Report: 22% of population to suffer under dangerous heat due to weak climate policies

Pictured: Drought in Karnataka, India

The Global Systems Institute at the University of Exeter has today (22 May) published a study assessing the impact of 2.7C of warming above pre-industrial levels on the global population. This level of warming is the level believed to be likely by 2100 if existing national climate commitments are delivered.

The conclusion is that, by 2100 at the latest, two billion people would be exposed to average temperatures of 29C or higher in a 2.7C pathway – up from just 60 million today.

And, in a trajectory where warming exceeds 3.6C, at least half of the population would be exposed. The researchers state that, with a majority of the population outside of a liveable climate, humanity would face an “existential risk” with global trade systems and efforts to keep the peace breaking down.

According to the Institute, there is still a “huge potential” to change course now, implementing “decisive” climate policies that limit warming to the Paris Agreement’s 1.5C trajectory.

In a 1.5C world, the paper states, only 5% of the population would be exposed to dangerously high average temperatures, compared with 22% in a 2.7C world. And every fraction of a degree matters.

Social inequalities

The researchers highlight in the report that extreme temperatures are not felt equally – developing and emerging economies in the Global South already are the most affected.

Of the 60 million people already affected by extreme heat, the biggest ‘hotspots’ are in Nigeria and India.

In a 2.7C world, more than 600 million people in India and a further 300 million in Nigeria would suffer extreme temperatures. The figures drop to 90 million and 40 million respectively in a 1.5C world.

Moreover, in a 2.7C world, large swathes of land in Brazil and Australia would become uninhabitable.

There are also warnings for cooler, wealthier countries such as those in Northern Europe. While they are not set to get dangerously hot, Professor Chi Xu said, the conditions they would face in a 2.7C+ world have not historically supported dense human populations.

The publication of the study comes shortly after the World Meteorological Organization (WMO) warned that global annual average temperatures will exceed the 1.5C goal of the Paris Agreement by 2027, bringing life-altering climate impacts at a quicker pace.

While the climb above 1.5C is likely to be temporary, caused in part by changing El Nino patterns, the WMO is warning of potentially frequent breaches in the future.

Nations will meet in New York this September for an emergency climate summit tabled by the UN. They have been asked to present new, credible plans ahead of the next UN climate COP, COP28, which will be hosted in Dubai this winter.