. In the High Rhine area, the thickness is reduced due to subrecent subrosion. At some places evidence points to syn- to early-post-diagenetic erosion. For practical reasons, the six formations are organised in three lithostratigraphic groups: Buntsandstein Group (with the Dinkelberg Formation), Muschelkalk Group (combining the Kaiseraugst, Zeglingen and Schinznach Formations) and Keuper Group (combining the Bänkerjoch and Klettgau Formations). ©2016 Swiss Geological Society
    Print ISSN: 1661-8726
    Electronic ISSN: 1661-8734
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Publication Date: 2016-09-01
    Description: The sediments of late Anisian and Ladinian age in northern Switzerland, which were formerly named Upper Muschelkalk and Lower Keuper, mostly consist of carbonates. They accumulated in a transitional area between central parts of the Central European Epicontinental Basin and its margin towards the Vindelician Swell. Oolitic intervals imply the former presence of shoals or ramps in this region. They characterise this transitional region (“Alemannische Fazies”) together with dolomites in the upper part of the sedimentary succession. The total thickness usually varies between 50 and 85 m. A general decrease in thickness towards southeast has been found. The newly named Schinznach Formation is defined as a mappable unit of the upper part of the Muschelkalk Group. It is precisely introduced for those sedimentary rocks formerly named Upper Muschelkalk and Lower Keuper in northern Switzerland between the Doubs River and the Lake Biel in the west and the Lake Constance in the east. Within this formation the informal lithostratigraphic subdivisions currently in use should be replaced by new terms in accordance with the rules of lithostratigraphic nomenclature. In the scheme presented here the Schinznach Formation comprises 5 members and 5 beds. ©2016 Swiss Geological Society
    Print ISSN: 1661-8726
    Electronic ISSN: 1661-8734
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Publication Date: 2016-06-01
    Description: Excavations of Middle Triassic strata at Monte San Giorgio (Switzerland–Italy) have famously recovered a range of reptiles whose affinities, morphology and preservation have been extensively described. The locality has also yielded a contemporaneous and equally diverse fish fauna that has yet to be described to the same degree. To address this imbalance, a taphonomic study was undertaken using the actinopterygian Saurichthys , a relatively abundant taxon found in the Besano Formation (latest Anisian–earliest Ladinian) and Cassina Beds of the Meride Formation (early Ladinian). Specimens from each horizon were scored for articulation and completeness across ten anatomical units, the resulting datasets being used to determine a taphonomic model and investigate preservational variation through time. Saurichthys showing moderate to high articulation and high completeness occur in both horizons but states of low articulation and moderate completeness are only present in the Besano Formation. The same feature is apparent in corresponding unit plots, suggesting different environmental conditions were present during deposition of each horizon, specifically those that reduced articulation and completeness during a prolonged residence on the sediment surface. ©2015 Swiss Geological Society
    Print ISSN: 1661-8726
    Electronic ISSN: 1661-8734
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Publication Date: 2016-04-01
    Description: The present study provides an evaluation of the regional differences over China in surface energy budget components as simulated by a selection of models from phase five of the Coupled Model Intercomparison Project (CMIP5), covering the period 1960–2005. Similarities and differences exist among the models in terms of both spatial and magnitude patterns. For climatology, the CMIP5 models show quite different spatial distributions of shortwave radiation and sensible heat flux. In terms of seasonal variation, the surface energy budgets are remarkably different between western and eastern China. The discrepancies in the seasonal variation of sensible heat flux are mainly attributable to temperature differences and wind speed, while those of shortwave radiation are caused by the seasonal variation in total cloud cover. Cloudiness is one of the most crucial parameters in estimating the surface energy budget. In addition, the study also reveals that the magnitudes of the various components show larger (more than two-fold) differences between western and eastern parts of China, especially in net longwave and upward shortwave radiation, as well as latent and sensible heat fluxes. The results for surface soil heat flux show that there is more incoming energy during spring and summer and more outgoing energy during fall and winter in both western and eastern China. Furthermore, compared to NCEP2 data, the ERA-40 reanalysis product produces results more similar to the multi-model ensemble mean for most components. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Publication Date: 2016-04-02
    Description: Despite much previous effort, the establishment of an accurate model of the western Pacific subtropical high (WPSH) and analysis of its chaotic behavior has proved to be difficult. Based on a phase-space technique, a nonlinear dynamical model of the WPSH ridge line and summer monsoon factors is constructed here from 50 years of data. Using a genetic algorithm, model inversion and parameter optimization are performed. The Lyapunov spectrum, phase portraits, time history, and Poincaré surface of section of the model are analyzed and an initial-value sensitivity test is performed, showing that the model and data have similar phase portraits and that the model is robust. Based on equilibrium stability criteria, four types of equilibria of the model are analyzed. Bifurcations and catastrophes of the equilibria are studied and related to the physical mechanism and actual weather phenomena. The results show that the onset and enhancement of the Somali low-level jet and the latent heat flux of the Indian monsoon are among the most important reasons for the appearance and maintenance of the double-ridge phenomenon. Violent breakout and enhancement of the Mascarene cold high will cause the WPSH to jump northward, resulting in the “empty plum” phenomenon. In the context of bifurcation and catastrophe in the dynamical system, the influence of the factors considered here on the WPSH has theoretical and practical significance. This work also opens the way to new lines of research on the interaction between the WPSH and the summer monsoon system. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    Publication Date: 2016-04-01
    Description: In this paper, validation of rain climatic zone classifications for Nigeria is presented based on global radio-climatic models by the International Telecommunication Union-Radiocommunication (ITU-R) and Crane. Rain rate estimates deduced from several ground-based measurements and those earlier estimated from the precipitation index on the Tropical Rain Measurement Mission (TRMM) were employed for the validation exercise. Although earlier classifications indicated that Nigeria falls into zones P, Q, N, and K for the ITU-R designations, and zones E and H for Crane’s climatic zone designations, the results however confirmed that the rain climatic zones across Nigeria can only be classified into four, namely P, Q, M, and N for the ITU-R designations, while the designations by Crane exhibited only three zones, namely E, G, and H. The ITU-R classification was found to be more suitable for planning microwave and millimeter wave links across Nigeria. The research outcomes are vital in boosting the confidence level of system designers in using the ITU-R designations as presented in the map developed for the rain zone designations for estimating the attenuation induced by rain along satellite and terrestrial microwave links over Nigeria. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    Publication Date: 2016-04-01
    Description: During the Indian monsoon season, organized convection in the form of inter-tropical convergence zone (ITCZ) originates from the equatorial trough (ET) region over the equatorial Indian Ocean, propagates northward towards the heated Indian landmass at intraseasonal timescales (30–60 days). In this paper, the long-term changes in rainfall over the ET region during the northern summer season has been investigated for a 34-year (1979–2012) period using gauge-adjusted multisatellite Global Precipitation Climatology Project (GPCP) rainfall data set. Rainfall over this region shows a pronounced seasonality and the eastern ET (EET) receives higher rainfall than the western ET (WET) during the northern summer season. Moreover, the northern summer rainfall over the WET and EET are not significantly correlated with each other. Linear trend analysis of domain-mean seasonal rainfall shows a statistically significant increasing trend of 0.4 mm day−1 decade−1 during the northern summer over the WET, whereas no significant trend is observed over the EET. The long-term changes in the associated variables linked through the moisture budget equation are also examined over both regions of ET for the study period. Even though evaporation over both WET and EET shows statistically significant increasing trend associated with an increase in sea surface temperature and near-surface wind, the vertically integrated moisture convergence shows no significant change over the WET whereas it shows a decrease over the EET during the study period. These might be the possible reasons behind a significant increase in rainfall over the WET with an insignificant change in rainfall over the EET. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Publication Date: 2016-02-01
    Description: We developed a tree-ring width chronology from pine trees ( Pinus tabulaeformis and Pinus armandii ) stand near the peaks of Huashan, Shaanxi, north-central China. Growth-climate response analyses showed that the radial growth of pine trees is mainly influenced by April–June precipitation. A model to reconstruct precipitation based on tree widths was constructed, accounting for 55 % of the instrumental variance during the period 1953–2012. Spatial correlation analyses between the reconstruction and observed gridded precipitation data shows that the seasonal precipitation reconstruction captures regional climatic variations over north China. Compared with the historical archives and other tree-ring records in north China, many large-scale drought events, linked to the El Niño–Southern Oscillation (ENSO), were found. Many of these events have had profound impacts on the people of north China over the past several centuries. Composite maps of sea surface temperatures and 500 hPa geopotential heights for selected extremely dry and wet years in Huashan show characteristics similar to those related to the ENSO patterns, particularly with regard to ocean and atmospheric conditions in the equatorial and north Pacific. Our 531-year precipitation reconstruction for Huashan provides a long-term perspective on current and 20th century wet and dry events in north China, and is useful to guide expectations of future variability, and helps us to address climate change. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Publication Date: 2016-02-01
