The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform
Dorothy K. Hall - One of the best experts on this subject based on the ideXlab platform.
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Remote Sensing of Terrestrial Snow and Ice for Global Change Studies
Earth Observation of Global Change, 2008Co-Authors: Richard Kelly, Dorothy K. HallAbstract:Snow and Ice play a significant role in the Earth’s water cycle and are sensitive and informative indicators of climate change. Significant changes in terrestrial Snow and Ice water storage are forecast, and while evidence of large-scale changes is emerging, in situ measurements alone are insufficient to help us understand and explain these changes. Imaging remote sensing systems are capable of successfully observing Snow and Ice in the cryosphere. This chapter examines how those remote sensing sensors, that now have more than 35 years of observation records, are capable of providing information about Snow cover, Snow water equivalent, Snow melt, Ice sheet temperature and Ice sheet albedo. While significant progress has been made, especially in the last 5 years, a better understanding is required of the records of satellite observations of these cryospheric variables.
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MODIS Snow and Ice Production
2002Co-Authors: Dorothy K. Hall, Paul HoserAbstract:Daily, global Snow cover maps, and sea Ice cover and sea Ice surface temperature (IST) maps are derived from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS), are available at no cost through the National Snow and Ice Data Center (NSIDC). Included on this CD-ROM are samples of the MODIS Snow and Ice products. In addition, an animation, done by the Scientific Visualization studio at Goddard Space Flight Center, is also included.
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MODIS Snow and Ice Products from the NSIDC DAAC
Earth Observing Systems II, 1997Co-Authors: Greg R. Scharfen, Dorothy K. Hall, George A. RiggsAbstract:The National Snow and Ice Data CEnter (NSIDC) Distributed Active Archive Center (DAAC) provides data and information on Snow and Ice processes, especially pertaining to interactions among Snow, Ice, atmosphere and ocean, in support of research on global change detection and model validation, and provides general data and information servIces to the cryospheric and polar processes research community. THe NSIDC DAAC is an integral part of the multi- agency-funded support for Snow and Ice data management servIce at NSIDC. The Moderate Resolution Imaging Spectroradiometer (MODIS) will be flown on the first Earth Observation System (EOS) platform in 1998. The MODIS Instrument Science Team is developing geophysical products form data collected by the MODIS instrument, including Snow cover and sea Ice products which will be archived and distributed by the NSIDC DAAC. The MODIS Snow and Ice mapping algorithms will generate global Snow, lake Ice and sea Ice cover products on a daily basis. These products will augment the existing record of satellite-derived Snow cover and sea Ice products that began about 30 years ago. The characteristics of these products, their utility, and comparisons to other data sets are discussed. Current developments and issues are summarized.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
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First Moderate Resolution Imaging Spectroradiometer (MODIS) Snow and Ice Workshop
1995Co-Authors: Dorothy K. HallAbstract:This document is a compilation of summaries of talks presented at a 2-day workshop on Moderate Resolution maging Spectroradiometer (MODIS) Snow and Ice products. The objectives of the workshop were to: inform the Snow and ce community of potential MODIS products, seek advIce from the participants regarding the utility of the products, and letermine the needs for future post-launch MODIS Snow and Ice products. Four working groups were formed to discuss at-launch Snow products, at-launch Ice products, post-launch Snow and Ice products and utility of MODIS Snow and Ice products, respectively. Each working group presented recommendations at the conclusion of the workshop.
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Accessing the MODIS Snow and Ice products at the NSIDC DAAC
IGARSS 2000. IEEE 2000 International Geoscience and Remote Sensing Symposium. Taking the Pulse of the Planet: The Role of Remote Sensing in Managing t, 1Co-Authors: Greg R. Scharfen, Dorothy K. Hall, S.j.s. Khalsa, S. Khalsa, J. D. Wolfe, Melinda Marquis, G.a. Rigg, B. McleanAbstract:The Moderate Resolution Imaging Spectroradiometer (MODIS) is the key instrument for Snow and Ice studies supported by the Terra satellite, launched in December 1999. The spectral and spatial resolutions of MODIS represent a considerable improvement in capability for global cryospheric monitoring over comparable existing systems. The MODIS Snow and Ice products augment the existing record of satellite-derived Snow cover and sea Ice products that began about 30 years ago. The MODIS Snow and Ice products are archived and will be distributed by the National Snow and Ice Data Center (NSIDC) as part of NASA's Earth Observing System Data and Information System (EOSDIS) beginning in the summer of 2000. This paper summarizes the content and format of the MODIS Snow and Ice products, and describes user support and data access at NSIDC.
