We’ve already seen the impact of deadly, humid heat at far lower thresholds, especially among the elderly and infirm.

Two heat waves in India and Pakistan that hit 30 C TW in 2015 left more than 4,000 people dead.

And the 2003 heat wave that killed more than 50,000 people in western Europe registered wet-bulb temperatures only in the high 20s.

Blistering heat waves across the northern hemisphere in 2019 — the second warmest year on record for the planet — also caused a large number of excess deaths, but wetbulb data is still lacking.

Research from the Institute for Health Metrics and Evaluation reports just over 300,000 heat-related deaths worldwide from all causes in 2019.

Some 37 percent of heat-related deaths — just over 100,000 — can be blamed on global warming, according to researchers led by Antonio Gasparrini at the London School of Hygiene & Tropical Medicine.

In half-a-dozen countries — Brazil, Peru, Colombia, the Philippines, Kuwait and Guatemala — the percentage was 60 percent or more.

Most of these deaths were probably caused by heat stroke, heart attacks and dehydration from heavy sweating, and many could likely have been prevented.