ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Publication Date: 2011-08-24
    Description: The Lightning Imaging Sensor (LIS) wide field-of-view solid-state camera can measure the global distribution of lightning from LEO, through the use of a narrowband interference filter to detect the neutral O band at 777.4 nm. Prelaunch testing and calibration of the LIS has required three separate laboratory systems; absolute radiometric calibration of the sensor will be furnished over the whole spectral range by a high resolution monochromator and motorized gimbals.
    Keywords: SPACECRAFT INSTRUMENTATION
    Type: In: Instrumentation for planetary and terrestrial atmospheric remote sensing; Proceedings of the Meeting, San Diego, CA, July 23, 24, 1992 (A93-27076 09-35); p. 217-226.
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2004-12-03
    Description: The Lightning Imaging Sensor (LIS) is a NASA Earth Observing System (EOS) instrument on the Tropical Rainfall Measuring Mission (TRMM) platform designed to acquire and investigate the distribution and variability of total lightning (i.e., cloud-to-ground and intracloud) between q35' in latitude. Since lightning is one of the responses of the atmosphere to thermodynamic and dynamic forcing, the LIS data is being used to detect deep convection without land-ocean bias, estimate the precipitation mass in the mixed phased region of thunderclouds, and differentiate storms with strong updrafts from those with weak vertical motion.
    Keywords: Meteorology and Climatology
    Type: 11th International Conference on Atmospheric Electricity; 746-749; NASA/CP-1999-209261
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2004-12-03
    Description: The Optical Transient Detector (OTD) is a space-based instrument specifically designed to detect and locate lightning discharges (intracloud and cloud-to-ground) as it orbits the Earth. A statistical examination of OTD lightning data reveals that nearly 1.2 billion flashes occurred over the entire earth during the one year period from September 1995 through August 1996. This translates to an average of 37 lightning flashes occurring around the globe every second, which is well below the traditional estimate of 100 flashes per second. An average of 75% of the global lightning activity during the year occurs between 30' S and 30' N. An analysis of the annual lightning distribution reveals that an average of 82% of the lightning flashes occur over the continents and 18% over the oceans, which translates to an average land-ocean flash density ratio of nearly 11.
    Keywords: Meteorology and Climatology
    Type: 11th International Conference on Atmospheric Electricity; 726-729; NASA/CP-1999-209261
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2004-12-03
    Description: The lightning frequency model developed by Baker, Christian and Latham (1995) has been refined and extended, in an effort to provide a more realistic framework from which to examine computationally the relationships that might exist between lightning frequency f (which is now being routinely measured from satellites, using NASA/MSFC devices) and a variety of cloud physical parameters, including precipitation rate, updraught speed and non-precipitating ice content. Model results indicate the existence of a simple relationship between lightning frequency f and the upward flux of ice crystals into the thunderstorm anvil. It follows that, for a particular situation, one can assign a specific mass of non-precipitating ice to an individual lightning stroke. Therefore it may prove possible - using satellite measurements of global lightning - to estimate the atmospheric loading of ice crystals in thunderstorm anvils: a parameter of climatological importance. Early results from this work are presented, together with further studies of the relationships between f and other thundercloud parameters.
    Keywords: Meteorology and Climatology
    Type: 11th International Conference on Atmospheric Electricity; 363-366; NASA/CP-1999-209261
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2004-12-03
    Description: Since April 1995, lightning activity around the globe has been monitored with the Optical Transient Detector (OTD). The OTD observations acquired during the one year period from September 1995 through August 1996 have been used to statistically determine the number of flashes that occur over the Earth during each hour of the diurnal cycle, expressed both as a function of local time and universal time. The globally averaged local [il,htnina activity displays a peak in late afternoon (1500-1800 local time) and a minimum in the morning hours (0600- 1000 local time) consistent with convection associated with diurnal heating. No diurnal variation is found for oceanic storms. The diurnal lightning distribution (universal time) for the globe displays a variation of about 35% about its mean as compared to the Carnegie curve which has a variation of only 15% above and below the mean.
