participate were peer reviewed, and 29 groups were selected to undertake the field studies. The investigators then met twice yearly to agree on the experimental design and on follow-ups. The cost was about $100,000 per investigator per year. Operation of the FIFE data management system consumed about 10 percent of the budget. One of the indirect benefits of FIFE was the interactions that were generated between scientists working at the very small scale (ecologists, micrometeorologists) with those working at the pixel and larger scales.
A general description of FIFE was given by Sellers et al. (1988), while accounts of FIFE information systems have been published by Strebel et al. (1989, 1990a,b). The main scientific findings of FIFE were published in the Journal of Geophysical Research (Sellars et al., 1992), but individual research results are to be found in various other journals, for example, Hall et al. (1989, 1992), American Meteorological Society (1990), and Brutsaert and Sugita (1992).
The operational goals of FIFE were (Sellers et al., 1988):
The simultaneous acquisition of satellite, atmospheric, and surface data:
Satellite data (NOAA-9, NOAA-10, SPOT, Landsat, GOES);
Airborne radiometric, wind, and turbulence data (permitting, for example, the estimation of vertical heat fluxes from the calculation of eddy correlations);
Surface/near-surface fluxes of water vapor, sensible heat, momentum, and CO2; and
Surface/near-surface states (e.g., leaf area index, soil moisture);
Multi-scale observations of biophysical parameters and processes controlling energy and mass exchange at the surface, the goal being to determine how these are manifested in ''satellite resolution" radiometric data; and
Provision of integrated analyses through a highly responsive central data system.
The principal investigators had varying levels of experience to guide them in the operational design of FIFE, particularly with respect to the coordinated collection of data obtained from satellites, aircraft, and ground sensors (and by 29 different research groups). A major challenge that they faced was how data collected on various spatial scales could be combined to achieve the primary research and operational goals of FIFE. Furthermore, the actual relationships among most of the observed parameters