K. C. Jezek - One of the best experts on this subject based on the ideXlab platform.
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Recent Progress in Snow and Ice Research
Reviews of Geophysics, 1991Co-Authors: J. A. Richter-menge, Samuel C. Colbeck, K. C. JezekAbstract:A review of Snow and Ice research in 1987-1990 is presented, focusing on the effects of layers in seasonal Snow covers, Ice mechanics on fresh water and sea Ice, and remote sensig of polar Ice sheets. These topics provide useful examples of general needs in Snow and Ice research applicable to most areas, such as better representation in models of detailed processes, controlled laboratory experiments to quantify processes, and field studies to provide the appropriate context for interpretation of processes from remote sensing.
Edgar L. Andreas - One of the best experts on this subject based on the ideXlab platform.
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Parameterizing Scalar Transfer over Snow and Ice: A Review
Journal of Hydrometeorology, 2002Co-Authors: Edgar L. AndreasAbstract:Abstract Evaluating the profiles of wind speed, temperature, and humidity in the atmospheric surface layer or modeling the turbulent surface fluxes of sensible and latent heat over horizontally homogeneous surfaces of Snow or Ice requires five pieces of information. These are the roughness lengths for wind speed (z0), temperature (zT), and humidity (zQ) and the stratification corrections for the wind speed and scalar profiles ψm and ψh, respectively. Because over Snow and Ice the atmospheric surface layer is often stably stratified, the discussion here focuses first on which of the many suggested ψm and ψh functions to use over Snow and Ice. On the basis of four profile metrics—the critical Richardson number, the Deacon numbers for wind speed and temperature, and the turbulent Prandtl number—the manuscript recommends the Holtslag and de Bruin ψm and ψh functions because these have the best properties in very stable stratification. Next, a reanalysis of five previously published datasets confirms the valid...
J. A. Richter-menge - One of the best experts on this subject based on the ideXlab platform.
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Recent Progress in Snow and Ice Research
Reviews of Geophysics, 1991Co-Authors: J. A. Richter-menge, Samuel C. Colbeck, K. C. JezekAbstract:A review of Snow and Ice research in 1987-1990 is presented, focusing on the effects of layers in seasonal Snow covers, Ice mechanics on fresh water and sea Ice, and remote sensig of polar Ice sheets. These topics provide useful examples of general needs in Snow and Ice research applicable to most areas, such as better representation in models of detailed processes, controlled laboratory experiments to quantify processes, and field studies to provide the appropriate context for interpretation of processes from remote sensing.
Roger G. Barry - One of the best experts on this subject based on the ideXlab platform.
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The Role of Snow and Ice in the Climate System
2007Co-Authors: Roger G. BarryAbstract:Global Snow and Ice cover (the 'cryosphere') plays a major role in global climate and hydrology through a range of complex interactions and feedbacks, the best known of which is the Ice - albedo feedback. Snow and Ice cover undergo marked seasonal and long term changes in extent and thickness. The perennial elements - the major Ice sheets and permafrost - play a role in present-day regional and local climate and hydrology, but the large seasonal variations in Snow cover and sea Ice are of importance on continental to hemispheric scales. The characteristics of these variations, especially in the Northern Hemisphere, and evidence for recent trends in Snow and Ice extent are discussed.
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The role of Snow and Ice in the global climate system: a review
Polar Geography, 2002Co-Authors: Roger G. BarryAbstract:Global Snow and Ice cover (the “cryosphere”) plays a major role in global climate and hydrology through a range of complex interactions and feedbacks, the best known of which is the Ice-albedo feedback. Snow and Ice cover undergo marked seasonal and long-term changes in extent and thickness. In the Proterozoic era, for example, a long-lived “Snowball” Earth has been proposed, while in the Pleistocene epoch, glacial and interglacial intervals alternated in a quasi-periodic manner, but with a smaller spatial extent. The perennial elements of the cryosphere—the major Ice sheets and permafrost—play a role in present-day regional and local climate and hydrology, but the large seasonal variations in Snow cover and sea Ice are of importance on continental to hemispheric scales. The characteristics of these variations, especially in the Northern Hemisphere, and evidence for recent trends in Snow and Ice extent are discussed. The relative roles of natural variability in the climate-system forcing of such trends, v...
