Aerosol and Atmospheric Research Laboratory, Department of Physics, Sri Krishnadevaraya University, Anantapur, 515003 Andhra Pradesh, India; Institute of Environmental Engineering, National Chiao Tung University, Hsinchu, Taiwan; Institute of Low Temperature Science, Hokkoido University, Sapporo, 0600819, Japan; School of Physics, University of KwaZulu-Natal, Durban, 4000, South Africa; Department of Physics, Yogi Vemana University, Kadapa, 516003, India
Reddy, B.S.K., Aerosol and Atmospheric Research Laboratory, Department of Physics, Sri Krishnadevaraya University, Anantapur, 515003 Andhra Pradesh, India, Institute of Low Temperature Science, Hokkoido University, Sapporo, 0600819, Japan; Kumar, K.R., Aerosol and Atmospheric Research Laboratory, Department of Physics, Sri Krishnadevaraya University, Anantapur, 515003 Andhra Pradesh, India, School of Physics, University of KwaZulu-Natal, Durban, 4000, South Africa; Balakrishnaiah, G., Institute of Environmental Engineering, National Chiao Tung University, Hsinchu, Taiwan; Gopal, K.R., Aerosol and Atmospheric Research Laboratory, Department of Physics, Sri Krishnadevaraya University, Anantapur, 515003 Andhra Pradesh, India; Reddy, R.R., Aerosol and Atmospheric Research Laboratory, Department of Physics, Sri Krishnadevaraya University, Anantapur, 515003 Andhra Pradesh, India; Sivakumar, V., School of Physics, University of KwaZulu-Natal, Durban, 4000, South Africa; Arafath, S.M., Aerosol and Atmospheric Research Laboratory, Department of Physics, Sri Krishnadevaraya University, Anantapur, 515003 Andhra Pradesh, India; Lingaswamy, A.P., Aerosol and Atmospheric Research Laboratory, Department of Physics, Sri Krishnadevaraya University, Anantapur, 515003 Andhra Pradesh, India; Pavankumari, S., Aerosol and Atmospheric Research Laboratory, Department of Physics, Sri Krishnadevaraya University, Anantapur, 515003 Andhra Pradesh, India; Umadevi, K., Aerosol and Atmospheric Research Laboratory, Department of Physics, Sri Krishnadevaraya University, Anantapur, 515003 Andhra Pradesh, India; Ahammed, Y.N., Department of Physics, Yogi Vemana University, Kadapa, 516003, India
Surface measurements of aerosol physical properties were made at Anantapur (14.62°N, 77.65°E, 331 m a. s. l), a semiarid rural site in India, during August 2008-July 2009. Measurements included the segregated sizes of aerosolsas as well as total mass concentration and size distributions of aerosols measured at low relative humidity (RH<75%) using a Quartz Crystal Microbalance (QCM) in the 25-0.05 μm aerodynamic diameter range. The hourly average total surface aerosol mass concentration in a day varied from 15 to 70 μg m-3, with a mean value of 34.02±9.05 μg m-3 for the entire study period. A clear diurnal pattern appeared in coarse, accumulation and nucleation-mode particle concentrations, with two local maxima occurring in early morning and late evening hours. The concentration of coarse-mode particles was high during the summer season, with a maximum concentration of 11.81±0.98 μg m-3 in the month of April, whereas accumulationmode concentration was observed to be high in the winter period contributed >68% to the total aerosol mass concentration. Accumulation aerosol mass fraction, Af (= Ma/Mt) was highest during winter (mean value of Af ~ 0.80) and lowest (Af ~ 0.64) during the monsoon season. The regression analysis shows that both Reff and Rm are dependent on coarse-mode aerosols. The relationship between the simultaneous measurements of daily mean aerosol optical depth at 500 nm (AOD500) and PM2.5 mass concentration ([PM2.5]) shows that surface-level aerosol mass concentration increases with the increase in columnar aerosol optical depth over the observation period. © 2012 Chinese National Committee for International Association of Meteorology and Atmospheric Sciences, Institute of Atmospheric Physics, Science Press and Springer-Verlag Berlin Heidelberg.