Variation in atmospheric aerosol properties over a tropical urban region associated with biomass-burning episodes – a study using satellite data and ground-based measurements

Abstract

The change in aerosol properties and ground-reaching solar irradiance in different spectral bands associated with an intense biomass-burning episode has been examined in the present study. Synchronous ground-based measurements on aerosol optical depth (AOD), erythemal ultraviolet radiation (UV_ery), solar irradiance and light detecting and ranging (LIDAR) observations of aerosol backscatter were carried out in the urban region of Hyderabad, India. Air-mass back-trajectory analysis has been carried out to infer long-range transport of pollutants over the urban environment of Hyderabad. Ground-measured AOD showed ∼50% increase on 3 March 2009 compared to 2 March 2009, along with ∼13% and ∼31% increases in Angström's parameter (α) and turbidity coefficient (β). UV_ery and global solar irradiance showed ∼24% and ∼10% reduction, respectively, on a turbid day (3 March 2009) compared to a normal day (2 March 2009). The Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) AOD₅₅₀ also showed higher values associated with long-range transport of aerosols from biomass burning over the region.

Acknowledgements

The authors wish to thank the Director, NRSC, and DD (RS&GIS-AA), NRSC, for their encouragement and necessary support. The authors thank ISRO-GBP for financial support.