Read the text below.
At the end of the century, more than two billion people will be living in countries where extreme heat becomes life-threatening according to researchers in Europe and China.
That is expected to be a fifth of the population according to their research just published.
The warning about life-threatening global warming says that extreme heat will make life unbearable for many in the Global South.
The authors of the report on global warming say evidence shows humans have historically flourished in regions where the temperature is around 13 degrees Celsius.
Monsoon areas in South Asia have also fared well peaking at around 27 degrees Celsius.
But the report says people living in areas outside of these favored climates are less likely to thrive.
Using previously published research, the report says human health declines for many reasons, such as poor agriculture, therefore poor diet and nutrition.
Extreme heat also leads to lost days of employment and poorer economic outcomes as well as having a direct effect on human health according to the report.
Countries in Europe will become drier too according to lead author Professor Tim Lenton from the University of Exeter.
He describes the areas that will survive well as a ‘niche’ zone.
The study calculates that by conservative projections the temperature will have reached 2.7 degrees Celsius above pre-industrial levels in the year 2100.
It says that means two billion people would be living in life-threatening climatic conditions.
According to Lenton, less than 1% of humanity currently lives in places of dangerous heat exposure, but the study shows climate change has already put 9% of the population – more than 600 million people – outside this favored ‘niche’ area.
Lenton believes it’s important not just to focus on the deaths that will occur because of extreme heat.
He believes it’s also important to focus on how efforts to hold down global temperatures now will save billions of lives in the future.
This article was provided by The Associated Press.