A COMPARATIVE APPROACH TO REGIONAL VARIATION IN SURFACE FLUXES USING MOBILE EDDY-CORRELATION TOWERS

We describe a comparative approach to micrometeorological measurements of surface energy, water vapor, and trace gas fluxes, in which mobile eddy correlation towers are moved among sites every 9-14 days, allowi ng both direct and indirect comparison of fluxes among ecosystem types . Structurally distinct ecosystems in Alaskan arctic tundra differed i n the relationships between net radiation and surface energy fluxes, w hereas structurally similar ecosystems showed constant relationships, even when they experienced quite different climate. An intercomparison of two towers simultaneously operated at the same location provided a reference for the systematic error of such comparisons. We suggest ge neral criteria for comparing flux measurements made in different ecosy stems.