Seasonal Patterns and Long-Term Intensification of Compound Dry-Hot Extremes (CDHE) Across Major Cities in India

This study presents a seasonal spatiotemporal analysis of Compound Dry-Hot Events across 24 Indian cities spanning diverse climatic zones during 1951–2023. Concurrent and sequential 3- and 5-day events were analysed using Innovative Trend Analysis and the Mann–Kendall test to assess trends in occurrence and persistence under varying severity thresholds, while seasonal Sen’s slope and MK tests evaluated trends in monthly averaged spatial extent. Results indicate a pronounced rise in moderate-intensity, short-duration events across India. The temporal trend indicates CDHE occurrence is increasing at a faster rate than persistence, and spatial extent diminishes with longer durations or lags. Southern Peninsular cities consistently emerge as hotspots across all seasons, while other regions display strong seasonal variability. Concurrent CDHEs show positive trends in occurrence, persistence, and spatial extent, whereas hot-on-dry events are strongly limited by lag effects. The findings highlight distinct city-level CDHE patterns and regional–seasonal contrasts across urban India.