’Near-unlivable’ heat for one-third of humans within 50 years if greenhouse gas emissions are not cut

Areas of the planet home to one-third of humans will become as hot as the hottest parts of the Sahara within 50 years, unless greenhouse gas emissions fall, according to research by scientists from China, USA and Europe published in the journal Proceedings of the National Academy of Sciences this week. The rapid heating would mean that 3.5 billion people would live outside the climate ‘niche’ in which humans have thrived for 6,000 years.

Published as billions of people are locked down by the corona crisis, the findings are a stark warning that continued carbon emissions would put the world at increasing risk of further unprecedented crises, the international research team of archaeologists, ecologists, and climate scientists concludes.

Temperatures are projected to increase rapidly as a result of human greenhouse gas emissions. Under a scenario in which emissions continue to increase unabated, temperature experienced by the average person will have risen 7.5°C by 2070. That is more than the expected global average temperature rise of slightly over 3°C because land will warm much faster than the ocean and also because population growth is biased towards already hot places.

Wur