HR: 11:50h
AN: H31F-07    [PDF]
TI: VPD Estimation from Land Surface Temperature (MOD11) for global map of evapotranspiration and NPP.
AU: * Hashimoto, H
EM: hiro@ntsg.umt.edu
AF: University of Montana, Missoula, Missoula, MT 59801 United States
AU: * Hashimoto, H
EM: hiro@ntsg.umt.edu
AF: Univeristy of Tokyo, 1-1-1, Yayoi, Tokyo, 113-8657 Japan
AU: Nemani, R
AF: NASA Ames Research Center, Moffet Field, Moffet Field, CA 94035 United States
AU: Yang, F
AF: University of Wisconsin, Madison, Madison, WI 53706 United States
AU: Granger, R
AF: National Water Research Institute, 11 Innovation Boulevard, Saskatoon, S7N 3H5 Canada
AU: Running, S
AF: University of Montana, Missoula, Missoula, MT 59801 United States
AB: Vapor Pressure Deficit (VPD) is one of the key climate variables for ecosystem modeling. Potential evapotranspiration is usually expressed partly as a function of VPD. Stomata regulate the transpiration in response to VPD, thus VPD also influence photosynthesis indirectly. However, unavailability of spatial distribution of VPD makes it difficult to estimate regionally both evapotranspiration and Net Primary Production (NPP). We used the radiometric land surface temperature (LST) for the VPD estimation based on Granger [1991]. Granger [1991] showed that LST could be a good estimator of VPD from the feedback links between the land surface and the overlying air. Better estimates of LST (MODIS11), available daily and globally, allow us to test this method. We tested this method for data of 2001 for India, Amazon and USA. We also examined the spatial variability of the coefficients globally. All the results indicated that this method is feasible for VPD estimation both globally and temporally. The high-resolution maps of VPD can be useful for improving land-atmosphere modeling studies.
DE: 1640 Remote sensing
SC: Hydrology [H]
MN: 2003 Fall Meeting