Long-Term Analysis of Minimum Temperature Trends in Nagpur District of Maharashtra, India

Abstract

This study analysed minimum temperature trends in Nagpur, India, from 1985 to 2024, based on daily data from the District Agromet Unit of ICAR - Central Institute for Cotton Research. Temperature data were aggregated into monthly, seasonal, and annual values using Weather Cock15 software, with a focus on evaluating long-term and decadal trends. During 1985-1994, the annual minimum temperature showed a slight, non-significant decrease of 0.014°C, with small declines in both the Southwest (SW) and Northeast (NE) Monsoon seasons, as well as in winter. The most notable change was a 0.133°C decrease in September, which was significant at the 90% confidence level. In the subsequent decade, from 1995-2004, the annual minimum temperature increased by 0.050°C, though this was non-significant. Winter and summer temperatures both showed non-significant increases of 0.200°C, while April stood out with a significant increase of 0.300°C at the 95% confidence level. During, 2005-2014, the annual minimum temperature decreased slightly by 0.017°C, with the NE Monsoon showing a minor decline. December recorded a significant decrease of 0.250°C at the 95% confidence level. However, in the most recent decade (2015-2024), a clear warming trend emerged, with the annual minimum temperature rising by 0.167°C, significant at the 90% confidence level. The NE Monsoon showed a substantial increase of 0.320°C, and both January and December experienced significant increases, with December showing the largest rise of 0.500°C, significant at the 99% confidence level.