Merged Profiles Improve Definition of Planetary Boundary Layer
Published: 2 August 2013
At left, profiles of potential temperature derived from Raman lidar, AERI, radiosonde, and merged Raman lidar + AERI are shown at 5 UT (top) and 17 UT (bottom) on June 16, 2009; PBL heights are indicated by the crosses. The right panel shows potential temperature (in color) derived from merged Raman lidar and AERI measurements for the same day. White dots denote PBL heights derived from Raman lidar + AERI potential temperature profiles; red crosses denote PBL heights determined from potential temperature profiles measured by radiosondes. A new data set for computing planetary boundary layer (PBL) heights is now available to the research community. Principal investigators sponsored by DOE’s Atmospheric System Research program merged near-surface measurements from the Atmospheric Emitted Radiance Interferometer (AERI) with higher resolution and higher altitude measurements from the Raman lidar. The Raman lidar and AERI potential temperature profiles are merged to create a single potential temperature profile for computing PBL heights. Hourly data from the ARM Southern Great Plains site between January 1, 2009 through December 31, 20011 were used in computing the Raman lidar/AERI PBL Height data set.
Researchers took advantage of the ability of the Raman lidar to measure temperature profiles to derive vertical profiles of potential temperature. Additionally they used AERI retrievals of temperature profiles based on measurements of downwelling radiance to derive profiles of potential temperature near the surface. The AERI temperature profiles were obtained using the Value-Added Product AERIPROF3FELTZ. After appropriate scaling to minimize any discontinuities, the AERI potential temperature profiles are spliced onto the bottom of the Raman lidar temperature profiles such that the AERI results are used for altitudes below about 700 meters and the Raman lidar results are used for heights above about 700 meters.
For more information and access to the data, log in to the ARM Data Archive. (Go here to request an account.)
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This work was supported by the U.S. Department of Energy’s Office of Science, through the Biological and Environmental Research program as part of the Atmospheric System Research program.
