Findings and Recommendations - Basic Research Opportunities in Earth Science - page 86

geomorphology, and coastal zone processes. Currently, research in these diverse
fields is funded mainly through the G&P and Hydrologic Sciences core
programs.
Hydrology
In hydrology, many of the advances of the last two decades have resulted
from the increasing ability to measure with greater spatial and temporal resolution
the fluxes and states that are critical for quantifying the water balance.
Enhancements in computer and information technology have made possible, for
example, the development and testing of distributed catchment models using
remote-sensing information at scales ranging from tens of meters to tens of
kilometers. Better characterization of the heterogeneous nature of subsurface flow
has led to an improved understanding of the movement of groundwater and the
fate of contaminants. Knowledge of the nature and severity of floods and
droughts has increased, although much remains to be done particularly in
connection with discerning human influences on the global energy and water
balances and in forecasting hydrologic extremes.
Understanding and quantifying the various chemical cycles of the Critical
Zone require extremely accurate hydrologic balances for both very short and very
long time spans. New efforts are required to measure and model the water
pathways through vegetation and the vadose zone into the groundwater and
below, as well as to determine the corresponding biogeochemical interactions and
define human influences on hydrologic and ecologic systems. These efforts are
needed in a variety of geologic, soil, climate, and vegetation settings and for
spatial scales that range from a few meters at the hillslope scale to basin-wide and
continental scales.
Recommendation: Owing to the significant opportunities for progress in the
understanding of hydrologic systems, particularly through coordinated
studies of the Critical Zone, EAR should continue to build programs in the
hydrologic sciences.
Increased support of the hydrological science program would improve the
success rate of proposals (19%) and complement the focused, largely intramural
hydrology programs in the National Oceanic and Atmospheric Administration
(NOAA) (e.g., the Global Energy and Water Cycle Experiment [GEWEX]
Continental-Scale International Project) and the USGS Water Resources
Division, as well as the remote-sensing hydrology programs in NASA (GEWEX,
Land Surface Hydrology Program).