The tropics and much of the Northern Hemisphere are likely to experience an irreversible rise in summer temperatures within the next 20 to 60 years if atmospheric greenhouse gas concentrations continue to increase.

Scientists concluded that many tropical regions in Africa, Asia and South America could see “the permanent emergence of unprecedented summer heat” in the next two decades.

Middle latitudes of Europe, China and North America are likely to undergo extreme summer temperature shifts within 60 years.