Profiling of aerosol microphysical properties at several EARLINET/AERONET sites during the July 2012 ChArMEx/EMEP campaign

Abstract

Abstract. The simultaneous analysis of aerosol microphysical properties profiles at different European stations is made in the framework of the ChArMEx/EMEP 2012 field campaign (9–11 July 2012). During and in support of this campaign, five lidar ground-based stations (Athens, Barcelona, Bucharest, Évora, and Granada) performed 72 h of continuous lidar measurements and collocated and coincident sun-photometer measurements. Therefore it was possible to retrieve volume concentration profiles with the Lidar Radiometer Inversion Code (LIRIC). Results indicated the presence of a mineral dust plume affecting the western Mediterranean region (mainly the Granada station), whereas a different aerosol plume was observed over the Balkans area. LIRIC profiles showed a predominance of coarse spheroid particles above Granada, as expected for mineral dust, and an aerosol plume composed mainly of fine and coarse spherical particles above Athens and Bucharest. Due to the exceptional characteristics of the ChArMEx database, the analysis of the microphysical properties profiles' temporal evolution was also possible. An in-depth analysis was performed mainly at the Granada station because of the availability of continuous lidar measurements and frequent AERONET inversion retrievals. The analysis at Granada was of special interest since the station was affected by mineral dust during the complete analyzed period. LIRIC was found to be a very useful tool for performing continuous monitoring of mineral dust, allowing for the analysis of the dynamics of the dust event in the vertical and temporal coordinates. Results obtained here illustrate the importance of having collocated and simultaneous advanced lidar and sun-photometer measurements in order to characterize the aerosol microphysical properties in both the vertical and temporal coordinates at a regional scale. In addition, this study revealed that the use of the depolarization information as input in LIRIC in the stations of Bucharest, Évora, and Granada was crucial for the characterization of the aerosol types and their distribution in the vertical column, whereas in stations lacking depolarization lidar channels, ancillary information was needed. Results obtained were also used for the validation of different mineral dust models. In general, the models better forecast the vertical distribution of the mineral dust than the column-integrated mass concentration, which was underestimated in most of the cases.

Three-dimensional evolution of Saharan dust transport towards Europe based on a 9-year EARLINET-optimized CALIPSO dataset

“…The dust optical depth data used in this study covers the period 2007-2012, and all MACC data are open to the public (http://apps.ecmwf.int/datasets/data/ macc-reanalysis/levtype=sfc/). RegCM4 is an open source, area-limited, sigma-p vertical coordinated regional climate model (Giorgi et al, 2012) based on the hydrostatic core of the Penn State University/National Center for Atmospheric Research (PSU/NCAR) mesoscale model (MM5; Grell et al, 1994). The simulation used in the current study is part of a previous research where the dust optical depth of the model was evaluated against the dust climatological product of this work, after it was fully spatially and temporally collocated with the exact flyby of CALIPSO .…”

Aerosol optical properties derived from POLDER-3/PARASOL (2005–2013) over the western Mediterranean Sea – Part 1: Quality assessment with AERONET and in situ airborne observations

“…-Sky-Grimm counter (1.129 model, Grimm Aerosol Technik; Grimm and Eatough, 2009) This was operated at 632.8 nm with a temporal resolution of 6 s. The instrument integrates light scattering between 30 and 150 • to derive the particle number size distribution over 32 channels between 0.25 and 30 µm in diameter (Grimm and Eatough, 2009). The instrument was available during both TRAQA and ADRIMED, operated inside the aircraft cabin and behind the AVIRAD inlet.…”

A new methodology for PBL height estimations based on lidar depolarization measurements: analysis and comparison against MWR and WRF model-based results

“…POLARIS is based on the detection of the sharp decrease of the aerosol load with height using the range-corrected signal and on the relative changes in the aerosol particle shape with height using the perpendicular-to-parallel signal ratio (δ): low δ values might be related to spherical particle shape and vice versa (Gross et al, 2011). Since POLARIS is based on vertical relative changes, the depolarization calibration is not required to facilitate the procedure.…”