Premium
Effects of spatio‐temporal variability of precipitation on contaminant migration in the vadose zone
Author(s) -
Wang Peng,
Quinlan Peter,
Tartakovsky Daniel M.
Publication year - 2009
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2009gl038347
Subject(s) - vadose zone , arid , infiltration (hvac) , precipitation , environmental science , hydrology (agriculture) , richards equation , groundwater , geology , soil science , climatology , meteorology , soil water , geography , geotechnical engineering , paleontology
Annual meteorological data are routinely used in models of contaminant migration through the vadose zone. In arid and semi‐arid regions, models based on such data yield negligibly small net infiltration rates that are insufficient to cause groundwater contamination. We conduct a series of flow and transport simulations, in which daily data from a weather station serve as input, to demonstrate that precipitation patterns typical of (semi‐)arid regions make the reliance on annual data questionable. We demonstrate that the accuracy of temporally averaged predictions is influenced by the degree of nonlinearity of the Richards equation describing flow in partially saturated porous media. Additional errors are introduced when one ignores topographical and/or urban features that tend to focus and increase local infiltration rates.