    Description: Extreme precipitation has been reported to occur more frequently, and intensified extreme precipitation can cause considerable socioeconomic losses. Extreme precipitation can be measured by the concentration index (CI) and the precipitation concentration index (PCI). The former indicates the degree to which daily precipitation is unevenly distributed in the time domain, and the latter represents the degree to which monthly precipitation is unevenly distributed throughout the year. In this paper, we analyzed spatiotemporal characteristics of extreme precipitation by using CI and PCI and examined whether links exist between extreme precipitation and urban extent. We found that the spatial patterns of PCI and CI are different over China. The two are consistent in being high in Northeast China and low in Southwest China. However, they differ significantly; Northwest China is where CI is low but PCI is high, which indicates that precipitation is highly concentrated in a few months of the year, but daily precipitation is more evenly distributed during the wet season in Northwest China. The trends of both PCI and annual CI are spatially heterogeneous and are significant at the 90 % confidence level for approximately 20 % of China, and seasonal CI exhibits very different trends. Possible links between precipitation concentration and urbanization are investigated by analyzing the correlation coefficient between CI (PCI) and population density. Precipitation concentration is found positively correlated with urbanization at the 99 % confidence level in the three selected regions. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Publication Date: 2016-01-26
    Description: Large-scale atmospheric patterns are examined on orbital timescales using a climate model which explicitly resolves the atmosphere–ocean–sea ice dynamics. It is shown that, in contrast to boreal summer where the climate mainly follows the local radiative forcing, the boreal winter climate is strongly determined by modulation of circulation modes linked to the Arctic Oscillation/North Atlantic Oscillation (AO/NAO) and the Northern/Southern Annular Modes. We find that during a positive phase of the AO/NAO the convection in the tropical Pacific is below normal. The related atmospheric circulation provides an atmospheric bridge for the precessional forcing inducing a non-uniform temperature anomalies with large amplitudes over the continents. We argue that this is important for mechanisms responsible for multi-millennial climate variability and glacial inception. ©2016 The Author(s)〈br /〉〈br /〉〈a href="http://doi.org/10.1007/s00704-015-1725-2" target="_blank"〉〈img src="http://bib.telegrafenberg.de/typo3temp/pics/f2f773b55e.png" border="0"〉〈/a〉
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Publication Date: 2016-01-21
    Description: The popular picture of the greenhouse effect emphasises the radiation transfer but fails to explain the observed climate change. An old conceptual model for the greenhouse effect is revisited and presented as a useful resource in climate change communication. It is validated against state-of-the-art data, and nontraditional diagnostics show a physically consistent picture. The earth’s climate is constrained by well-known and elementary physical principles, such as energy balance, flow, and conservation. Greenhouse gases affect the atmospheric optical depth for infrared radiation, and increased opacity implies higher altitude from which earth’s equivalent bulk heat loss takes place. Such an increase is seen in the reanalyses, and the outgoing long-wave radiation has become more diffuse over time, consistent with an increased influence of greenhouse gases on the vertical energy flow from the surface to the top of the atmosphere. The reanalyses further imply increases in the overturning in the troposphere, consistent with a constant and continuous vertical energy flow. The increased overturning can explain a slowdown in the global warming, and the association between these aspects can be interpreted as an entanglement between the greenhouse effect and the hydrological cycle, where reduced energy transfer associated with increased opacity is compensated by tropospheric overturning activity. ©2016 The Author(s)〈br /〉〈br /〉〈a href="http://doi.org/10.1007/s00704-016-1732-y" target="_blank"〉〈img src="http://bib.telegrafenberg.de/typo3temp/pics/f2f773b55e.png" border="0"〉〈/a〉
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Publication Date: 2016-01-28
    Description: A weather-type catalogue based on the Jenkinson and Collison method was developed for an area in south-west Russia for the period 1961–2010. Gridded sea level pressure data was obtained from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis. The resulting catalogue was analysed for frequency of individual types and groups of weather types to characterise long-term atmospheric circulation in this region. Overall, the most frequent type is anticyclonic (A) (23.3 %) followed by cyclonic (C) (11.9 %); however, there are some key seasonal patterns with westerly circulation being significantly more common in winter than summer. The utility of this synoptic classification is evaluated by modelling daily rainfall amounts. A low level of error is found using a simple model based on the prevailing weather type. Finally, characteristics of the circulation classification are compared to those for the original JC British Isles catalogue and a much more equal distribution of flow types is seen in the former classification. ©2016 The Author(s)〈br /〉〈br /〉〈a href="http://doi.org/10.1007/s00704-015-1711-8" target="_blank"〉〈img src="http://bib.telegrafenberg.de/typo3temp/pics/f2f773b55e.png" border="0"〉〈/a〉
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    Publication Date: 2016-01-29
    Description: Potential evapotranspiration (PET) is one of the most critical parameters in the research on agro-ecological systems. The computational methods for the estimation of PET vary in data demands from very simple (empirically based), requiring only information based on air temperatures, to complex ones (more physically based) that require data on radiation, relative humidity, wind speed, etc. The current research is focused on three study areas in Greece that face different climatic conditions due to their location. Twelve PET formulae were used, analyzed and inter-compared in terms of their sensitivity regarding their input coefficients for the Ardas River basin in north-eastern Greece, Sperchios River basin in Central Greece and Geropotamos River basin in South Greece. The aim was to compare all the methods and conclude to which empirical PET method(s) better represent the PET results in each area and thus should be adopted and used each time and which factors influence the results in each case. The results indicated that for the areas that face Mediterranean climatic conditions, the most appropriate method for the estimation of PET was the temperature-based, Hamon’s second version (PETHam2). Furthermore, the PETHam2 was able to estimate PET almost similarly to the average results of the 12 equations. For the Ardas River basin, the results indicated that both PETHam2 and PETHam1 can be used to estimate PET satisfactorily. Moreover, the temperature-based equations have proven to produce better results, followed by the radiation-based equations. Finally, PETASCE, which is the most commonly used PET equation, can also be applied occasionally in order to provide satisfactory results. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Publication Date: 2016-01-26
    Description: The eddy covariance technique was used to measure the CO2 flux over four differently grazed Leymus chinensis steppe ecosystems (ungrazed since 1979 (UG79), winter grazed (WG), continuously grazed (CG), and heavily grazed (HG) sites) during four growing seasons (May to September) from 2005 to 2008, to investigate the response of the net ecosystem exchange (NEE) over grassland ecosystems to meteorological factors and grazing intensity. At UG79, the optimal air temperature for the half-hourly NEE occurred between 17 and 20 °C, which was relatively low for semi-arid grasslands. The saturated NEE (NEEsat) and temperature sensitivity coefficient ( Q 10) of ecosystem respiration (RE) exhibited clear seasonal and interannual variations, which increased with canopy development and the soil water content (SWC, at 5 cm). The total NEE values for the growing seasons from 2005 to 2008 were −32.0, −41.5, −66.1, and −89.8 g C m−2, respectively. Both the amounts and distribution of precipitation during the growing season affected the NEE. The effects of grazing on the CO2 flux increased with the grazing intensity. During the peak growth stage, heavy grazing and winter grazing decreased NEEsat and gross primary production (45 % for HG and 34 % for WG) due to leaf area removal. Both RE and Q 10 were clearly reduced by heavy grazing. Heavy grazing changed the ecosystem from a CO2 sink into a CO2 source, and winter grazing reduced the total CO2 uptake by 79 %. In the early growing season, there was no difference in the NEE between CG and UG79. In addition to the grazing intensity, the effects of grazing on the CO2 flux also varied with the vegetation growth stages and SWC. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Publication Date: 2016-01-18
    Description: The Huai River basin is one of the major supplier of agricultural products in China, and droughts have critical impacts on agricultural development. Good knowledge of drought behaviors is of great importance in the planning and management of agricultural activities in the Huai River basin. With the copula functions to model the persistence property of drought, the probabilistic seasonal drought forecasting models have been built in the Huai River basin. In this study, droughts were monitored by the Standardized Precipitation Evapotranspiration Index (SPEI) with the time scales of 3, 6, and 9 months, and their composite occurrence probability has been used to forecast the seasonal drought. Results indicated that the uncertainty related to the predicted seasonal drought is larger when more severe droughts occurred in the previous seasons, and the severe drought which occurs in summer and autumn will be more likely to be persistent in the next season while the severe drought in winter and spring will be more likely to be recovered in the subsequent season. Furthermore, given the different drought statuses in the previous season, spatial patterns of the predicted drought events with the largest occurrence probability have also been investigated, and results indicate that the Huai River basin is vulnerable to the extreme drought in most parts of the basin, e.g., the severe drought in winter will be more likely to be persistent in spring in the central part of the southern Huai River basin. Such persistent drought events pose serious challenges for planning and management of agricultural irrigation, then results of the study will be valuable for the planning of crop cultivation or mitigation of the losses caused by drought in the Huai River basin, China. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Publication Date: 2016-01-16
