Land‐atmosphere coupling manifested in warm‐season observations on the U.S. southern great plains. Issue 2 (28th January 2014)

• Record Type: Journal Article
• Authors: Phillips, Thomas J.; Klein, Stephen A.
• Is Part Of: Journal of geophysical research. Volume 119:Issue 2(2014:Feb.)
• Page Start: 509
• Page End: 528
• Publication Date: 2014-01-28
• Subjects: Atmospheric physics -- Periodicals; Geophysics -- Periodicals; 551.5
• DOI: 10.1002/2013JD020492
• Languages: English
• ISSNs: 2169-897X

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>This study examines several observational aspects of land‐atmosphere coupling on daily average time scales during warm seasons of the years 1997 to 2008 at the Department of Energy Atmospheric Radiation Measurement Program's Southern Great Plains (SGP) Central Facility site near Lamont, Oklahoma. Characteristics of the local land‐atmosphere coupling are inferred by analyzing the covariability of selected land and atmospheric variables that include precipitation and soil moisture, surface air temperature, relative humidity, radiant and turbulent fluxes, as well as low‐level cloud base height and fractional coverage. For both the energetic and hydrological aspects of this coupling, it is found that large‐scale atmospheric forcings predominate, with local feedbacks of the land on the atmosphere being comparatively small much of the time. The relatively weak land feedbacks are manifested especially by (1) the inability of soil moisture to comprehensively impact the coupled land‐atmosphere energetics and (2) the limited recycling of local surface moisture under conditions where most of the rainfall derives from convective cells that originate at remote locations. There is some evidence, nevertheless, that the local land feedback becomes stronger as the soil dries out in the aftermath of precipitation events, or on days when the local boundary layer clouds are influenced by thermal updrafts associated with convection that originates at the surface. Potential implications of these results for climate‐model representation of regional land‐atmosphere coupling also are discussed.</p> </abstract>