Uniform TitleA groundwater-surface water partition for the contiguous United States and select case studies
NameSchaller, Morgan F. (author), Reinfelder, Ying-Fan (chair), Ashley, Gail (internal member), Robinson, David (internal member), Rutgers University, Graduate School - New Brunswick,
Water balance (Hydrology),
DescriptionThe terrestrial water cycle is a highly effective, yet incompletely understood agent for the distribution of continental energy, and hence, the continental energy and water budgets are closely linked. The spatial organization and temporal memory of the groundwater reservoir, and its interaction with the surface water has an integral role in the lateral transport of water and energy, affecting soil moisture distributions, evapotranspiration, precipitation and stream discharge across the continent. The current climate models are unable to account for this lateral component, and consequentially are inadequate at predicting future hydrologic conditions; hence, a separation of groundwater flow from surface water flow is necessary to asses the relative importance of each reservoir across the land surface. Here we present the results of such a groundwater-surface water partition, where 39 years of surface recharge, derived from VIC simulation, are separated from USGS HCDN annual mean observed (naturalized) stream discharge from 1555 basins across the continental U.S. It was found that stream discharge (Qr) may account for 2% to 891% of the total surface recharge (R) across the 1555 basins, suggesting that individual drainage basins export or import significant amounts of water to or from the groundwater reservoir (e.g., a Qr/R value of 2 (200%) for a basin indicates that half the river discharge from that basin is derived from groundwater input from other basins). Detailed investigations of individual basins across the continent in terms of this partition indicate that the control over lateral transport of subsurface water is primarily a function of the subsurface geology. Further, a marked incongruity between the surface drainage flow direction and groundwater flow direction is apparent in several cases – particularly where regional groundwater flow has developed – suggesting that surface drainage as a result of elevation is only partially indicative of subsurface flow regimes. The modulation of surface drainage by the groundwater system suggests that groundwater flow is a significant portion of the continental water cycle. Hence, this wide range of effects attributable to groundwater flow implies that the groundwater reservoir should be included in climate modeling efforts, particularly if estimates of future water resource availability are a goal of such efforts.
NoteIncludes bibliographical references (p. 79-83).
CollectionGraduate School - New Brunswick Electronic Theses and Dissertations
Organization NameRutgers, The State University of New Jersey
RightsThe author owns the copyright to this work.