• In the next 50 years, a third of the world’s population could be living in areas as hot as the hottest parts of the Sahara now.
• Humans have adapted to live in a narrow band of environmental and climatic fluctuations, but temperature rises threaten this.
• Health, food security and economic growth would face huge challenges outside the temperature ranges we currently inhabit.

By 2070, one-third of people could be living in conditions that are outside humanity’s comfort zone. That’s the conclusion of a group of scientists from the US, China and Europe who have analysed rising global temperatures and compared them to average climatic conditions over the last 6,000 years.

Their research warns that unless decisive action is taken to reverse the damage done by greenhouse gases, billions of people could be living in what are “unliveable” circumstances.

Climate change-related rapid temperature rise combined with population growth means that about 30% of the world’s projected population will live in places […]