FIFE: Analysis and results — A review

The initial year of field experimentation of the First ISLSCP Field Experiment (FIFE), conducted over a 15×15km grasslands study area in the central US is complete and analyses are in progress. FIFE was conceived to better understand the interaction of vegetated land surfaces with the atmosphere and how to observe and quantify this interaction using satellite remote sensing. Preliminary data analysis from an April 1988 workshop show that energy and mass flux data collected at several diurnal cycles during different parts of the growing season, are of high quality. From these data we clearly observe the surface vegetation stomatal control on latent heat flux. In addition, the magnitude of this control appears to be measureable from remote sensing observations of reflected radiation. Furthermore, canopy radiometric brightness temperature as measured in the 10.4 to 12.3 μm is linearly related to seasonal variations in canopy aerodynamic temperature and thus may provide a useful measure of sensible heat flux from the surface. Airborne monitoring of the mass and heat flux in the atmospheric boundary layer (ABL) appear adequate to study the energy and mass budgets above the test site and to relate the ABL flux to surface measurements.