Richard A. Ferrare — NASA - Langley Research Center
Marian B. Clayton — Science Systems and Applications, Inc. (SSAI)
David D. Turner — NOAA- Global Systems Laboratory
Rob K Newsom — Pacific Northwest National Laboratory
Amy Jo Swanson Scarino — Science Systems and Applications, Inc.
Sharon P Burton — NASA - Langley Research Center
Chris A. Hostetler — NASA Langley Research Center
John W. Hair — NASA - Langley Research Center
Michael D. Obland — NASA - Langley Research Center
Raymond Rogers — NASA - Langley Research Center
Category
Atmospheric State & Surface
Description
(a) SGP Raman lidar aerosol backscatter (355 nm) measurements on April 3, 2011. A preliminary indication of the mixing layer (ML) height as determined from the gradient in aerosol backscatter is shown by the white line. (b) Same except for SGP Raman lidar measurements of water vapor mixing ratio.
Accurate determination of the atmospheric mixing-layer (ML) height is important for modeling the transport of aerosols and aerosol precursors and forecasting air quality. Aerosol and water vapor profiles measured by the DOE ARM SGP and TWP (Darwin) ground-based Raman lidars provide direct measurements of the vertical structure of the ML. We have developed automated algorithms that use Haar wavelet covariance transforms to identify sharp gradients in aerosols and water vapor at the top of the ML and use these algorithms to derive ML heights during 2009–2011, including the period of the Midlatitude Continental Convective Clouds Experiment (MC3E). Since recent modifications to these lidars permit continuous temperature profiling, we also compute ML heights using potential temperature profiles derived from the Raman lidar temperature profiles. The Raman lidar ML heights are compared with ML heights derived from coincident radiosonde profiles and from coincident aerosol backscatter profiles measured by the NASA Langley airborne High Spectral Resolution Lidar (HSRL) in June 2009 during the Routine AAF CLOWD Optical Radiative Observations (RACORO) field campaign. We use the Raman lidar aerosol and water vapor profiles and ML heights to derive the fractions of total column precipitable water vapor and aerosol optical thickness within and above the ML and show how the ML heights and these fractions vary with time of day and season.
