%0 Journal Article %T Radiative Impact of Fireworks at a Tropical Indian Location: A Case Study %A B. P. Singh %A A. K. Srivastava %A S. Tiwari %A S. Singh %A R. K. Singh %A D. S. Bisht %A D. M. Lal %A A. K. Singh %A R. K. Mall %A Manoj K. Srivastava %J Advances in Meteorology %D 2014 %I Hindawi Publishing Corporation %R 10.1155/2014/197072 %X During Diwali festival, extensive burning of crackers and fireworks is made. Weeklong intensive observational campaign for aerosol study was carried out at a representative urban location in the eastern Indo-Gangetic Plain (IGP), Varanasi (25.3¡ãN, 83.0¡ãE), from October 29 to November 04, 2005 (Diwali on November 01, 2005), to investigate behavioral change of aerosol properties and radiative forcing between firework affected and nonaffected periods. Results show a substantial increase (~27%) in aerosol optical depth, aerosol absorption coefficients, and aerosol scattering coefficients during affected period as compared to non-affected periods. Magnitudes of radiative forcing at top of atmosphere during affected and non-affected periods are found to be +10£¿¡À£¿1 and +12£¿¡À£¿1£¿Wm£¿2, respectively, which are £¿31£¿¡À£¿7 and £¿17£¿¡À£¿5£¿Wm£¿2, respectively, at surface. It suggests an additional cooling of ~20% at top of atmosphere, ~45% cooling at surface, and additional atmospheric heating of 0.23£¿Kday£¿1 during fireworks affected period, which is ~30% higher than the non-affected period average. 1. Introduction Importance of aerosols in regional and global climate has gained wide knowledge base during the last couple of decades. General impact of these aerosols is to cool the atmosphere and to compensate the atmospheric warming caused due to enhanced greenhouse gases. However, atmospheric warming due to aerosols is also noticed when absorbing particles, such as black carbon (soot) and/or mineral dust, are present [1, 2]. Significant heating to the atmosphere may play a crucial role in various boundary layer processes under favorable atmospheric conditions [3]. The presence of such aerosols is higher in the atmospheric boundary layer [4], but they are also reported in the free troposphere till stratosphere. Boundary layer aerosols are characterized as short-lived and showed spatiotemporal variation in mass and number concentrations. Depending on weather condition and location, the regional variability in physical, chemical, and optical characteristics of aerosols is influenced by mixing various types of aerosols, produced by different natural and/or anthropogenic processes [3, 5], for example, aerosol production from biomass burning [6], biogenic production [7], industrial effluents [8], and so forth. The impact of aerosol is also found to be associated with climatic elements [9]. During recent decades, there have been a number of studies to characterize aerosols on local scale; however, studies on instant increment of aerosols within 1-2 days, due to fireworks, are %U http://www.hindawi.com/journals/amete/2014/197072/