Evaluation of an empirical orthogonal function–based method to downscale soil moisture patterns based on topographical attributes

摘要: Soil moisture influences many hydrologic applications including agriculture, land management and flood prediction. Most remote-sensing methods that estimate soil produce coarse resolution patterns, so are required to downscale such patterns the resolutions by these (e.g. 10- 30-m grid cells). At resolutions, topography is known affect patterns. Although have been proposed based on topography, they usually require availability of past high-resolution from application region. The objective this article determine whether a single topographic-based downscaling method can be used at multiple locations without relying detailed local observations. evaluated developed basis empirical orthogonal function (EOF) analysis space–time data reference catchment. most important EOFs then estimated topographic attributes, associated expansion coefficients spatial-average moisture. To test portability EOF-based method, it separately using four sets (Tarrawarra, Tarrawarra 2, Cache la Poudre Satellite Station), relationships derived compared. In addition, each applied not only for catchment where was but also other three catchments. results suggest EOF performs well location developed, its performance degrades when Copyright © 2011 John Wiley & Sons, Ltd.