Analysis of Annual and Seasonal Rainfall of Different Districts of Odisha

Abstract

AbstractTemperature of the earth’s surface increased over the last few decades because of global warming which effected the hydrological cycle and patterns of precipitation across World. Precipitation is one of the important parameter of water cycle which affects the agriculture by influencing the availability of water resources. The trend as well as pattern of the rainfall disturb significantly because of the climatic variability. This study carried out for finding the decadal changes of seasonal rainfall (monsoon), annual rainfall, and also the seasonality index (SI) along with annual as well as seasonal trend analysis rainfall for all thirty districts of Odisha. Daily rainfall data of thirty districts over 30 (1990–2019) years were collected and converted to annual rainfall and seasonal rainfall (monsoon) data, and was used for the analysis. Decade wise, Angul, Balasore, Dhenkanal, Jagatsinghpur, Jajpur, Kendrapara, Khordha and Puri Districts experienced decrease in average annual rainfall whereas Nawarangpur and Nayagarh Districts detected with increase in average annual rainfall. Decade wise, decrease in average monsoon rainfall is observed for Bhadrak, Bolangir aand Dhenkanal districts where as increase of average monsoon rainfall is observed in Gajapati, Ganjam, Koraput and Nuapada Districts. SI value was found to be lowest (0.76) in Gajapati district whereas maximum value of 1.13 in Bargarh district. Mann–Kendall test was performed for the seasonal as well as monsoon rainfall trend analysis. Amongst all districts, Koraput district experienced significant increasing trend for the annual rainfall. Significant increasing trend of seasonal (monsoon) rainfall observed for Koraput and Gajapati districts. Districts experiencing decreasing trend are critical from water resource management and crop planning view for annual and monsoon rainfall respectively.KeywordsRainfallTrendSeasonality indexWater resources management