    Description: This study describes warm spells in Northern Europe and determines the synoptic situations that cause their occurrence. In this article, a relatively warm day was defined as a day when the maximum temperature exceeded the 95th annual percentile, and a warm spell (WS) was considered to be a sequence of at least five relatively warm days. In the analysed multiannual period and within the investigated area, 24 (Kallax) to 53 (Oslo) WSs were observed. The occurrence of WSs was mainly connected with positive anomalies of sea level pressure and a 500-hPa isobaric surface, displaying the presence of high-pressure systems. This occurrence was also accompanied by positive T850 anomalies. ©2016 The Author(s)〈br /〉〈br /〉〈a href="http://doi.org/10.1007/s00704-015-1727-0" target="_blank"〉〈img src="http://bib.telegrafenberg.de/typo3temp/pics/f2f773b55e.png" border="0"〉〈/a〉
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Publication Date: 2016-01-18
    Description: The potential of using land surface models (LSMs) to monitor near-real-time drought has not been fully assessed in China yet. In this study, we analyze the performance of such a system with a land surface model (LSM) named the Australian Community Atmosphere Biosphere Land Exchange model (CABLE). The meteorological forcing datasets based on reanalysis products and corrected by observational data have been extended to near-real time for semi-operational trial. CABLE-simulated soil moisture (SM) anomalies are used to characterize drought spatial and temporal evolutions. One outstanding feature in our analysis is that with the same meteorological data, we have calculated a range of drought indices including Standardized Precipitation Index (SPI), Standardized Precipitation-Evapotranspiration Index (SPEI), Palmer Drought Severity Index (PDSI). We have assessed the similarity among these indices against observed SM over a number of regions in China. While precipitation is the dominant factor in the drought development, relationships between precipitation, evaporation, and soil moisture anomalies vary significantly under different climate regimes, resulting in different characteristics of droughts in China. The LSM-based trial system is further evaluated for the 1997/1998 drought in northern China and 2009/2010 drought in southwestern China. The system can capture the severities and temporal and spatial evolutions of these drought events well. The advantage of using a LSM-based drought monitoring system is further demonstrated by its potential to monitor other consequences of drought impacts in a more physically consistent manner. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Publication Date: 2016-01-26
    Description: In this study, 43-year (1965–2007) monthly and annual rainfall time series of ten rainfall stations in a semi-arid region of western India are analyzed by adopting three tests for testing normality and by applying autoregressive technique for exploring persistence. Gradual trends are identified by three tests, and their magnitudes are assessed by the Sen’s slope estimator. Also, abrupt changes are detected by using four tests and they are further confirmed by two tests. Box-whisker plots revealed that the rainfalls of June and September are right skewed for all the stations. The annual rainfalls of Bhinder, Dhariawad, and Gogunda stations are found considerably right skewed. The normality tests indicated that the rainfall of July does not deviate from the normal distribution at all the stations. However, the annual rainfall is found non-normal at five stations. The monthly rainfalls of June, July, and August have persistence respectively at three (Mavli, Salumber, and Sarada), two (Kherwara and Sarada), and one (Mavli) stations, whereas the annual rainfall has persistence at Girwa and Mavli stations. Significantly increasing trend is detected at Mavli in the rainfall of July and in the annual rainfall ( p value 〉 0.05), while the negative trend in August rainfall at Dhariawad is found significant ( p value 〉 0.10). This study revealed that the presence of serial correlation does not affect the performance of the Mann-Kendall test. Mean values of trend magnitudes for the rainfalls of June, July, August, and September are 0.3, 0.8, −0.4, and 0.4 mm year−1, respectively, and the overall mean value for the annual rainfall is 0.9 mm year−1. It is found that the standard normal homogeneity test and the Pettitt test are biased towards the end of the series to locate a change point. Conversely, the Bayesian test has a tendency to look for a change point in the beginning of time series. Confirmed abrupt changes in the rainfall time series are found in the year 2003 (Bhinder) in June; years 1974 (Mavli) and 1989 (Dhariawad and Salumber) in July; years 1972 (Sarada), 1990 (Dhariawad), and 2003 (Mavli) in August; years 1977 (Dhariawad), 1991 (Sarada), and 2004 (Kotra) in September; and in the year 1972 (Mavli and Sarada stations) in the annual series. It is emphasized that the significantly increasing trend of rainfall may have linkages with climate change and/or variability. Finally, this study recommends use of multiple statistical tests for analyzing hydrologic time series in order to ensure reliable decisions. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    Publication Date: 2016-01-14
    Description: An important source of uncertainty, which causes further uncertainty in numerical simulations, is that residing in the parameters describing physical processes in numerical models. Therefore, finding a subset among numerous physical parameters in numerical models in the atmospheric and oceanic sciences, which are relatively more sensitive and important parameters, and reducing the errors in the physical parameters in this subset would be a far more efficient way to reduce the uncertainties involved in simulations. In this context, we present a new approach based on the conditional nonlinear optimal perturbation related to parameter (CNOP-P) method. The approach provides a framework to ascertain the subset of those relatively more sensitive and important parameters among the physical parameters. The Lund–Potsdam–Jena (LPJ) dynamical global vegetation model was utilized to test the validity of the new approach in China. The results imply that nonlinear interactions among parameters play a key role in the identification of sensitive parameters in arid and semi-arid regions of China compared to those in northern, northeastern, and southern China. The uncertainties in the numerical simulations were reduced considerably by reducing the errors of the subset of relatively more sensitive and important parameters. The results demonstrate that our approach not only offers a new route to identify relatively more sensitive and important physical parameters but also that it is viable to then apply “target observations” to reduce the uncertainties in model parameters. ©2016 The Author(s)〈br /〉〈br /〉〈a href="http://doi.org/10.1007/s00704-015-1690-9" target="_blank"〉〈img src="http://bib.telegrafenberg.de/typo3temp/pics/f2f773b55e.png" border="0"〉〈/a〉
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    Publication Date: 2016-04-01
    Description: Large biases associated with climate projections are problematic when it comes to their regional application in the assessment of water resources and ecosystems. Here, we demonstrate a method that can reduce systematic biases in regional climate projections. The global and regional climate models employed to demonstrate the technique are the Community Climate System Model (CCSM) and the Weather Research and Forecasting (WRF) model. The method first utilized a statistical regression technique and a global reanalysis dataset to correct biases in the CCSM-simulated variables (e.g., temperature, geopotential height, specific humidity, and winds) that are subsequently used to drive the WRF model. The WRF simulations were conducted for the western United States and were driven with (a) global reanalysis, (b) original CCSM, and (c) bias-corrected CCSM data. The bias-corrected CCSM data led to a more realistic regional climate simulation of precipitation and associated atmospheric dynamics, as well as snow water equivalent (SWE), in comparison to the original CCSM-driven WRF simulation. Since most climate applications rely on existing global model output as the forcing data (i.e., they cannot re-run or change the global model), which often contain large biases, this method provides an effective and economical tool to reduce biases in regional climate downscaling simulations of water resource variables. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    Publication Date: 2016-04-01
    Description: In a positively long-range correlated process, variations among consecutive steps are interdependent, especially the influence of previous one-step variation on next steps. How to quantify this kind of impact is of great importance to predict the future variations. In this paper, we demonstrate that this kind of impact depends on the memory strength of underlying processes from two aspects based on the theoretical and observational calculations. More precisely, the conditional calculations and the marginal distribution of the next step variation with given distribution of the previous one-step variation. Both the theoretical and observational calculations demonstrate that the previous one-step variation affect greatly the variation for the next one-step, and the expectation of next step variation will shift to larger value as the increase of memory strength but with a much smaller uncertainty. This is beneficial for our one-step ahead prediction, and will be especially beneficial for multi-step ahead prediction. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    Publication Date: 2016-04-01
