Trends and variability of monthly, seasonal and annual rainfall for the districts of Maharashtra and spatial analysis of seasonality index in identifying the changes in rainfall regime

Knowledge of mean rainfall and its variability of smaller spatial scale are important for the planners in various sectors including water and agriculture. In the present work long rainfall data series (1901-2006) of districts in monthly and seasonal scales are constructed and then mean rainfall and coefficient of variability are analyzed to get the spatial pattern and variability. For the first time long term changes in monthly rainfall in the district scale is identified by trend analysis of rainfall time series and significant changes are obtained. The seasonality index which is the measure of distribution of precipitation throughout the seasonal cycle is used to classify the different rainfall regime within Maharashtra. Also long term changes of the seasonality index are identified by the trend analysis.