Aerosol plays an important role in the radiation budget of Earth__ampersandsignrsquo;s atmospheric system. They serve as cloud condensation nuclei and have a substantial effect on cloud properties. Large concentrations of human made aerosol have been reported to decrease the rainfall as a result of their radioactive and Cloud condensation Nucleus (CCN) activities. On the other hand, heavily polluted clouds evaporate much of their water before precipitation could occur. This paper concentrates at Chennai (13o 04__ampersandsignrsquo; N 80o 17__ampersandsignrsquo; E), situated in the north east of Tamil Nadu on the coast of Bay of Bengal. Aerosol generated in urban areas can act to suppress rainfall which inhibits the collision and coalescence process. Moreover, increased, decreased trend of rainfall quantity recorded during the years 1987 - 2009 on this coastal urban area had been analyzed. Correlation Coefficient between aerosol and rainfall quantity were found using Spearman Rank Correlation technique. Hurst exponent had also found to study the behavior of aerosol concentration on the 262 days time series data observed over the year 2010.