    Description: Reference evapotranspiration (ETo) is an important variable in hydrological modeling, which is not always available, especially for ungauged catchments. Satellite data, such as those available from the MODerate Resolution Imaging Spectroradiometer (MODIS), and global datasets via the European Centre for Medium Range Weather Forecasts (ECMWF) reanalysis (ERA) interim and National Centers for Environmental Prediction (NCEP) reanalysis are important sources of information for ETo. This study explored the seasonal performances of MODIS (MOD16) and Weather Research and Forecasting (WRF) model downscaled global reanalysis datasets, such as ERA interim and NCEP-derived ETo, against ground-based datasets. Overall, on the basis of the statistical metrics computed, ETo derived from ERA interim and MODIS were more accurate in comparison to the estimates from NCEP for all the seasons. The pooled datasets also revealed a similar performance to the seasonal assessment with higher agreement for the ERA interim ( r  = 0.96, RMSE = 2.76 mm/8 days; bias = 0.24 mm/8 days), followed by MODIS ( r  = 0.95, RMSE = 7.66 mm/8 days; bias = −7.17 mm/8 days) and NCEP ( r  = 0.76, RMSE = 11.81 mm/8 days; bias = −10.20 mm/8 days). The only limitation with downscaling ERA interim reanalysis datasets using WRF is that it is time-consuming in contrast to the readily available MODIS operational product for use in mesoscale studies and practical applications. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    Publication Date: 2016-04-01
    Description: Increases in the atmospheric CO2 concentration affect both the global climate and plant metabolism, particularly for high-altitude ecosystems. Because of the limitations of field experiments, it is difficult to evaluate the responses of vegetation to CO2 increases and separate the effects of CO2 and associated climate change using direct observations at a regional scale. Here, we used the Community Earth System Model (CESM, version 1.0.4) to examine these effects. Initiated from bare ground, we simulated the vegetation composition and productivity under two CO2 concentrations (367 and 734 ppm) and associated climate conditions to separate the comparative contributions of doubled CO2 and CO2-induced climate change to the vegetation dynamics on the Tibetan Plateau (TP). The results revealed whether the individual effect of doubled CO2 and its induced climate change or their combined effects caused a decrease in the foliage projective cover (FPC) of C3 arctic grass on the TP. Both doubled CO2 and climate change had a positive effect on the FPC of the temperate and tropical tree plant functional types (PFTs) on the TP, but doubled CO2 led to FPC decreases of C4 grass and broadleaf deciduous shrubs, whereas the climate change resulted in FPC decrease in C3 non-arctic grass and boreal needleleaf evergreen trees. Although the combination of the doubled CO2 and associated climate change increased the area-averaged leaf area index (LAI), the effect of doubled CO2 on the LAI increase (95 %) was larger than the effect of CO2-induced climate change (5 %). Similarly, the simulated gross primary productivity (GPP) and net primary productivity (NPP) were primarily sensitive to the doubled CO2, compared with the CO2-induced climate change, which alone increased the regional GPP and NPP by 251.22 and 87.79 g C m−2 year−1, respectively. Regionally, the vegetation response was most noticeable in the south-eastern TP. Although both doubled CO2 and associated climate change had a generally positive effect on LAI, GPP and NPP, it should be noted that the climate change had a somewhat negative effect on the vegetation structure and productivity of the TP. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
  • 38
    Publication Date: 2016-04-01
    Description: The goal of the Search for an Astronomical Site in Kenya (SASKYA) project is to identify the best possible site(s) in Kenya for astronomical optical observation, using ERA-interim climate reanalyses and high-resolution UK Met Office Africa Limited Area meteorological model (Africa-LAM) data. This initial search focusses on a selection of 13 candidate mountain peaks across Kenya. A mixture of 30 years (1981–2010) of relatively coarse-grained ERA-interim reanalyses data and 12 months’ (2011–2012) of much higher resolution UK Met Office Africa-LAM data were used to determine the best possible sites. Cloud cover, precipitable water vapour (specific humidity), vertical velocity, aerosol loadings and wind data were analysed. The results confirm that many sites in Kenya are reasonably cloud free, with estimated photometric night fractions of possibly 50 % at the best sites. Significant seasonal inter-annual and inter-decadal variations in cloud cover can be expected, however. Average precipitable water vapour (PWV) values are uncomfortably high, but periods of much lower PWV can be expected during favourable conditions in the dry seasons. Long-term vertical velocities (as a proxy to determine areas of improved “seeing” conditions) indicate that good astronomical viewing conditions are likely to be dependent on the season and wind direction across Kenya. Finally, after full consideration of the climatological data, a trade-off is expected between the best possible site in climatological terms, and the practicalities of installing remote equipment in isolated, inaccessible areas with little or no infrastructure. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Publication Date: 2016-03-30
    Description: The purpose of this study is to revaluate the changing spatial and temporal trends of precipitation in Turkey. Turkey is located in one of the regions at greatest risk from the potential effects of climate change. Since the 1970s, a decreasing trend in annual precipitation has been observed, in addition to an increasing number of precipitation-related natural hazards such as floods, extreme precipitation, and droughts. An understanding of the temporal and spatial characteristics of precipitation is therefore crucial to hazard management as well as planning and managing water resources, which depend heavily on precipitation. The ordinary kriging method was employed to interpolate precipitation estimates using precipitation records from 228 meteorological stations across the country for the period 1976–2010. A decreasing trend was observed across the Central Anatolian region, except for 1996–2000 which saw an increase in precipitation. However, this same period is identified as the driest year in Eastern and South Eastern Anatolia. The Eastern Black Sea region has the highest precipitation in the country; after 1996, an increase in annual precipitation in this region is observed. An overall reduction is also seen in southwest Turkey, with less variation in precipitation. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    Publication Date: 2016-03-29
    Description: Downscaling precipitation is required in local scale climate impact studies. In this paper, a statistical downscaling scheme was presented with a combination of geographically weighted regression (GWR) model and a recently developed method, high accuracy surface modeling method (HASM). This proposed method was compared with another downscaling method using the Coupled Model Intercomparison Project Phase 5 (CMIP5) database and ground-based data from 732 stations across China for the period 1976–2005. The residual which was produced by GWR was modified by comparing different interpolators including HASM, Kriging, inverse distance weighted method (IDW), and Spline. The spatial downscaling from 1° to 1-km grids for period 1976–2005 and future scenarios was achieved by using the proposed downscaling method. The prediction accuracy was assessed at two separate validation sites throughout China and Jiangxi Province on both annual and seasonal scales, with the root mean square error (RMSE), mean relative error (MRE), and mean absolute error (MAE). The results indicate that the developed model in this study outperforms the method that builds transfer function using the gauge values. There is a large improvement in the results when using a residual correction with meteorological station observations. In comparison with other three classical interpolators, HASM shows better performance in modifying the residual produced by local regression method. The success of the developed technique lies in the effective use of the datasets and the modification process of the residual by using HASM. The results from the future climate scenarios show that precipitation exhibits overall increasing trend from T1 (2011–2040) to T2 (2041–2070) and T2 to T3 (2071–2100) in RCP2.6, RCP4.5, and RCP8.5 emission scenarios. The most significant increase occurs in RCP8.5 from T2 to T3, while the lowest increase is found in RCP2.6 from T2 to T3, increased by 47.11 and 2.12 mm, respectively. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    Publication Date: 2016-04-01
    Description: Researches on the effects of the El Niño Southern Oscillation (ENSO) over precipitation and temperature, such as drought, flood, and anomalous high or cold temperatures, have large importance because of the impacts on the environment, society, and economy. Some recent studies, focusing on the Northern Hemisphere, have indicated that the basic response of ENSO is dependent on the phase of the Madden-Julian Oscillation (MJO). The present work investigates the combined response of the phases of these two distinct phenomena, ENSO and MJO, over South America. Our goal is to explore the relative importance of the MJO to precipitation and temperature anomalies during each ENSO phase. A composite analysis with each combination of the phases of ENSO and MJO was performed to obtain the mean patterns of temperature and precipitation over South America for the months of November to March (austral summer) and May to September (austral winter). The results showed that the precipitation and temperature anomaly patterns observed during the ENSO phases, without the concurrent occurrence of the MJO, can be strengthened or weakened during events where ENSO and MJO occur simultaneously. Moreover, the effect on the anomaly patterns in these events depends on the MJO phase. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    Publication Date: 2016-03-29
    Description: The projection skills of five ensemble methods were analyzed according to simulation skills, training period, and ensemble members, using 198 sets of pseudo-simulation data (PSD) produced by random number generation assuming the simulated temperature of regional climate models. The PSD sets were classified into 18 categories according to the relative magnitude of bias, variance ratio, and correlation coefficient, where each category had 11 sets (including 1 truth set) with 50 samples. The ensemble methods used were as follows: equal weighted averaging without bias correction (EWANBC), EWA with bias correction (EWAWBC), weighted ensemble averaging based on root mean square errors and correlation (WEARAC), WEA based on the Taylor score (WEATay), and multivariate linear regression (MulReg). The projection skills of the ensemble methods improved generally as compared with the best member for each category. However, their projection skills are significantly affected by the simulation skills of the ensemble member. The weighted ensemble methods showed better projection skills than non-weighted methods, in particular, for the PSD categories having systematic biases and various correlation coefficients. The EWANBC showed considerably lower projection skills than the other methods, in particular, for the PSD categories with systematic biases. Although MulReg showed relatively good skills, it showed strong sensitivity to the PSD categories, training periods, and number of members. On the other hand, the WEATay and WEARAC showed relatively superior skills in both the accuracy and reliability for all the sensitivity experiments. This indicates that WEATay and WEARAC are applicable even for simulation data with systematic biases, a short training period, and a small number of ensemble members. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Publication Date: 2016-04-01
