The OASIS (Oklahoma Atmospheric Surface-layer Instrumentation System) Project, supported by the National Science Foundation, is enhancing the existing Oklahoma Mesonet over the next 2 years by adding a system of surface flux stations. These flux stations will measure directly the net radiation and ground heat flux and indirectly estimate the sensible heat flux; latent heat flux will be calculated as a residual from the conservation of energy equation. In addition, selected stations will directly measure all four components of the energy budget including sensible and latent heat fluxes.
The OASIS98 Field Project was conducted from 1 July to 15 August 1998 in order to assess the accuracy of surface fluxes measured using the OASIS instrumentation. For this project, the National Center for Atmospheric Research's (NCAR) Atmosphere-Surface Turbulent Exchange Research (ASTER) Facility was used. The ASTER Facility measures surface fluxes by eddy-correlation and measures atmospheric profiles of temperature, moisture, and wind speed and direction. In this paper, the ASTER-measured surface fluxes, which serve as a reference, are compared to those made using OASIS instrumentation. This comparison provides an estimate of the uncertainty associated with OASIS measurements