OPEN ACCESS

Articles online

Spectral Variation of Total Column Aerosol Optical Depth over Rajkot: A Tropical Semi-arid Indian Station

Category: Articles

Volume: 7 | Issue: 1 | Pages: 33-45
DOI: 10.4209/aaqr.2006.08.0012
PDF | RIS | BibTeX

Ritweej Rajeev Ranjan, H.P. Joshi, K.N. Iyer

  • Department of Physics, Saurashtra University, Rajkot-360005, India

Abstract

Spectral aerosol optical depth (AOD) measurements, estimated from two hand-held, microprocessor-based sun photometers [MICROTOPS-II (version 2.43 & 5.5)] over Rajkot, India were analyzed from March 2005 to March 2006 (a total of 167 days of clear-sky observations). The results showed seasonal variation with high values in summer and low values in winter. The summer increase is found to be due to the high wind speed producing larger amounts of wind-driven dust particles. The winter AOD values decrease more at higher wavelengths, indicating a general reduction in the number of bigger particles. Also during the winter months the wind direction changed to southerly and southeasterly bringing air from more rural areas to the measurement site. The amplitude of the observed high AOD values in summer is higher (low during winter) for longer wavelengths, which shows that coarse particles contribute more to the observed variation as compared to sub-micron particles. To characterize the aerosol optical depths, the Ångström parameters α and β were used.

Keywords

Atmospheric aerosol Aerosol optical depth Ångström parameters Sun photometer.


Related Article

Langley Calibration of Sunphotometer using Perez’s Clearness Index at Tropical Climate

Jackson H.W. Chang , Nurul H.N. Maizan, Fuei Pien Chee, Jedol Dayou
Volume: 18 | Issue: 5 | Pages: 1103-1117
DOI: 10.4209/aaqr.2016.10.0455
PDF

Aerosol Optical Depth, Ozone and Water Vapor Measurements over Gadanki, A Tropical Station in Peninsular India

A. K. Srivastava , P. C. S. Devara, Y. Jaya Rao, Y. Bhavanikumar, D. N. Rao
Volume: 8 | Issue: 4 | Pages: 459-476
DOI: 10.4209/aaqr.2008.05.0015
PDF

Critical Emissions from the Largest On-Road Transport Network in South Asia

Saroj Kumar Sahu , Gufran Beig, Neha Parkhi
Volume: 14 | Issue: 1 | Pages: 135-144
DOI: 10.4209/aaqr.2013.04.0137
PDF

Ambient Air Quality during Diwali Festival over Kolkata – A Mega-City in India

A. Chatterjee , C. Sarkar, A. Adak, U. Mukherjee, S.K. Ghosh, S. Raha
Volume: 13 | Issue: 3 | Pages: 1133-1144
DOI: 10.4209/aaqr.2012.03.0062
PDF
;