VISHWANATH AND G.V. VENKATARAMANA
Abstract
An attempt was made to study the five year wise rainfall trends of Kalayan Karnataka. The study period spans for a period of 50 years from 1971-2020 which was divided into ten periods comprising each 5-year moving average to detect long term trends and further a linear tend was added as parametric test. Long term changes in rainfall characteristics were determined by both parametric and non-parametric tests. The analysis revealed that the period from 1991-1995 was found to be highest mean rainfall receiving period for the Bidar (1078.9 mm), Kalaburgi (976.7 mm) districts whereas for the Yadgir (1171.1mm) district it was from 1986-1990. However for Raichur (875.5 mm) and Koppal (670.7 mm) districts the period from 2001- 2005 was found to be highest mean rainfall receiving period whereas 1971-1975 was found to be for Ballari (705.7 mm) district. The highest CV was recorded during the period from 1981-1985, 1976-1980, 1976-1980, 2016-2020, 1976-1980 and 2006-2010 from Bidar (34.5%), Kalaburgi (36.8%), Yadgir (43.3%), Raichur (39.7%), Koppal (30.9%) and Ballari (30.8%) respectively indicating higher variability and lesser dependability. Senâs slope estimator showed that there is a positive trend for the Bidar, Raichur and Koppal rainfall pattern. However, Kalaburagi, Yadgir and Ballari exhibited a decreasing trend.