Water Science and Application – serie

Published by the American Geophysical Union as part of the Water Science and Application Series, Volume 6.During the past four decades, computer-based mathematical models of watershed hydrology have been widely used for a variety of applications including hydrologic forecasting, hydrologic design, and water resources management. These models are based on general mathematical descriptions of the watershed processes that transform natural forcing (e.g., rainfall over the landscape) into response (e.g., runoff in the rivers). The user of a watershed hydrology model must specify the model parameters before the model is able to properly simulate the watershed behavior.

Published by the American Geophysical Union as part of the Water Science and Application Series, Volume 7.The Deschutes is a "peculiar" dammed river in Oregon. Its dramatic juxtaposition of geology, topography, and climate presents a virtual textbook of landforms and geomorphic processes revealing Quaternary, Holocene, and very recent events of immense magnitude. Along the active volcanism and tectonism, the present riverine landscape reflects this episodic geomorphic history, as remnants of fluviatle features, huge bars and boulders, mantle the landscape. A Peculiar River: Geology, Geomorphology, and Hydrology of the Deschutes River, Oregon tells a fascinating story about a "striking, sometimes intimidating, landscape that serves to question generalities and is a laboratory in which to study special landforms and the processes that produce them."

Published by the American Geophysical Union as part of the Water Science and Application Series, Volume 3.Land surface hydrology integrates various physical, chemical and biological processes that occur above, on, and below the surface of the Earth. As a result, it is critical to accurately account for land surface processes within predictive models of hydrology, meteorology, and climate.One of our main difficulties, however, concerns the broad range of spatial and temporal scales that characterize land surface hydrological processes. For example, we determine infiltration by pore scale physics, while soil hydraulic conductivity remains a field scale property. Photosynthesis, respiration, and transpiration occur at the leaf scale. Runoff is a catchment scale process, and the variability of groundwater storage is a regional scale issue. Turbulence in land-atmosphere exchanges of heat, moisture, and momentum occur on the order of seconds to minutes, while variations in land surface and air temperatures occur much more gradually: on the order of hours. The persistence of floods and droughts is seasonal to annual, and so is the effect of El Nino on regional hydrology. Long-term climate effects occur much more slowly, on the order of years to decades.