The UN on Tuesday called on the world to prepare for more intense heat waves, urging every individual to make their own “contest plans” to weather extreme temperatures day and night.
“These phenomena will continue to intensify and the world must prepare for more intense heat waves,” said John Nairn, expert with the United Nations World Meteorological Organization (WMO), during a press briefing. regular in Geneva.
“The recently declared El Niño phenomenon will only amplify the occurrence and intensity of extreme heat waves,” he said.
In North America, Asia, North Africa and the Mediterranean Basin, temperatures will exceed 40°C for several days this week.
“One of the notable phenomena we have observed is that the number of simultaneous heat waves in the Northern Hemisphere has increased sixfold since the 1980s. This trend shows no signs of diminishing,” noted Nairn. .
“I therefore fear that we are not at the end of our troubles”, he added, stressing that “it is everyone’s responsibility to have plans to fight against extreme heat”.
Greenhouse gases that trap heat are the cause of climate change, experts say.
Gases such as carbon dioxide, methane and nitrous oxide play a crucial role in preventing some of the solar radiation from being reflected back into space.
When this cycle is balanced, it keeps the planet at a livable temperature.
But an unsustainable increase in the amounts of greenhouse gases in the atmosphere means more heat is trapped there, creating not only global warming but also other climate anomalies.
On video | Northern Hemisphere suffocates at peak heat waves
Night temperatures
For heat waves, climate change is increasing their duration, intensity and also their geographic reach, say the scientists.
Asked what individuals could do on a personal basis to try to tackle climate change, Mr Nairn called for a fight against fossil fuels.
“I think the easiest thing is to electrify everything. It’s a simple message. It’s about stopping carbon-based fuels,” he said.
As thermometers exceed or approach records, the WMO calls on the international community not to focus its attention solely on maximum temperatures.
“It’s actually the nighttime temperature that poses the greatest health risk, especially to vulnerable populations,” Nairn said.
He explained that in many places where the maximum reaches or exceeds 40°C, the temperature remains close to these levels at midnight.
However, underlined the expert, “repeated high night temperatures are particularly dangerous for human health, because the body fails to recover”, which ” leads to increased cases of heart attacks and deaths “.
There is no universal definition of heat waves, which are established in relation to the average temperatures of each region of the world, the normals of which vary considerably.
But the WMO is developing “standardized terminology and definitions” for extreme heat, it said Tuesday: “Categorizing the intensity of heat waves will help standardize forecasts of impact and alerts worldwide. »
On video | The world must prepare for record temperatures caused by El Niño