What extreme weather events will increase with global warming?
By disrupting a number of atmospheric flows and accelerating certain natural processes, global warming caused by the increase in the amount of greenhouse gases in the atmosphere as a result of human activity will lead to the increase and intensification of certain meteorological phenomena. mechanism already observed.
“A shift in the intensity and frequency of some extreme climate and weather events has been detected during periods of about 0.5°C global warming.”The Intergovernmental Panel on Climate Change (IPCC) noted in its 2019 report.
But what events are we talking about exactly? We take part.
More frequent and intense heat waves and heat waves
The most immediate and also the most visible consequence of global warming will be the increase and intensification of heat waves and other heat waves. “The increase in the number of heat waves is clearly linked to global warming”explains the Commissioner for Atomic Energy and Alternative Energies, which is particularly committed to climate issues.
Also read: Frequency, relation to global warming… 4 questions about heat waves
“The warmer the climate, the more frequent extreme heat episodes will occur and the longer and more intense the heat waves will be.”concluded last August in an interview with IPCC Working Group 1 Vice-Chair Valerie Masson-Delmotte. Western France . These high heat episodes can also occur earlier and earlier (toward the end of spring) or later and later (early fall).
More severe droughts and in more areas
Due to this global warming and increased number of hot episodes, droughts will also become more frequent and intense in the future.
“The risk of drought is expected to worsen, with faster and more intense worsening of drought associated with reduced precipitation and increased evaporation. [processus par lequel l’eau liquide terrestre est renvoyée dans l’atmosphère environnant sous forme gazeuse] lands”, The impact of global warming is determined by the National Observatory, which studies the case of France.
The same observation can be made on a global scale because, as the World Meteorological Organization points out, “Increasing global warming is also expected to increase the area of land affected by more frequent and severe droughts.”.
The risk of forest fires is increasing
All of these meteorological conditions will lead to more frequent and severe forest fires.
“Increasing episodes of both warm, dry and windy combinations that favor fires are also a key trend associated with global warming.”Valerie Masson-Delmotte of the IPCC explains.
“In some parts of the world, the risk of forest fires may increase due to increased temperatures and increased drought conditions.”particularly referring Onerc is abundant “Southern Europe” and the Mediterranean Sea.
More and stronger extreme rainfall events
Episodes of heavy rain in certain parts of the Mediterranean coast, such as France, will also become more frequent due to global warming.
“Warming also leads to an intensification of the water cycle with an increase in extreme precipitation events.”Valerie Masson-Delmotte explains.
“IPCC shows increased risk of extreme precipitation in 21e century was probable, and an equivalent result was determined for France.It is rich in energy.
In turn, the World Meteorological Organization reminds this “Extreme daily precipitation will intensify by about 7% for each additional global warming”.
More frequent sea floods
Rising sea levels due to global warming will cause more frequent flooding along certain parts of the coast.
“Warming is also accompanied by more insidious changes, such as accelerating sea level rise. This leads to increased chronic flooding at high tide.Valerie Masson-Delmotte explains.
Stronger thunderstorms, but not necessarily more
At present, it is impossible to say that global warming will cause more storms.
“As for the potential increase in the risk of storms due to global warming, there is no scientific evidence today that would allow us to make that conclusion.”said recently Western France Virginie Schwarz, CEO of Météo France.
However, if they do not increase in number in the future, this could mean that they become more intense, and that rising temperatures will lead to more water vapor in the atmosphere and, therefore, more precipitation.
There are no clues as to the evolution of storms
According to scientists, it is impossible to say that global warming will affect the formation of storms.
“Current research does not allow us to highlight a significant future trend in the evolution of severe wind risk associated with storms”, the National Observatory reports on the effects of global warming. An observation transmitted by Météo France, among others.
Hurricanes are not necessarily more numerous, but often more intense
If we move away from our latitudes and examine cyclones, typhoons and other hurricanes, the observation is the same. “Global Warming, a priorihas no effect on the activation of cyclones”The Atomic Energy Commission explains. “We also note that the number of extratropical storms and tropical cyclones has not increased in recent decades. »
Nevertheless, as with storms, if there is no indication that cyclonic systems will multiply in the future, each one should carry more precipitation than before due to the acceleration of the warming-related water cycle.
