HR: 09:40h
AN: H41B-07 [PDF]
TI: A Comparison of Surface Flux Maps from Remote Sensing-based Models
AU: * Kustas, W P
EM: bkustas@hydrolab.arsusda.gov
AF: William P. Kustas, USDA-ARS Hydrology and Remote Sensing Lab, Beltsville, MD 20705 United States
AU: Timmermans, W J
EM: timmermans@itc.nl
AF: Wim J. Timmermans, 2International Institute for Geo-Information Science and Earth Observation, P.O. Box
6, Enschede, 7500 AA
Netherlands
AB:
A number of energy balance models using remotely sensed boundary conditions for producing spatially distributed maps of
surface fluxes have been proposed. Validation typically involves comparing model output to flux tower observations at a
handful of sites, and hence there is no way of evaluating the reliability of model output for the remaining pixels comprising
a scene. Moreover, there is also the issue of a mismatch between the spatial scale of model output defined by the satellite
pixel resolution and the size and location of the flux footprint or source area contributing to the tower-based flux
measurements. To gain some insight as to the uncertainty in flux estimation from various models over a remote sensing scene
requires one to conduct pixel-by-pixel comparisons of the output. Two models, which have potential for operationally
monitoring ET with satellite data will be described. Some preliminary comparisons of the spatially distributed flux maps
from the two models with remotely sensed imagery collected over a semiarid rangeland site in Arizona and subhumid grassland
site in Oklahoma will be presented and discussed. A framework for conducting future model comparisons will also be
discussed.
DE: 1818 Evapotranspiration
DE: 1878 Water/energy interactions
DE: 1894 Instruments and techniques
SC: Hydrology [H]
MN: 2003 Fall Meeting