Guwahati: Northeast India is experiencing a rise in both short-duration, heavy rainfall events and prolonged dry spells, pointing to increasing climate variability in the region, according to a study published in the “International Journal of Climatology”.The study, titled “Evolution of Climate Extremes Over the Indian Subcontinent Using a Revised CEI”, analysed daily rainfall and temperature observations from India Meteorological Department between 1971 and 2022.The northeast was the only region in which the study found a clear, statistically significant increase in extreme one-day rainfall. The authors linked the trend to a warming Bay of Bengal, greater atmospheric moisture and the region’s complex terrain. At the same time, dry spells and drought were becoming more frequent.“The northeast is the one region swinging between extremes — heavier single-day downpours on one side and longer dry spells on the other. That combination points to a more unstable monsoon, and it calls for both flood preparedness and drought planning,” said M Rajeevan, a co-author of the study.The authors said the study combined seven separate hazards — including daytime heat, humid heat, heatwave severity and drought — into a single India Climate Extremes Index. The analysis was based on 52 years of IMD observations, with trends tested using the Mann-Kendall method.“The region is the only part of the country where we see a clear rise in short, intense one-day rainfall, even as dry spells lengthen. It stands apart from the heat-and-drought story that dominates the rest of India,” said Thota Mohan, the lead author of the study.The researchers called for finer-scale monitoring and region-specific adaptation strategies to address changing climate extremes. The findings highlight the importance of considering both heavy rainfall and dry spells in climate planning, rather than viewing the region simply as becoming wetter or drier.
