Submitted to: American Meterological Society Preprint on Special Symposium on Hydrology
Publication Type: Proceedings
Publication Acceptance Date: January 16, 1998
Publication Date: N/A
Interpretive Summary: No summary.
Desert ecosystems contain sparse vegetation cover which is randomly distributed over the landscape. In many cases where shrubs have invaded primarily grassland ecosystems, it has caused a marked change in vegetation structure and distribution resulting in significant changes in surface roughness and the spatial distribution of bare soil and vegetation. Use of standard formulations with remotely sensed surface temperature observations for estimating water use over these surfaces are shown to be generally unreliable. More recent efforts have been in developing formulations that consider water use of soil and vegetation surfaces and hence would be more applicable to such heterogenous surfaces. Two such models are tested which have potential of being implemented operationally with satellite data for providing regional scale estimates of water use. These models are applied to data collected during JORNEX (JORnada EXperiments) over a mesquite dune site in the USDA-ARS Jornada Experimental Range near Las Cruces, New Mexico. Results suggest that model output is significantly affected by canopy cover parameters which are not well defined for desert vegetation. Future work will be directed in this area.