Editorial Type:
Article
Article Type:
Research Article

Vertical Velocity and Buoyancy Characteristics of Coherent Echo Plumes in the Convective Boundary Layer, Detected by a Profiling Airborne Radar

Qun Miao University of Wyoming, Laramie, Wyoming

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Bart Geerts University of Wyoming, Laramie, Wyoming

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Margaret LeMone National Center for Atmospheric Research,* Boulder, Colorado

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Print Publication:
01 Jun 2006
DOI:
https://doi.org/10.1175/JAM2375.1
Page(s):
838–855
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Abstract

Aircraft and airborne millimeter-wave radar observations are used to interpret the dynamics of radar echoes and radar-inferred updrafts within the well-developed, weakly sheared continental convective boundary layer. Vertically pointing radar reflectivity and Doppler velocity data collected above and below the aircraft, flying along fixed tracks in the central Great Plains during the International H2O Project (IHOP_2002), are used to define echo plumes and updraft plumes, respectively. Updraft plumes are generally narrower than echo plumes, but both types of plumes have the dynamical properties of buoyant eddies, especially at low levels. This buoyancy is driven both by temperature excess and water vapor excess over the ambient air. Plumes that are better defined in terms of reflectivity or updraft strength tend to be more buoyant.

* The National Center for Atmospheric Research is sponsored by the National Science Foundation

Corresponding author address: Bart Geerts, Department of Atmospheric Sciences, University of Wyoming, Laramie, WY 82071. geerts@uwyo.edu

Abstract

Aircraft and airborne millimeter-wave radar observations are used to interpret the dynamics of radar echoes and radar-inferred updrafts within the well-developed, weakly sheared continental convective boundary layer. Vertically pointing radar reflectivity and Doppler velocity data collected above and below the aircraft, flying along fixed tracks in the central Great Plains during the International H2O Project (IHOP_2002), are used to define echo plumes and updraft plumes, respectively. Updraft plumes are generally narrower than echo plumes, but both types of plumes have the dynamical properties of buoyant eddies, especially at low levels. This buoyancy is driven both by temperature excess and water vapor excess over the ambient air. Plumes that are better defined in terms of reflectivity or updraft strength tend to be more buoyant.

* The National Center for Atmospheric Research is sponsored by the National Science Foundation

Corresponding author address: Bart Geerts, Department of Atmospheric Sciences, University of Wyoming, Laramie, WY 82071. geerts@uwyo.edu

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Journal of Applied Meteorology and Climatology

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