Articles | Volume 12, issue 10
Atmos. Chem. Phys., 12, 4513–4524, 2012

Special issue: European Integrated Project on Aerosol-Cloud-Climate and Air...

Atmos. Chem. Phys., 12, 4513–4524, 2012

Research article 24 May 2012

Research article | 24 May 2012

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

M. Komppula1, T. Mielonen1, A. Arola1, K. Korhonen1, H. Lihavainen2, A.-P. Hyvärinen2, H. Baars3, R. Engelmann3, D. Althausen3, A. Ansmann3, D. Müller4,3,*, T. S. Panwar5, R. K. Hooda5,2, V. P. Sharma5, V.-M. Kerminen6,2, K. E. J. Lehtinen1,7, and Y. Viisanen2 M. Komppula et al.
  • 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

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.

Final-revised paper