    Keywords: Meteorology and Climatology
    Type: 11th International Conference on Atmospheric Electricity; 742-745; NASA/CP-1999-209261
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2011-08-24
    Description: An aircraft locally distorts the ambient thundercloud electric field. In order to determine the field in the absence of the aircraft, an aircraft calibration is required. In this work a matrix inversion method is introduced for calibrating an aircraft equipped with four or more electric field sensors and a high-voltage corona point that is capable of charging the aircraft. An analytic, closed form solution for the estimate of a (3 x 3) aircraft calibration matrix is derived, and an absolute calibration experiment is used to improve the relative magnitudes of the elements of this matrix. To demonstrate the calibration procedure, we analyze actual calibration date derived from a Lear jet 28/29 that was equipped with five shutter-type field mill sensors (each with sensitivities of better than 1 V/m) located on the top, bottom, port, starboard, and aft positions. As a test of the calibration method, we analyze computer-simulated calibration data (derived from known aircraft and ambient fields) and explicitly determine the errors involved in deriving the variety of calibration matrices. We extend our formalism to arrive at an analytic solution for the ambient field, and again carry all errors explicitly.
    Keywords: METEOROLOGY AND CLIMATOLOGY
    Type: Journal of Geophysical Research (ISSN 0148-0227); 99; D11; p. 22,781-22,792
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2011-08-19
    Description: Consideration is given to the development of the Lightning Mapper Sensor (LMS), a space sensor capable of mapping intracloud and cloud-to-ground lightning discharges from geostationary orbit during day and night. The LMS is expected to have a spatial resolution of 10 km and a detection efficiency of 90 percent. The LMS combines modern solid state mosaic focal planes with extensive on-board signal processing to make it possible to detect weak background-contaminated signals. The LMS is planned to have a 10.5 degree field of view covering all of the continental U.S. The characteristics and design of the LMS are described, noting the possible applications of the sensor.
    Keywords: SPACECRAFT INSTRUMENTATION
    Type: Journal of Geophysical Research (ISSN 0148-0227); 94; 13329-13
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2018-06-12
    Description: We describe the clustering algorithm used by the Lightning Imaging Sensor (LIS) and the Optical Transient Detector (OTD) for combining the lightning pulse data into events, groups, flashes, and areas. Events are single pixels that exceed the LIS/OTD background level during a single frame (2 ms). Groups are clusters of events that occur within the same frame and in adjacent pixels. Flashes are clusters of groups that occur within 330 ms and either 5.5 km (for LIS) or 16.5 km (for OTD) of each other. Areas are clusters of flashes that occur within 16.5 km of each other. Many investigators are utilizing the LIS/OTD flash data; therefore, we test how variations in the algorithms for the event group and group-flash clustering affect the flash count for a subset of the LIS data. We divided the subset into areas with low (1-3), medium (4-15), high (16-63), and very high (64+) flashes to see how changes in the clustering parameters affect the flash rates in these different sizes of areas. We found that as long as the cluster parameters are within about a factor of two of the current values, the flash counts do not change by more than about 20%. Therefore, the flash clustering algorithm used by the LIS and OTD sensors create flash rates that are relatively insensitive to reasonable variations in the clustering algorithms.
    Keywords: Meteorology and Climatology
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2019-06-28
    Description: Not only are scientific objectives and instrument characteristics given of a calibrated optical LIS for the EOS but also for the Tropical Rainfall Measuring Mission (TRMM) which was designed to acquire and study the distribution and variability of total lightning on a global basis. The LIS can be traced to a lightning mapper sensor planned for flight on the GOES meteorological satellites. The LIS consists of a staring imager optimized to detect and locate lightning. The LIS will detect and locate lightning with storm scale resolution (i.e., 5 to 10 km) over a large region of the Earth's surface along the orbital track of the satellite, mark the time of occurrence of the lightning, and measure the radiant energy. The LIS will have a nearly uniform 90 pct. detection efficiency within the area viewed by the sensor, and will detect intracloud and cloud-to-ground discharges during day and night conditions. Also, the LIS will monitor individual storms and storm systems long enough to obtain a measure of the lightning flashing rate when they are within the field of view of the LIS. The LIS attributes include low cost, low weight and power, low data rate, and important science. The LIS will study the hydrological cycle, general circulation and sea surface temperature variations, along with examinations of the electrical coupling of thunderstorms with the ionosphere and magnetosphere, and observations and modeling of the global electric circuit.
    Keywords: EARTH RESOURCES AND REMOTE SENSING
    Type: NASA-TM-4350 , M-680 , NAS 1.15:4350
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2019-07-13
    Description: No abstract available
    Keywords: Meteorology and Climatology
    Type: MSFC-E-DAA-TN20017 , American Meteorological Society Annual Meeting; Jan 04, 2015 - Jan 08, 2015; Phoenix, AZ; United States
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...