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Abstract
Measurements of aerosol vertical profiles were performed in Gual Pahari (28º26’N, 77º09’E, 243 m a.s.l.), India, about 30 km south of Delhi. The one-year lidar measurements were conducted from March 2008 to March 2009. The measurements belong to the frame of the EUCAARI (European Integrated project on Aerosol Cloud Climate and Air Quality interactions) project. The measurements were performed with an automated multi-wavelength Raman-lidar called PollyXT. The output of the instrument includes vertical profiles of the particle backscattering coefficient at three wavelengths (355, 532 & 1064 nm) and of the particle extinction coefficient at two wavelengths (355 & 532 nm). Also the particle depolarisation ratio can be determined at 355 nm. The vertical resolution of the system is 30 meters. Preliminary results reveal up to 5 km thick aerosol layers, with AODs well above one. The lidar-based AOD values were in line with the values obtained from MODIS (The Moderate Resolution Imaging Spectroradiometer) satellite instrument. Often multi-layer aerosol structure is observed and with backward trajectories the sources areas of various layers can be defined. Furthermore, statistics of the boundary layer evolution will be defined and the measurements will be compared with ground-based measurements at the site. A detailed comparison with AOD obtained from lidar and MODIS will be done. The typical backscattering and extinction profiles for the different seasons will be provided.