    Description: The multiple downscaled scenario products allow us to assess the uncertainty of the variations of precipitation and temperature in the current and future periods. Probabilistic assessments of both climatic variables help better understand the interdependence of the two and thus, in turn, help in assessing the future with confidence. In the present study, we use ensemble of statistically downscaled precipitation and temperature from various models. The dataset used is multi-model ensemble of 10 global climate models (GCMs) downscaled product from CMIP5 daily dataset using the Bias Correction and Spatial Downscaling (BCSD) technique, generated at Portland State University. The multi-model ensemble of both precipitation and temperature is evaluated for dry and wet periods for 10 sub-basins across Columbia River Basin (CRB). Thereafter, copula is applied to establish the joint distribution of two variables on multi-model ensemble data. The joint distribution is then used to estimate the change in trends of said variables in future, along with estimation of the probabilities of the given change. The joint distribution trends vary, but certainly positive, for dry and wet periods in sub-basins of CRB. Dry season, generally, is indicating a higher positive change in precipitation than temperature (as compared to historical) across sub-basins with wet season inferring otherwise. Probabilities of changes in future, as estimated from the joint distribution, indicate varied degrees and forms during dry season whereas the wet season is rather constant across all the sub-basins. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    Publication Date: 2016-03-31
    Description: Variation of soil moisture during active and weak phases of summer monsoon JJAS (June, July, August, and September) is very important for sustenance of the crop and subsequent crop yield. As in situ observations of soil moisture are few or not available, researchers use data derived from remote sensing satellites or global reanalysis. This study documents the intercomparison of soil moisture from remotely sensed and reanalyses during dry spells within monsoon seasons in central India and central Myanmar. Soil moisture data from the European Space Agency (ESA)—Climate Change Initiative (CCI) has been treated as observed data and was compared against soil moisture data from the ECMWF reanalysis-Interim (ERA-I) and the climate forecast system reanalysis (CFSR) for the period of 2002–2011. The ESA soil moisture correlates rather well with observed gridded rainfall. The ESA data indicates that soil moisture increases over India from west to east and from north to south during monsoon season. The ERA-I overestimates the soil moisture over India, while the CFSR soil moisture agrees well with the remotely sensed observation (ESA). Over Myanmar, both the reanalysis overestimate soil moisture values and the ERA-I soil moisture does not show much variability from year to year. Day-to-day variations of soil moisture in central India and central Myanmar during weak monsoon conditions indicate that, because of the rainfall deficiency, the observed (ESA) and the CFSR soil moisture values are reduced up to 0.1 m3/m3 compared to climatological values of more than 0.35 m3/m3. This reduction is not seen in the ERA-I data. Therefore, soil moisture from the CFSR is closer to the ESA observed soil moisture than that from the ERA-I during weak phases of monsoon in the study region. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    Publication Date: 2016-04-01
    Description: Enterprising endeavour has been taken in this work to realize and estimate the persistence in memory of the daily mean dew point time series obtained from seven different weather stations viz. Kolkata, Chennai (Madras), New Delhi, Mumbai (Bombay), Bhopal, Agartala and Ahmedabad representing different geographical zones in India. Hurst exponent values reveal an anti-persistent behaviour of these dew point series. To affirm the Hurst exponent values, five different scaling methods have been used and the corresponding results are compared to synthesize a finer and reliable conclusion out of it. The present analysis also bespeaks that the variation in daily mean dew point is governed by a non-stationary process with stationary increments. The delay vector variance (DVV) method has been exploited to investigate nonlinearity, and the present calculation confirms the presence of deterministic nonlinear profile in the daily mean dew point time series of the seven stations. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    Publication Date: 2016-04-01
    Description: Urban street trees provide many environmental, social, and economic benefits for our cities. This research explored the role of street trees in Melbourne, Australia, in cooling the urban microclimate and improving human thermal comfort (HTC). Three east–west (E–W) oriented streets were studied in two contrasting street canyon forms (deep and shallow) and between contrasting tree canopy covers (high and low). These streets were instrumented with multiple microclimate monitoring stations to continuously measure air temperature, humidity, solar radiation, wind speed and mean radiant temperature so as to calculate the Universal Thermal Climate Index (UTCI) from May 2011 to June 2013, focusing on summertime conditions and heat events. Street trees supported average daytime cooling during heat events in the shallow canyon by around 0.2 to 0.6 °C and up to 0.9 °C during mid-morning (9:00–10:00). Maximum daytime cooling reached 1.5 °C in the shallow canyon. The influence of street tree canopies in the deep canyon was masked by the shading effect of the tall buildings. Trees were very effective at reducing daytime UTCI in summer largely through a reduction in mean radiant temperature from shade, lowering thermal stress from very strong (UTCI 〉 38 °C) down to strong (UTCI 〉 32 °C). The influence of street trees on canyon air temperature and HTC was highly localized and variable, depending on tree cover, geometry, and prevailing meteorological conditions. The cooling benefit of street tree canopies increases as street canyon geometry shallows and broadens. This should be recognized in the strategic placement, density of planting, and species selection of street trees. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Publication Date: 2016-04-01
    Description: On the basis of the daily minimum ( T min), mean ( T mean), and maximum ( T max) temperature records of 25 meteorological stations in Northeast China (NEC) and 10 weather stations in Hokkaido, Japan (HKD), from 1951 to 2011, we comparatively analyzed the change in extreme temperature events and the relationship of these events with the mean value. Results showed that for the extreme lowest temperature (ELT) frequency, approximately 96 % of the stations exhibited decreasing trends ranging from −0.63 to 0 days/decade in NEC, whereas all the stations in HKD showed decreasing trends ranging from −0.4 to 0 days/decade. However, the average decrease in amplitude of 0.24 days/decade in HKD was significantly less than the 0.27 days/decade average in NEC. The extreme highest temperature (EHT) frequency trends in the two regions showed insignificant increases. Notable decreasing trends for the ELT intensity were found at −0.9 to 0 %/decade in 92 % of the stations in NEC and −1.1 to 0 %/decade in 90 % of the stations in HKD. Inversely, increasing trends in EHT intensity were observed in 80 % of the stations over HKD, ranging from 0.06 to 0.32 %/decade, and the majority of the stations (64 %) showed increasing trends in NEC. T mean and T min had strong negative correlations with the ELT intensity in NEC, whereas T mean and T min had strong significant negative correlations with the ELT frequency in HKD. T min, T mean, and T max between NEC and HKD exhibited strong significant positive correlations. The frequency and intensity of the ELT in both regions showed significant positive correlations. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    Publication Date: 2016-03-29
    Description: Potential changes in future climate in the Texas Plains region were investigated in the context of agriculture by analyzing three climate model projections under the A2 climate scenario (medium–high emission scenario). Spatially downscaled historic (1971–2000) and future (2041–2070) climate datasets (rainfall and temperature) were downloaded from the North American Regional Climate Change Assessment Program (NARCCAP). Climate variables predicted by three regional climate models (RCMs) namely the Regional Climate Model Version3–Geophysical Fluid Dynamics Laboratory (RCM3-GFDL), Regional Climate Model Version3–Third Generation Coupled Global Climate Model (RCM3-CGCM3), and Canadian Regional Climate Model–Community Climate System Model (CRCM-CCSM) were evaluated in this study. Gaussian and Gamma distribution mapping techniques were employed to remove the bias in temperature and rainfall data, respectively. Both the minimum and maximum temperatures across the study region in the future showed an upward trend, with the temperatures increasing in the range of 1.9 to 2.9 °C and 2.0 to 3.2 °C, respectively. All three climate models predicted a decline in rainfall within a range of 30 to 127 mm in majority of counties across the study region. In addition, they predicted an increase in the intensity of extreme rainfall events in the future. The frost-free season as predicted by the three models showed an increase by 2.6–3.4 weeks across the region, and the number of frost days declined by 17.9 to 30 %. Overall, these projections indicate considerable changes to the climate in the Texas Plains region in the future, and these changes could potentially impact agriculture in this region. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    Publication Date: 2016-03-17
