EarthRef.org Reference Database (ERR)
Development and Maintenance by the EarthRef.org Database Team

Detailed Reference Information
Famiglietti & Wood 1995
Famiglietti, J.S. and Wood, E.F. (1995). Effects of spatial variability and scale on areally averaged evapotranspiration. Water Resources Research 31: doi: 10.1029/94WR02820. issn: 0043-1397.

This paper explores the effects of spatial variability and scale on areally averaged evapotranspiration. A spatially distributed water and energy balance model is employed to detemine the effect of explicit patterns of land surface characteristics and atmospheric forcing on areally averaged evapotranspiration over a range of increasing spatial scales. The analysis is performed from the local scale to the catchment scale. The study area is King's Creek catchment, an 11.7 km2 watershed located on the native tallgrass prairie of Kansas. It is shown that a threshold scale, or representative elementary area (REA) exists for evapotranspiration modeling. It is shown further that the dominant controls on the scaling behavior of catchment-average evapotranspiration, and thus the size of the REA, depend on the dominant controls on its components (bare-soil evaporation, wet canopy evaporation, and dry canopy transpiration) and whether evapotranspiration is occurring at potential rates or soil- and vegetation-controlled rates. The existence of an REA for evapotranspiration modeling suggests that in catchment areas smaller than this threshold scale, actual patterns of model parameters and inputs may be important factors governing catchment-scale evapotranspiration rates in hydrological models. In models applied at scales greater than the REA scale, spatial patterns of dominant process controls can be represented by their statistical distribution function. It appears that some of our findings are fairly general and will therefore provide a framework for understanding the scaling behavior of areally averaged evapotranspiration at the catchment and larger scales. Our results may have further implications for representing subgrid-scale land surface heterogeneity in hydrological parameterizations for atmospheric models. ¿ American Geophysical Union 1995

BACKGROUND DATA FILES

Abstract

Keywords
Hydrology, Water/energy interactions, Hydrology, Evapotranspiration, Hydrology, Soil moisture, Hydrology, Hydroclimatology
Journal
Water Resources Research
http://www.agu.org/wrr/
Publisher
American Geophysical Union
2000 Florida Avenue N.W.
Washington, D.C. 20009-1277
USA
1-202-462-6900
1-202-328-0566
service@agu.org
Click to clear formClick to return to previous pageClick to submit