Scientists have warned that without reductions in planet-warming carbon emissions, blistering heat waves of the strength that now typically occur once every 20 years could happen annually on 60 per cent of the Earth’s land areas by 2075.
At the same time intense heat waves, defined as three exceptionally hot days in a row, will become far more extreme if greenhouse gas emissions continue unchecked.
“Imagine the hottest day that you can remember and instead of 42 degrees Celsius, it’s now 45°C,” said Dr Michael Wehner of the Lawrence Berkeley National Laboratory in the United States.
“That’s going to have a dangerous impact on the poor, the old and the very young, who are typically the ones dying in heat waves,” Dr Wehner added.
In 10 per cent of the world, they would be at least 5.0°C hotter, the researchers said.
Reuters reports in December, around 195 countries agreed a new United Nations sponsored deal to try to restrain the rise in global average temperatures to “well below” 2.0°C above pre-industrial levels.
The new research, part of a larger project to quantify how emission reductions could affect health, agriculture, hurricanes, sea level rise and drought, found that stringent mitigation measures could reduce heat waves significantly.
“The study shows that aggressive cuts in greenhouse gas emissions will translate into sizable benefits, starting in the middle of the century, for both the number and intensity of extreme heat events,” said Dr Claudia Tebaldi of the National Centre for Atmospheric Research, where the project is based.
“Even though heat waves are on the rise, we still have time to avoid a large portion of the impacts,” she added.
The study said that, even with strong action to curb climate change, nearly a fifth of global land areas would still suffer intense heat waves yearly in 2075.