    Description: We examined the changes in streamflow on the northern slopes of the Tianshan Mountains in northern Xinjiang, China, over two time scales: the past 500 years, based on dendrochronology data; and the past 50 years, based on streamflow data from hydrological stations. The method of artificial neural networks built from the data of the 50-year period was used to reconstruct the streamflow of the 500-year period. The results indicate that streamflow has undergone seven high-flow periods and four low-flow periods during the past 500 years. To identify possible transition points in the streamflow, we applied the Mann–Kendall and running T tests to the 50- and 500-year periods, respectively. During the past 500 years, streamflow has changed significantly from low to high flow about three to four times, and from high to low flow about three to five times. Over the recent 50 years, there have been three phases of variation in river runoff, and the most distinct transition of streamflow occurred in 1996. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    Publication Date: 2016-03-15
    Description: In this paper, we attempt to highlight the relevance of cutoff low systems (CoLs) to large-scale heavy precipitation events within the Alpine region which often lead to catastrophic flooding. The main results of this study are (1) a detailed climatology (1971–1999) of CoLs for the European region, (2) contribution of CoLs to extreme precipitation events in the European Alpine region, (3) identification of regions within the European Alps most affected by extreme precipitation caused by CoLs, and (4) identification of regions where presence of CoLs is related to extreme precipitation in the Alpine region. The findings of this paper suggest that CoLs have a significant correlation with extreme precipitation events and strongly influence the climate of the Alpine region. The total contribution of CoLs to large-scale heavy precipitation events ranges between 20 and 95 % and is most pronounced in the northern and eastern parts of the Alps. More than 80 % of the events occur in the summer season. The area around the Alps and West of Spain (over the Atlantic Ocean) is the most affected region. The location of the center of CoLs that affect the Alpine region most occur on the northern and southern sides of the Alpine ridge. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    Publication Date: 2016-03-21
    Description: Accurate temporal corrections for the spatial meteorological parameters obtained through mobile measurements are essential in the synchronous analysis of local urban climates. This paper discusses current temporal correction models and proposes an improved model by considering correlation coefficients that are influenced by the underlying surface conditions, and the distance between the stationary weather stations and the mobile location points during a mobile measurement. Together with four adjacent, simultaneously recording stationary weather stations, long-term mobile temperature and humidity measurements were taken along a 17-km transect covering 18 mobile location points through the University Town of Shenzhen. Using the multiple air temperature and relative humidity values of the mobile location points and stationary weather stations, the function equations for determining the correlation coefficients were obtained for application in the proposed temporal correction model. Further, three kinds of validation methods were applied to compare temporal correction models. Validation results showed that the temporal correction model proposed in this study was significantly more accurate and reliable compared to the other models. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Publication Date: 2016-03-12
    Description: Two enhanced temperature-index (T-index) models are proposed by incorporating meteorological parameters viz. relative humidity, wind speed and net radiation. The models are an attempt to explore different climatic variables other than temperature affecting glacier surface melting. Weather data were recorded at Chorabari Glacier using an automatic weather station during the summers of 2010 (July 10 to September 10) and 2012 (June 10 to October 25). The modelled surface melt is validated against the measured point surface melting at the snout. Performance of the developed models is evaluated by comparing with basic temperature-index model and is quantified through different efficiency criteria. The results suggest that proposed models yield considerable improvement in surface melt simulation . Consequently, the study reveals that glacier surface melt depends not only on temperature but also on weather parameters viz. relative humidity, wind speed and net radiation play a significant role in glacier surface melting. This approach provides a major improvement on basic temperature-index method and offers an alternative to energy balance model. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    Publication Date: 2016-03-08
    Description: The North Atlantic Oscillation (NAO) has significant effects on sea levels, weather, and climate. In this study, the sea level trends and the effects of the North Atlantic Oscillation Indices (NAOI) on annual mean sea level data were assessed for the Black Sea and the Eastern Mediterranean Sea. The trends of sea level and NAOI were determined using Mann-Kendall dimensionless z statistics. Generally, upward sea level trends were detected for the Black Sea and the Eastern Mediterranean Sea. In the Black Sea, significant and continuous upward trends were detected after the year 1950. Weaker trends were detected for the Eastern part of the Mediterranean Sea. Sea level trends were correlated with trends in NAO indices; negative correlations were detected for the Black Sea, whereas positive correlations were found for the Eastern Mediterranean Sea. Paired t tests were performed to determine the turning points for all sea level data sets. The value of t was positive for all data sets, which means that the mean value of the data set before the turning point was smaller than the mean value of the data set after the turning point. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    Publication Date: 2016-01-01
    Description: Observational evidence of the impacts of land use/land cover change (LULCC) on changes in surface solar radiation (SSR) in eastern China (EC) during 1979–2008 are identified by using diurnal temperature range as a proxy of SSR and by using observation minus reanalysis approach to disentangle these effects. For the period 1979–2008, the impact of LULCC is shown as a reduction in SSR in most stations in EC, whereas SSR in the reanalysis data has increased at nearly every location. The competition of the dimming effect of LULCC with the brightening effect in the reanalysis results in an observed dipole pattern of SSR with slightly decreasing (increasing) trends in most stations north (south) of the Yangtze River and statistically significant decreasing trends in central EC. In terms of EC area mean, this competition has resulted in a slightly dimming trend in the observed SSR during 1979–2008, although a transition from an apparent dimming to a general leveling off near 1990 is identified. For the period 1990–2008, LULCC has significantly reduced SSR in central EC and southern China. This dimming effect of LULCC competes with the apparent brightening effect in the reanalysis to result in the general leveling off in the observed SSR in terms of EC area mean and a sandwich spatial pattern in the observed SSR in EC where parts of central EC show significant dimming. The impact of LULCC on the changes in SSR may be through both biogeophysical and biogeochemical processes. ©2014 The Author(s)〈br /〉〈br /〉〈a href="http://doi.org/10.1007/s00704-014-1334-5" target="_blank"〉〈img src="http://bib.telegrafenberg.de/typo3temp/pics/f2f773b55e.png" border="0"〉〈/a〉
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    Publication Date: 2016-01-01
    Description: This study aims at quantifying the trends in mean temperatures and aridity index over Rwanda for the period of 1961–1992, based on analysis of climatic data (temperatures, precipitations, and potential evapotranspiration). The analysis of magnitude and significance of trends in temperatures and aridity index show the degree of climate change and mark the level of vulnerability to extreme events (e.g., droughts) in different areas of the country. The study reveals that mean temperatures increased in most parts of the country, with a significant increase observed in the eastern lowlands and in the southwestern parts. The highlands located in the northwest and the Congo-Nile crest showed a nonsignificant increase in mean temperatures. Aridity index increased only in March, April, October, and November, corresponding with the rainy seasons. The remaining months of the year showed a decreasing trend. At an annual resolution, the highlands and the western region showed a rise in aridity index with a decreasing pattern over the eastern lowlands and the central plateau. Generally, the highlands presented a nonsignificant increase in mean temperatures and aridity index especially during the rainy seasons. The eastern lowlands showed a significant increase in mean temperatures and decreasing trends in aridity index. Therefore, these areas are bound to experience more droughts, leading to reduced water and consequent decline in agricultural production. On the other hand, the north highlands and southwest region will continue to be more productive. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Publication Date: 2016-01-01
    Description: Although climate is recognised as one of the main drivers of viticulture success, its main features have not been sufficiently described in many viticultural regions, including Extremadura, which contains one of the largest grapevine-growing areas in Europe. Using climatic data from 80 weather stations located throughout Extremadura, seven bioclimatic indices were calculated to estimate heat accumulation and potential water balance during the growing season and the thermal regime during the ripening of grapes. Differences in some climatic indices were found, and after a multivariate geographic analysis, four groups were delimited containing weather stations with similar climatic features, with variability between groups explained by heat accumulation and tempearture and thermal amplitude during the ripening season. Suitability for cultivation of grapevines without thermal restriction and temperate nights during the ripening period are the main characteristics of the weather stations studied, but spatial variability found in climatic potential denotes the importance of differentiating locations to properly relate the viticultural climate to grape quality factors and the style of wines produced. The climatic features of the four groups are very similar to those described in other viticultural regions, including those in close proximity to Extremadura and others worldwide, but few studies have used broad and updated temporal climate data for computing bioclimatic indices as in this case study. Finally, trends in climate indices were analysed. Results revealed that all groups have experienced warmer growing seasons, driven mainly by changes in minimum temperatures. This fact has numerous potential impacts, including changes in grapevine phenological timing, disruption of balanced composition in grapes (ultimately affecting wine characteristics), alterations in varieties grown and spatial changes in viable winegrape-growing zones. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    Publication Date: 2016-01-01
