HR: 09:45h
AN: B41E-06    [Abstracts]
TI: Modeling Land Surface Phenology Using Earthlight
AU: * Henebry, G M
EM: Geoffrey.Henebry@sdstate.edu
AF: Geographic Information Science Center of Excellence (GIScCE), South Dakota State University, Wecota Hall, 506B 1021 Medary Ave., Brookings, SD 57007 United States
AB: Microwave radiometers have long been used in earth observation, but the coarse spatial resolution of the data has discouraged its use in investigations of the vegetated land surface. The Advanced Microwave Scanning Radiometer (AMSR-E) on the Aqua satellite acquires multifrequency observations twice daily (1:30 and 13:30). From these brightness temperatures come two data products relevant to land surface phenology: soil moisture and vegetation water content. Although the nominal spatial resolution of these products is coarse (25 km), the fine temporal sampling allows characterization of the diel variation in surface moisture as contained in the uppermost soil layer and bound in the vegetation canopy. The ephermal dynamics of surficial soil moisture are difficult to validate due to the scale discrepancy between the 625 sq km coverage of a single pixel and the sparse network of weather stations. In contrast, canopy dynamics are more readily validated using finer spatial resolution data products and/or ecoregionalizations. For sites in the North American Great Plains and Northern Eurasia dominated by herbaceous vegetation, I will present land surface phenologies modeled using emitted earthlight and compare them with land surface phenologies modeled using reflected sunlight. I will also explore whether some key climate modes have a significant effect on the microwave-retrieved land surface phenologies.
DE: 0429 Climate dynamics (1620)
DE: 0438 Diel, seasonal, and annual cycles (4227)
DE: 0476 Plant ecology (1851)
DE: 0480 Remote sensing
DE: 1631 Land/atmosphere interactions (1218, 1843, 3322)
SC: Biogeosciences [B]
MN: Fall Meeting 2005