Rainfall trend of Akola station in Vidarbha using parametric and non-parametric test

Abstract

Global warming can affect land ecosystems especially water cycle. Rainfall is a key input in management of agriculture and irrigation projects and any change in this variable can influence on sustainable management of water resources and agriculture. The present study investigates the rainfall variation and trends in Akola station in Vidharbha using daily rainfall data for 47 year (1970-2016). Trend analysis was done by using Mann- Kendall test and Sen’s slope test. The results reveal that average annual rainfall of Akola was 796.65 mm which varied from ± 202.12 mm/year with 25.27 per cent coefficient of variation. The annual and seasonal rainfall and rainy days didn’t exhibit any statistical significant trend. Monthly rainfall and rainy days shows significant trends during month of August as decreasing (-2.95 mm/year) at 99% and July as increasing (0.08 mm/year) at 90% confidence level. Weekly rainfall showed trends during Standard Metrological Week (SMW) 30 as increasing (Qt = 0.97 mm/year) and 32 and 33 SMW as decreasing (Qt = -0.77 & Qt = 0.71 mm/year) and weekly rainy days shows trends for during SMW 26 as decreasing (-0.04 mm/year) and for SMW 30 as increasing (0.57 mm/year) for Akola station. These changes may further influence on water resource availability for agriculture in the region.