    Description: A spatial analysis of partial duration series, PDS, of the dry spell lengths, DSL, is applied to 267 European stations during years 1951–2000. A DSL is defined as the number of consecutive days with precipitation below 0.1 mm/day. For every station, PDS are made of DSL longer than those corresponding to 95th empirical percentile. The L-skewness and L-kurtosis diagram of the PDS distributions shows that most of the stations fit well a generalised Pareto, GP, model. Only four rain gauge records at the southeast Mediterranean coast notably depart from this model. In addition, DSL maps for return periods of 2, 5, 10, 25 and 50 years are introduced by taking into account GP parameters, which are estimated by fitting the GP distribution to empirical PDS distributions of DSL. A comparative study with those obtained in a previous paper, for the whole DSL series and the corresponding best distribution model (Pearson type III), shows that the differences of DSL for the different return periods keep within ±10 % in most of rain gauges. Moreover, a principal component analysis, PCA, is applied to the four first L-moments of the 267 rain gauges. Then, a regionalization in 11 groups is obtained after the clustering process. Finally, a regional frequency analysis is attempted, being possible to assign a GP parent distribution with different parameters to 7 out of the 11 groups. ©2014 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    Publication Date: 2016-01-01
    Description: The Simple Biosphere Model (SiB2) and the 2 × 2 km resolution National Land use/Land Cover database were used to investigate the effects of Land Use/Cover Change (LUCC) on land surface energy balance and climate in Jilin Province, northeast China, from 1990 to 2005. The spatial patterns of the components of surface energy balance (i.e., net radiation ( R n), latent heat (LH), sensible heat (SH), and albedo ( α )) and climate (i.e., canopy temperature ( T c), diurnal temperature range (DTR)), as well as the roles of land cover type in variations of energy balance and climate, were investigated. The results showed that there were general similar trends in R n, LH, SH, and α in the LUCC process. The spatial patterns of T c and DTR also showed consistent relationships with LUCC processes. Leaf area index (LAI) and canopy conductance ( g c) were found to be the key factors in controlling the spatial patterns of the components of surface energy balance and T c. Using linear correlation method, the gaps of the components of surface energy balance were well-explained by the differences of LAI and g c, and R n had a better correlation with T c and DTR, in the process of LUCC. The surface energy partitioning of R n into LH and SH could not only dampen or strengthen the temperature difference, but also change the relative size of albedo-based R n when the albedo gap was small, between land cover types. ©2014 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    Publication Date: 2016-01-01
    Description: Understanding vegetation dynamics provides information on changes in land cover that can directly be related to regional changes in the climate system. In data-sparse regions, i.e. northwest Morocco studies are limited by the availability of comprehensive information on precipitation. We extracted precipitation data of high spatiotemporal resolution (2 km, 1 day) from the Northwest Africa Reanalysis (NwAR) and gridded Normalized Difference Negetation Index (NDVI) of the Moderate Resolution Imaging Spectroradiometer (MODIS) that cover northwest Morocco over ten hydrological years (September 2000 to August 2010). The results are based on a sequence of linear regression analyses. The mean precipitation of different input timeframes is systematically applied as the predicting variables to the mean NDVI of the growing seasons. Results show that 73 % of the variance in mean NDVI is explained by the variance in mean precipitation at the beginning of the growing season (November to the end of December). The results also show that 75 % of the variance in the mean NDVI of agriculturally used areas is explained by the variance in mean precipitation of beginning September to the end of December. Potentially irrigated land cover of low to medium explained variance but of a high seasonal range in NDVI cover about 14 % of the study region. We conclude that a considerable part of agricultural used areas are still potentially rain-fed. The applied methods and especially the re-analysed precipitation data of high spatiotemporal resolution open a new quality of analysis valuable for, e.g. monitoring aspects, policy decisions or regulatory actions. ©2014 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    Publication Date: 2016-01-01
    Description: The climatic evolution of the Bani river watershed, the main tributary to the upper Niger River, is approached through the spatiotemporal variability of rainfall grids over the 1950–2006 period. The analyses are conducted, and their results compared, using four different methods of spatial interpolation of rainfall fields: the spline, kriging, weighted inverse distance, and nearest neighbor methods. The largest changes are observed for all of these grids, but differences—and in some cases divergent results—appear in the details. The analysis shows a substantial decline in rainfall, particularly marked in the center of the basin, during the 1970–2000 period with respect to the 1950–1969 period, and a slight upturn in the northern part, mainly since the beginning of the 1990s. The rainfall deficit can be attributed to a combination of factors: an earlier and drier end of the rainy season, less precipitation in the middle of the rainy season, more dry days and lower amounts of precipitation on rainy days. Two drought indices—the Effective Drought Index and Standardized Precipitation Index—revealed that the maximum duration of drought events increased most in the central part of the basin. Lastly, to supplement this comparison of methods of spatial interpolation of rainfall fields, the sensitivity of a hydrological model (GR2M) to rainfall data was tested. Given the distribution and density of rain gauge stations available in the Bani watershed, the kriging method is found to yield the best hydrological modeling performance. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Publication Date: 2016-01-01
    Description: The study presents a precipitation intercomparison based on two satellite-derived datasets (TRMM 3B42, CMORPH), four raingauge-based datasets (GPCC, E-OBS, Willmott & Matsuura, CRU), ERA Interim reanalysis (ERAInt), and a single climate simulation using the WRF model. The comparison was performed for a domain encompassing parts of Europe and the North Atlantic over the 11-year period of 2000–2010. The four raingauge-based datasets are similar to the TRMM dataset with biases over Europe ranging from –7 % to +4 %. The spread among the raingauge-based datasets is relatively small over most of Europe, although areas with greater uncertainty (more than 30 %) exist, especially near the Alps and other mountainous regions. There are distinct differences between the datasets over the European land area and the Atlantic Ocean in comparison to the TRMM dataset. ERAInt has a small dry bias over the land; the WRF simulation has a large wet bias (+30 %), whereas CMORPH is characterized by a large and spatially consistent dry bias (–21 %). Over the ocean, both ERAInt and CMORPH have a small wet bias (+8 %) while the wet bias in WRF is significantly larger (+47 %). ERAInt has the highest frequency of low-intensity precipitation while the frequency of high-intensity precipitation is the lowest due to its lower native resolution. Both satellite-derived datasets have more low-intensity precipitation over the ocean than over the land, while the frequency of higher-intensity precipitation is similar or larger over the land. This result is likely related to orography, which triggers more intense convective precipitation, while the Atlantic Ocean is characterized by more homogenous large-scale precipitation systems which are associated with larger areas of lower intensity precipitation. However, this is not observed in ERAInt and WRF, indicating the insufficient representation of convective processes in the models. Finally, the Fraction Skill Score confirmed that both models perform better over the Atlantic Ocean with ERAInt outperforming the WRF at low thresholds and WRF outperforming ERAInt at higher thresholds. The diurnal cycle is simulated better in the WRF simulation than in ERAInt, although WRF could not reproduce well the amplitude of the diurnal cycle. While the evaluation of the WRF model confirms earlier findings related to the model’s wet bias over European land, the applied satellite-derived precipitation datasets revealed differences between the land and ocean areas along with uncertainties in the observation datasets. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    Publication Date: 2016-03-17
    Description: Long-term variability of El Niño (EN) cycle has been the topic of several studies, mainly because of its impacts on climate around the globe. This variability has been mainly described by changes in the intensity and frequency of EN events. In this study, interdecadal changes in the zonal evolution of EN-related sea surface temperature anomalies (SSTA) and their possible link with a well-known mode of Pacific interdecadal variability are analyzed. EN events are classified according to the sense of zonal propagation of SSTA along the equatorial Pacific during the period 1900–2012. As a result, two types of EN are defined: eastward-directed and westward-directed EN. It is found that EN-related SSTA preferably evolves to the east (west) during the warm (cold) phase of the Pacific Decadal Oscillation. Hence, this study offers new insights into the possible causes of long-term EN changes. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Publication Date: 2016-03-01
