How well can regional fluxes be derived from smaller-scale estimates?

Simultaneous aircraft and tower data obtained in the relatively simple terrain of the western Alaskan tundra were used to determine the extent to which surface type variation can be related to regional-scale fluxes of heat, moisture, and other properties. Surface type was classified as lake or land with an aircraft-borne infrared thermometer, and flight-level heat and moisture fluxes were related to surface type. The magnitude and variety of sampling errors inherent in eddy correlation flux estimation place limits on how well any flux can be known even in simple geometries. Because of the presence of intrinsic and site-specific uncertainties, regional-scale flux of heat and moisture using aircraft observations in our study area can be reasonably verified to be estimated correctly from linear combinations of smaller-scale estimates only to within a factor of 1.5. -from Authors