A Study on the Rainfall Changes of Orathanadu Taluk Thanjavur District Tamil Nadu Using GIS

Agriculture is the most fundamental activity of mankind. This study is mainly based on agriculture, which is affected in a major way by rainfall changes. Ortahnadu taluks is located in the Eastern part of Thanjavur district in TamilNadu. The winter season (Jan- Feb) summer season (Mar-May) and Rainfall changes are analyzed. Two sets of data have been taken (2000 and 2009). The three sets of rainfall stations are Neivasal, Orathanadu and vettikadu. In 2000, during the Winter season Neivasal received 22 mm, Orathanadu received 3.7 mm the minimum rainfall and vettikadu 50 mm the maximum rainfall. In 2000, during the summer season Neivasal received 54.7 mm the minimum rainfall, Orathanadu received 287.2 mm the maximum rainfall and vettikadu received 211 mm rainfall. In 2009, winter rainfall and summer rainfall received by Neivasal was 24 mm the minimum of the season and 94.7 the maximum of the summer rainfall respectively. In 2009 Orathanadu received 1894 mm the maximum rainfall of the season 2.6 mm the minimum of winter rainfall and 234.3mm the maximum of summer rainfall. Orathanadu Taluk has received a total annual rainfall of 628.6 mm in 2000. The maximum rainfall of 552.6 mm was received during the summer season (Mar May) and the minimum rainfall of 75.7 mm was received during 2000 winter (Jan- Feb).