On some characteristic features of daily rainfall over Madhya Maharashtra

Abstract

Information in processed form, is often needed to meet the demands in agriculture, hydrology and other water-related human activities.  In this context, daily rainfall continue to be of prime importance since it is the daily rainfall which, when accumulated gives weekly, monthly or seasonal totals. This paper deals with some of the characteristic features of daily rainfall at nine selected stations in Madhya Maharashtra.  The study is based on daily rainfall data of June to September months for 10 years (1991-2000).

                Depending upon rainfall amounts (or lack of it), a day has been categorized as rainy day, drizzle day or dry day.  Making use of the concept of evapotranspiration, rainy day has been further divided into crop rainy day.   Distribution of these various classes of days, their contribution to monthly totals and relationship among them, have been obtained and discussed.  The rainy days have been used to obtain mean daily rainfall intensity and its association with monthly rainfall, examined through a series of regression equations.  Frequency of heavy falls i.e., rainfall exceeding 25 mm in a day have been determined and its contribution to monthly rainfall, evaluated.

                There seems to be a tendency for the rainy days and the rainfall to be below normal in recent years.  Perfectly dry weather could prevail nearly half of June and July months over the region.  Heavy rainfall contributes substantially to the monthly total.  During June and September mean daily rainfall intensity is perhaps weakly related with the monthly rainfall.