Hot weather disruptions are projected to rise as decades pass -- they already have -- taking metropolitan areas dangerously past historic high temperatures, sometimes for days or weeks at a time.
A study of the U.K. this week in the Journal of Epidemiology and Community Health, sees a rising probability of dangerous heatwaves as the century progresses. Heat-related deaths could rise by more than 250 percent by mid-century, with some of the most dramatic increases occurring in London.
Researchers from two British institutions studied the relationship between weather and mortality between 1993 and 2006, then combined their findings with 21st century warming projections. The rising temperature and heightened variability, they conclude, "will be unprecedented since agricultural times, making it unlikely that future societal adaptation to hot weather will be as achievable as in the past.”
Heat-related deaths in London are projected to increase 39 percent by the 2020s, to 6.1 deaths for every 100,000 people. The estimate increases to 11.3 by the 2050s and 17.5 in the 2080s (assuming London hasn't been evacuated by then to Norway or some kind of anti-heat syrum developed). Currently, about 2,000 people a year die from heat-related stress, and 41,000 from cold-related deaths.
There’s an upside to the coming heat bombs. Cold days were found to have a higher mortality rate than hot ones. The overall number of temperature-related deaths is projected to decline by the 2050s, as the increase in heat-stress deaths is offset by fewer lives lost in cold weather.
The study emphasizes that its projections occur "in the absence of any adaptation of the population" -- an assumption already wearing away, as cities and companies reinvent themselves for a changing world.
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