抽象的な

Air quality studies over Visakhapatnam, a Case Study of a Coastal Station

Dr V. Lakshmana Rao

Air pollution in general occurs through both anthropogenic and natural sources but in the recent times, increasing population, growth of industries and rapid urbanization are more responsible for the increase in air pollution. The Air pollutants can also be broadly classified into two general groups.1) Primary Pollutants 2) Secondary pollutants. Primary pollutants are (a) fine particles less than 100 μrn (RSPM) (b) coarse particles >100 μm (TSPM), and (c) Sulfur and Nitrogen compounds, Secondary pollutants are formed by chemical and photochemical reactions of primary pollutants (acid rains). In the present study an attempt is made to see the implications of air pollution and its effects on the environment of an industrially developed coastal city. As a test case the data of the major primary pollutants like SO2, No2, TSPM (Total suspended particulate matter) and RSPM (Respirable Suspended Particulate Matter) for the years of 2001-2010 at various locations in Visakhapatnam are analyzed. The factors influencing the dispersion and dilution of air pollutants depends on mainly Meteorological and topographical factors. Here we discuss the seasonal rainfall distributions and local stability conditions how influence the dispersion and dilution of pollutants in annual time scales. Also an attempt is made on how these primary pollutants vary in a coastal developed city in the global warming era on seasonal and annual time scales.