Specific U.S. agency plans for participation in GAPP have not yet been formulated.

The objective of GEO-2000 is to ''identify exciting prospects for major advances in understanding the interactions among the full suite of Earth system components.'' As part of NSF's planning, a workshop was convened in Albuquerque, NM (January 31-February 1, 1999) to provide input to the formulation of the hydrologic component of GEO-2000. A summary of the meeting (http://cires.colorado.edu/hydrology/) states that:

". . . Researchers have not been able to quantify many fluxes within the water and companion cycles because they lacked tools to collect and analyze data that capture the complexity and scales at which hydrologic systems operate. The problem is particularly critical where water moves through a phase change or from one medium to another at the medium to large watershed scale where multiple disciplines must work together. New observing capabilities (radar, satellite images, isotope tracers, etc.) and new mathematical tools (fractals, random perturbations of dynamical systems, etc.) provide needed technology, but hydrology lacks an integrated observational system. Educational programs do not provide adequate training for this new era. Example issues are 1) measuring precipitation on, evapotranspiration from, recharge into, and moisture storage within watershed reservoirs where studies are stymied by a lack of mass balances for water, sediments, solutes, etc.; and 2) quantifying the heterogeneous properties of soils and aquifers from geologic understanding for water supply which is threatened by pollution plumes. Watershed-scale data can be used to link disparate space-time scales and couple physical, chemical, and biological states. Scientists can be educated to probe these integrated data sets with advanced diagnostics, computational experiments, and analyses of process, pattern, and probability.