Chained Heatwaves: Understanding the Domino Effect in South Asia

A recent study reveals that heatwaves can set the stage for successive intense heat events. Researchers from IIT Bombay and Germany explored the back-to-back heatwaves in South Asia during March-April 2022, highlighting how initial heatwaves deplete soil moisture, intensifying subsequent heatwaves through complex atmospheric processes.

According to a groundbreaking study, heatwaves can create environmental conditions that increase the likelihood of subsequent heat events. Conducted by researchers from IIT Bombay and Johannes Gutenberg-University Mainz, the investigation focused on the extreme heatwaves that plagued South Asia, particularly India and Pakistan, in March and April of 2022.

During these months, temperatures soared to levels well above the seasonal average, a situation that extended into May. The research, published in the Journal of Geophysical Research: Atmospheres, finds that each heatwave was driven by distinct atmospheric processes. The March heatwave, sparked by large-scale atmospheric Rossby waves, dried out soil, which exacerbated the April heatwave by transforming solar energy into more surface heating.

The team emphasized the concerning pattern where dryness from initial heatwaves leads to more severe subsequent events. They warn that with climate change making such events more common, understanding these patterns is vital for better prediction and preparation in South Asia, with significant implications for both local and global environmental policy.

(With inputs from agencies.)