10 May, 2021

Deadly Heat Stress to Become Commonplace Across South Asia Already at 1.5°C of Global Warming

Authors

Fahad Saeed, Carl-Friedrich Schleussner, Moetasim Ashfaq

The study calculates the impact of an additional half degree of warming between 1.5°C and 2°C for hundreds of millions of people in South Asia, a region that is already experiencing lethal heat events. It finds that governments can virtually halve exposure to potentially lethal temperatures if global efforts to limit warming to 1.5°C are successful.

Wet bulb temperature thresholds of 32°C and 35°C are respectively considered as the upper limits of labor productivity and human survivability. Some areas in South Asia have already witnessed such heat stress conditions and their occurrences with larger geographical footprint are projected to become commonplace even at the 1.5°C Paris Agreement temperature. Risks at 2°C warming would be about twice as high compared to 1.5°C. Presently, the world is already 1°C warmer than the pre-industrial period, and it may reach 1.5°C level by 2040, reflecting an imminent need for out of the box adaptation measures in SA

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