Rainfall variability analysis using precipitation concentration index (PCI) and GIS techniques over kanchipuram district of Tamilnadu, India.

In the world floods and droughts occur in everywhere. Main cause of these natural disasters is sudden change in climatic condition and precipitation patterns. Heavy rainfall in the area results flood and less or no rainfall result drought. So for managing the water resource rainfall variability analysis plays a vital role which used Precipitation Concentration Index (PCI). In this research 41 year long-term monthly precipitation data collected for the Kanchipuram district of Tamilnadu. PCI classified into 5 classes as annual, pre-monsoon, monsoon, post-monsoon and winter rainfall. According to this study highest PCIannual is 32.41 which is recorded in the year 2015 and lowest PCIannual are 13.92 which are recorded in year 2013. The average 41 year PCIannual of the study area recorded as 19.16. According to the range and categories of PCIannual 39.02% of years are in SPID (Strong Irregularity of Precipitation Distribution) while 14.63% years are in MPD (Moderate Precipitation Distribution). Most years 46.34% are in IPD (Irregular Precipitation Distribution). Results of this research indicate that PCI is very useful to manage and developed the natural resources of the study area. [ABSTRACT FROM AUTHOR]