1Finnish Meteorological Institute, 70211 Kuopio, Finland
2Finnish Meteorological Institute, 00101 Helsinki, Finland
3Leibniz Institute for Tropospheric Research, 04318 Leipzig, Germany
4Atmospheric Remote Sensing Laboratory, Gwangju Institute of Science and Technology, Buk-Gu Gwangju 500-712, Republic of Korea
5The Energy and Resource Institute, Dabari Seth Block, IHC Complex, Lodhi Road, 110 003 New Delhi, India
6Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, Finland
7Department of Applied Physics, University of Eastern Finland, 70211 Kuopio, Finland
*now at: Science Systems and Applications, Inc., MS 475 NASA Langley Research Center, Hampton, VA, 23681, USA
Received: 06 Sep 2010 – Discussion started: 22 Dec 2010
Abstract. One year of multi-wavelength (3 backscatter + 2 extinction + 1 depolarization) Raman lidar measurements at Gual Pahari, close to New Delhi, were analysed. The data was split into four seasons: spring (March–May), summer (June–August), autumn (September–November) and winter (December–February). The vertical profiles of backscatter, extinction, and lidar ratio and their variability during each season are presented. The measurements revealed that, on average, the aerosol layer was at its highest in spring (5.5 km). In summer, the vertically averaged (between 1–3 km) backscatter and extinction coefficients had the highest averages (3.3 Mm−1 sr−1 and 142 Mm−1 at 532 nm, respectively). Aerosol concentrations were slightly higher in summer compared to other seasons, and particles were larger in size. The autumn showed the highest lidar ratio and high extinction-related Ångström exponents (AEext), indicating the presence of smaller probably absorbing particles. The winter had the lowest backscatter and extinction coefficients, but AEext was the highest, suggesting still a large amount of small particles.
Revised: 27 Apr 2012 – Accepted: 27 Apr 2012 – Published: 24 May 2012
Komppula, M., Mielonen, T., Arola, A., Korhonen, K., Lihavainen, H., Hyvärinen, A.-P., Baars, H., Engelmann, R., Althausen, D., Ansmann, A., Müller, D., Panwar, T. S., Hooda, R. K., Sharma, V. P., Kerminen, V.-M., Lehtinen, K. E. J., and Viisanen, Y.: Technical Note: One year of Raman-lidar measurements in Gual Pahari EUCAARI site close to New Delhi in India – Seasonal characteristics of the aerosol vertical structure, Atmos. Chem. Phys., 12, 4513-4524, doi:10.5194/acp-12-4513-2012, 2012.