EFFECTS OF COUPLING IN UNDERSTANDING THE SURFACE ENERGY BALANCE IN THE SNAKE RIVER BASIN, IDAHO

摘要

An accurate estimation of surface fluxes and evapotranspiration is critical in understanding the hydrological and meteorological processes linking the land and the atmosphere. Due to difficulties in obtaining extensive and timely field measurements, land surface and atmospheric models are widely employed in estimating such fluxes. This study focuses on testing the ability of Noah LSM to simulate the surface fluxes both in an uncoupled mode and coupled within an atmospheric model. An agricultural area in the Snake River Basin in Idaho and its surrounding natural vegetation regions are the study area. Two model improvements are tested in this investigation: modification to the calculations of the surface exchange coefficient and the addition of an irrigation scheme to increase available water to crop areas. Results show that these changes are significant factors in proper modeling of hydrological and atmospheric process, but improvements and additional calibration to different regions are still needed.