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Attributes for MRB_E2RF1 Catchments in Selected Major River Basins of the Conterminous United States: Contact Time, 2002


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2017-04-17 12:51:44


Michael E. Wieczorek, and Andrew E. LaMotte, 2010, Attributes for MRB_E2RF1 Catchments in Selected Major River Basins of the Conterminous United States: Contact Time, 2002: U.S. Geological Survey.


This tabular data set represents the average contact time, in units of days, compiled for every MRB_E2RF1 catchment of Major River Basins (MRBs, Crawford and others, 2006). Contact time, as described in Vitvar and others (2002), is defined as the baseflow residence time in the subsurface. The source data set was the U.S. Geological Survey's (USGS) 1-kilometer grid for the conterminous United States (D.M. Wolock, U.S. Geological Survey, written commun., 2008). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) RF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled [...]


Point of Contact :
Michael E. Wieczorek
Originator :
Michael E. Wieczorek, Andrew E. LaMotte
Metadata Contact :
U.S. Geological Survey
Publisher :
U.S. Geological Survey
Distributor :
U.S. Geological Survey

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Original FGDC Metadata

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This tabular data set was created and used by the U.S. Geological Survey (USGS) specifically to estimate contact time for the 2002 time period per watershed segment in the application of the national SPAtially Referenced Regression On Watershed attributes (SPARROW) model . The SPARROW model relates in-stream water-quality measurements to spatially referenced characteristics of watersheds, including contaminant sources and factors influencing terrestrial and stream transport. The model empirically estimates the origin and fate of contaminants in streams, and quantifies uncertainties in these estimates based on model coefficient error and unexplained variability in the observed data. For more information on the USGS SPARROW model please refer to:

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