    Description: Due to the substantial decrease of water resources as well as the increase in demand and climate change phenomenon, analyzing the trend of hydrological parameters is of paramount importance. In the present study, investigations were carried out to identify the trends in streamflow at 20 hydrometric stations and 11 rainfall gauging stations located in Karkheh River Basin (KRB), Iran, in monthly, seasonal, and annual time scales during the last 38 years from 1974 to 2011. This study has been conducted using two versions of Mann–Kendall tests, including (i) Mann–Kendall test by considering all the significant autocorrelation structure (MK3) and (ii) Mann–Kendall test by considering LTP and Hurst coefficient (MK4). The results indicate that the KRB streamflow trend (using both test versions) has decreased in all three time scales. There is a significant decreasing trend in 78 and 73 % of the monthly cases using the MK3 and MK4 tests, respectively, while these percentages changed to 80 and 70 % on seasonal and annual time scales, respectively. Investigation of the trend line slope using Theil–Sen’s estimator showed a negative trend in all three time scales. The use of MK4 test instead of the MK3 test has caused a decrease in the significance level of Mann–Kendall Z -statistic values. The results of the precipitation trends indicate both increasing and decreasing trends. Also, the correlation between the area average streamflow and precipitation shows a strong correlation in annual time scale in the KRB. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    Publication Date: 2016-03-01
    Description: Prior to hydrological assessment of climate change at catchment scale, an applied methodology is necessary to evaluate the performance of climate models available for a given catchment. This study presents a grid-based performance evaluation approach as well as an intercomparison framework to evaluate the uncertainty of climate models for rainfall reproduction. For this purpose, we used outputs of two general circulation models (GCMs), namely ECHAM5 and CCSM3, downscaled by a regional climate model (RCM), namely RegCM3, over ten small to mid-size catchments in Rize Province, Turkey. To this end, five rainfall-borne climatic statistics are computed from the outputs of ECHAM5-RegCM3 and CCSM3-RegCM3 combinations in order to compare with those of observations in the province for the reference period 1961–1990. Performance of each combination is tested by means of scatter diagram, bias, mean absolute bias, root mean squared error, and model performance index (MPI) measures. Our results indicated that ECHAM5-RegCM3 overestimates the total monthly rainfall observations whereas CCSM3-RegCM3 tends to underestimate. In terms of maximum monthly and annual maximum rainfall reproduction, ECHAM5-RegCM3 shows higher performance than CCSM3-RegCM3, particularly in the coastland areas. In contrast, CCSM3-RegCM3 outperforms ECHAM5-RegCM3 in reproducing the number of rainy days, especially in the inland areas. The results also revealed that if a GCM-RCM combination performs well for a portion (statistic) of a catchment, it is not necessarily appropriate for the other portions (statistics). Moreover, the MPI measure demonstrated the superiority of ECHAM5-RegCM3 to CCSM3-RegCM3 up to 33 % excelling for annual rainfall reproduction in Rize Province. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    Publication Date: 2016-02-18
    Description: The full surface energy balance of the sea water of the Arctic fjord was analysed for the period from May to November 2014 in Hornsund (SW Spitsbergen). The sensible and latent turbulent fluxes were measured with the aid of the open-path eddy covariance method. The measurement site was located in the Wilczek Peninsula (Wilczekodden) on the rocks, right at the seafront. At this location, and with the wind system observed there, the source area of turbulent fluxes was spread over the sea water of the Hornsundfjord. The turbulent fluxes were calculated for 1-h intervals with a standard methodology. Stationarity was checked by three independent tests, and two datasets were analysed independently: data approved by all three tests, and data approved by at least one of the tests. The sensible heat flux, Q H , undergoes a clear seasonal regularity, with downward heat transport (negative fluxes) from July to September (with mean ranges from −30 to −15 Wm−2), reaching close to zero in October, then upward in the other months of the analysed period, reaching maximum in November (50 Wm−2). The latent heat flux, Q E , was mostly positive (more than 90 %) and more intensive. The highest mean values of Q E were recorded in July and November (around 135 Wm−2), with the lowest in May, June and August (around 70 Wm−2). Very intensive latent heat fluxes, above 200 Wm−2, in extreme cases exceeding 500 Wm−2, were observed in all months. ©2016 The Author(s)〈br /〉〈br /〉〈a href="http://doi.org/10.1007/s00704-016-1756-3" target="_blank"〉〈img src="http://bib.telegrafenberg.de/typo3temp/pics/f2f773b55e.png" border="0"〉〈/a〉
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Publication Date: 2016-02-13
    Description: The statistical change-point analysis demonstrates that there is a climate regime shift in the April mean precipitation in Korea in 1981. The April mean precipitation in the years post-1981 showed a distinct decrease compared to the years pre-1981. This phenomenon was also noticed in China and Japan, excluding south China. One of the major causes for this decrease in April mean precipitation was the increased snow depth in the mid-latitude regions of continental East Asia. This resulted in a strengthened cold and dry anticyclone anomaly over continental East Asia and a relatively weakened subtropical anticyclone anomaly over the western North Pacific, thus forcing a continuation of the typical winter pressure pattern of “high-West and low-East” in East Asia in April. The strengthened northerly anomaly from this zonal pressure pattern anomaly played a significant role in restricting the northern movement of the subtropical anticyclone and preventing the inflow of warm and humid air into Korea. ©2016 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Publication Date: 2016-01-01
    Description: Based on the observed data during the period from 1958 to 2012 in Xinjiang, China, we investigated the temporal and spatial complexity of precipitation distribution by using an integrative approach combining the phase space reconstruction (PSR), correlation dimension (CD), variogram, and cokriging interpolation. The CD values showed that the precipitation dynamic is a complex and chaotic system, and its complexity decreases along with the increase of temporal scale. To describe the precipitation dynamics, it needs at least four independent variables at daily scale, and at least three independent variables at monthly scale, whereas at least two independent variables are needed at seasonal and annual scales. The spatial variation of CD value at daily and monthly scales is described by the exponential variogram model, whereas that at seasonal and annual scale needs to be respectively described by the spherical and Gaussian variogram model. The higher CD values mainly distribute on complex landform such as mountain areas, whereas the lower CD values mainly distribute on the flat landform such as basin area, which indicate that the spatial complexity of precipitation distribution is derived from the complex landform. ©2015 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Publication Date: 2016-01-01
    Description: Wind is the power behind many erosion processes and is responsible for many of the characteristics of arid zone geomorphology. Wind velocity is a key factor in determining the potential sand transport, but the nature of the wind velocity data can strongly affect assessments of the risk of blowing sand. In this study, we obtained real-time wind velocity data in a region of the Tengger Desert with shifting sands, in the Badain Jaran Desert, and in the Madoi desertification land, with the data obtained at 1-min intervals, and used the data to determine the influence of how the wind velocity was calculated (mean versus mid-point values and the averaging time used to calculate these values) on sand drift potential. In the three regions, for both the mean and the mid-point wind velocities, the estimated drift potential decreased with increasing averaging time. The relationships between velocities calculated using the different averaging time intervals and the value calculated using a 1-min interval could be expressed as linear functions. The drift potential calculated using the mid-point wind velocity was larger than that calculated using the mean wind velocity. ©2014 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Publication Date: 2016-01-01
    Description: Heat island is the main product of urban climate, and one of the important problems of twenty-first century. Cities in tropical countries suffer extensively due to the urban heat island effect, and urban climate studies are necessary to improve the comfort level and city planning. Chennai is the tropical city; it is the fourth largest metropolis in India and one of the fastest growing economic and industrial growth centers in South Asia. The spatial distribution of heat intensity in Chennai Metropolitan Area was studied, and the influence of land use and green cover were analyzed in the present work. Mobile measurements were carried out throughout the study area using a grid network to represent various land use patterns of the city. The study revealed some heat and cool pockets within the city limit; the maximum intensities of temperature were noticed in the central core city and north Chennai, which are distinguished for their commercial centers and densely populated residential areas. In morning time, temperature differences between fringes and central parts of heat packets were in the range of 3–4.5 °C. Land use and green cover play a critical role in microclimate and influences it. Green cover has a significant negative correlation with observed microclimate variations. Thus, the study urges city administration, policy makers, and architects to take up effective mitigation and adaptation strategies in the city to make people more comfortable. ©2014 Springer-Verlag Wien
    Print ISSN: 0177-798X
    Electronic ISSN: 1434-4483
    Topics: Geosciences , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    Publication Date: 2016-01-01
    Description: Monthly means of ground-based GPS measurements of precipitable water vapor (PWV) from six stations in the USA covering the period January 2007–December 2012 are analyzed to investigate their usefulness for monitoring meteorological wet/dry spells. For this purpose, the relationship between PWV and the Standardized Precipitation Index (SPI) on 1-month timescale is investigated. The SPI time series at grid points close to the stations are computed using gridded precipitation records from the NOAA Climate Prediction Center (CPC) unified precipitation dataset (January 1948–April 2012). GPS measurements are first verified against PWV data taken from the latest ECMWF reanalysis ERA-Interim; these PWV reanalysis data, which extend back to 1979, are then used jointly with CPC precipitation to compute precipitation efficiency (PE), defined as the pe