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The sensitivity of southeastern United States climate to varying irrigation vigor

Title: The sensitivity of southeastern United States climate to varying irrigation vigor.
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Name(s): Selman, Christopher, author
Misra, Vasubandhu, author
Type of Resource: text
Genre: Text
Date Issued: 2016-07-16
Physical Form: computer
online resource
Extent: 1 online resource
Language(s): English
Abstract/Description: Four regional climate model runs centered on the Southeast United States (SEUS) assuming a crop growing season of May through October are irrigated at 25% (IRR25), 50% (IRR50), 75% (IRR75), and 100% (IRR100) of the root zone porosity to assess the sensitivity of the SEUS climate to irrigation. A fifth run, assuming no irrigation (CTL), is used as the basis for comparison. Across all IRR runs, it is found that there is a general reduction in seasonal mean precipitation over the irrigated cells relative to CTL. This manifests as an increase in dry (0-1mm/d) days and reduction in>1mm/d rainfall events. A comparative moisture budget reveals that area-averaged precipitation over the irrigated cells displays a reduction in precipitation and runoff in IRR100 with a weaker reduction in IRR25. This is despite an increase in vertically integrated moisture convergence and local evaporation. We find that irrigation increases the lower atmospheric stability, which in turn reduces the convective rainfall over the irrigated areas. Seasonally averaged temperatures reduce over irrigated areas, with the intensity of the reduction increasing with irrigation vigor. This is largely attributed to a repartitioning of sensible heat flux into latent heat flux. There is also, however, a small increase of heat flow to deeper soil layers. Precipitation ahead of transient cold fronts is also reduced by irrigation as they pass over irrigated cells, owing to the increased stability in the lower troposphere. The intensity of this precipitation reduction becomes more intense as irrigation vigor increases. Lastly, heat waves in the SEUS are reduced in intensity over irrigated cells.
Identifier: FSU_libsubv1_wos_000380730500007 (IID), 10.1002/2016JD025002 (DOI)
Keywords: anthropogenic, california central valley, Circulation, climate, irrigation, model, precipitation, reanalysis, regional modeling, resolution, southern great-plains, summer, surface climate, vigor, west-africa
Publication Note: The publisher’s version of record is available at http://www.dx.doi.org/10.1002/2016JD025002
Persistent Link to This Record: http://purl.flvc.org/fsu/fd/FSU_libsubv1_wos_000380730500007
Owner Institution: FSU
Is Part Of: Journal of Geophysical Research-Atmospheres.
2169-897X
Issue: iss. 13, vol. 121

Choose the citation style.
Selman, C., & Misra, V. (2016). The sensitivity of southeastern United States climate to varying irrigation vigor. Journal Of Geophysical Research-Atmospheres. Retrieved from http://purl.flvc.org/fsu/fd/FSU_libsubv1_wos_000380730500007