HR: 09:45h
AN: H21I-08    [Abstracts]
TI: Enhanced snow cover products from MODIS for the hydrologic sciences
AU: * Painter, T H
EM: tpainter@nsidc.org
AF: National Snow and Ice Data Center, 449 UCB University of Colorado at Boulder, Boulder, CO 80309-0449 United States
AU: Bales, R
EM: rbales@ucmerced.edu
AF: University of California, School of Engineering, Merced, CA 95344 United States
AB: Near mountain ranges of the globe, over a billion people use melt of the seasonal snow cover as the dominant source of their water resources. These regions are increasingly experiencing the pressing, coupled implications of climate change, drought, and population/demand increase. Enhanced snow cover products have been developed using a multiple endmember spectral mixture analysis model that inverts MODIS surface reflectance products (MOD09) for fractional snow cover, plus the grain size and albedo of the fractional snow cover. Referred to as the MODIS Snow Covered Area and Grain Size/Albedo (MODSCAG) model, this tool is specifically aimed at providing an accurate estimate of snowcover for regional studies in mountainous areas across the globe. The model uses spectral libraries generated with a radiative transfer model for varying grain size snow, adapting the spectral library according to the specific scene solar geometry. Both the albedo and snow-covered area products stimulate advances in hydrologic forecasting by providing more accurate, spatially distributed data than are currently available for assimilation and model evaluation. Data are being developed and provided through an end-to-end NASA REASoN project that includes: (i) standard and custom product development, (ii) distribution through multiple user interfaces and (iii) user support for product evaluation and applications. Currently, MODSCAG is producing snow cover products for hydrologic research clients working in the Colorado River Basin, the Sierra Nevada of California, the Columbia River Basin, and central Tibet. Within the framework of the REASoN project, MODSCAG is designed to address `client' research needs in snow-covered basins around the globe. In this work, we present the introduction of the MODSCAG fractional snow cover products into a model of basin hydrology in the Sierra Nevada. We analyze the differences between the MODSCAG fractional product and the standard MODIS binary snowcover product for mountainous areas in the Southwestern U.S. relative to region, elevation, and time of year.
DE: 1863 Snow and ice (1827)
DE: 1884 Water supply
DE: 1640 Remote sensing
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting