The energy exchange characteristics of four common landscape types in the high semi-arid plateau in central Oregon, east of the Cascade Range, were evaluated during the summers of 1969 and 1971. The surfaces studied were pumice, meadow, forest, and marsh. A portable environmental data acquisition system was developed for sampling micrometeorological variables with a high degree of precision. The construction and operation of the system is described. The system was deployed for various periods during mid- to late summer at the four experimental sites. Clear weather periods were selected for analysis in order to examine the energy exchange processes at a time of maximum activity. The mean energy budget components for two such clear days were calculated.