A humid-heat event crosses survivability thresholds with mass casualties
CLI-02 · probability 45% (confidence 62%, ±12 pts) over 2026-2032 · horizon NEXT 3-5Y · domain climate. Probabilistic simulation, not advice.
The reading
2024 was the first calendar year above 1.5°C, and 35°C wet-bulb — the physiological limit where sweating stops working — has already been touched briefly in the Persian Gulf and Indus Valley. The lethal scenario is mundane: a week-long humid heat dome over a South Asian megacity coinciding with grid failure; Europe's 2022 summer killed 61,000+ with air conditioning and functioning infrastructure.
What would prove this wrong
This projection is WRONG if through 2032, no single heat event causes 10,000+ deaths within a two-week window, and no station sustains 33°C+ wet-bulb for over 6 daytime hours in a populated area.
Trigger events tracked
- Pre-monsoon heat dome over the Indus/Ganges basin coinciding with load-shedding season
- Persian Gulf humid-heat excursions lengthening beyond the brief 2015-2020 spikes
- An El Niño year stacking on the warming trend (the 2023-24 amplification pattern)
- Urban grid failure during peak heat — the multiplier that converts heat stress into mass mortality
Causal chain
Historical precedents
If it happens
Sources
Directly related seals
Subjects this belongs to
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