The human cost of the climate crisis will hit harder, wider and sooner than previously believed, according to a study that shows a billion people will either be displaced or forced to endure insufferable heat for every additional 1C rise in the global temperature.
In a worst-case scenario of accelerating emissions, areas currently home to a third of the world’s population will be as hot as the hottest parts of the Sahara within 50 years, the paper warns. Even in the most optimistic outlook, 1.2 billion people will fall outside the comfortable “climate niche” in which humans have thrived for at least 6,000 years.
The authors of the study said they were “floored” and “blown away” by the findings because they had not expected our species to be so vulnerable.
“The numbers are flabbergasting. I literally did a double take when I first saw them, ” Tim Lenton, of Exeter University, said. “I’ve previously studied climate tipping points, which are usually considered apocalyptic. But this hit home harder. This puts the threat in very human terms.”
The vast majority of humanity has always lived in regions where the average annual temperatures are around 6C (43F) to 28C (82F), which is ideal for human health and food production. But this sweet spot is shifting and shrinking as a result of manmade global heating, which drops more people into what the authors describe as “near unliveable” extremes.
The authors said their findings should spur policymakers to accelerate emission cuts and work together to cope with migration because each degree of warming that can be avoided will save a billion people from falling out of humanity’s climate niche.
Source: Guardian
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