Observational Evidence of Increasing Compound Tropical Cyclone‐Moist Heat Extremes in India

Abstract

Moist heat stress can lead to the inability of the human body to cool itself due to the impact of high temperature and humidity. The co‐occurrence of tropical cyclones (TCs) and moist heat stress has considerable implications for India's dense population and infrastructure. However, the crucial linkage between TCs and moist heat extremes remains unrecognized. We used the cyclone eAtlas and ERA5 reanalysis to examine the temporally compounding TC and moist heat extremes over India from 1980 to 2021. We find that TC‐Heat stress events in India have increased recently, which can be attributed to the high‐intensity TCs originating from the Arabian Sea. The risk of TC‐Heat stress events is higher (than in other parts of the world) in India due to an overlap of peak moist heat and TCs occurrence during the pre‐monsoon (April–June) season. Landfalling TCs alter the thermodynamic environment causing the moist heat to peak over the region with increased frequency and intensity. The direct and compounded influence of TCs on moist heat can have substantial implications.

Joint probabilistic behaviour of climate extremes over the Godavari River basin, India

“…For the historical period, the values of T 10 CDD,CWD and T 10 R95,R5 (JRP values ranging from 12 to 114 years) are lower in the grids of the central and downstream regions of the basin implying possibility of occurrence of 'droughts and floods' and intense 'dry and wet spells' in a single year. The observed changes (increased frequency) in the compound extremes (e.g., dry and hot extremes) during historical period in this study are in agreement with the previous findings (Dash and Maity, 2021;Guntu and Agarwal, 2021;Rajeev and Mishra, 2022).…”

“…For example, extreme temperature indices are associated with El Nino conditions, which can cause changes in joint extremes (Rusticucci et al, 2017). Changes in the compound dry and hot extremes over southern peninsular regions in India are associated with land–atmosphere coupling (Rajeev and Mishra, 2022). However, a detailed investigation of the physical mechanisms associated with the changes in the joint occurrence of rainfall and temperature extremes is beyond the scope of the present study.…”

Climate change dominates the increasing exposure of global population to compound heatwave and humidity extremes in the future

“…However, heatwave events can affect outdoor work and increase stress on power systems. In these areas, future studies should pay more attention to the impact of heatwaves on infrastructure and the economy (Rajeev and Mishra, 2022;Yin et al, 2023).…”

“…Research on extreme events has received significant attention in recent years due to their severe impact on human societies and economies (Alexander et al, 2006;Cook et al, 2020;. Compound events can be defined as two or more extreme events occurring simultaneously or successively, such as compound flood and hot events (Gu et al, 2022), combination of tropical cyclones and moist heat (Rajeev & Mishra, 2022), compound drought and heatwave events and compound heatwave and humidity (IPCC, 2021;Coffel et al, 2018). Compared with single extreme events, compound extremes may have more devastating effects on water resources management, human society and ecosystem (Ridder et al, 2020;Rogers et al, 2021;Zscheischler et al, 2018;Tripathy et al, 2023).…”

Observational Evidence Reveals Compound Humid Heat Stress‐Extreme Rainfall Hotspots in India

“…In addition, higher surface temperatures and increasing downwelling infrared radiation due to anthropogenic climate change enhances surface evaporation, which increases the atmospheric moisture content and leads to extreme rainfall (Roderick et al., 2019; Trenberth, 1999). There is growing evidence of heavy rainfall following humid heatwaves both locally (Feng et al., 2022; Rajeev & Mishra, 2022; S. S.‐Y. Wang et al., 2019) and worldwide (Sauter et al., 2023; Yin et al., 2022).…”