A study published Tuesday concluded that without climate change, the current heat waves in Europe and the United States would have been “virtually impossible.”
Over 50 degrees in Death Valley, US, a record high of 45.3°C in Catalonia [Espanha]over 43°C in Phoenix [EUA] in the past 24 days: Without climate change, these heat waves would have been “practically impossible” in Europe and the United States, according to the World Weather Attribution (WWA) scientific network.
The WWA, which evaluates the relationship between extreme weather events and climate change, also believed that climate change made China’s heat wave “at least 50 times more likely.”
These heat waves “are no longer exceptional events” and the ones that do occur “will be even more intense and frequent as emissions [de gases com efeito de estufa] are not rapidly reduced,’ the researchers concluded.
While natural phenomena, such as anticyclones and ‘El Niño’, can contribute to causing these heat waves, the increase “in global temperatures due to the burning of fossil fuels is the main reason why they are so severe,” the WWA points out.
To reach these conclusions, the study’s authors – seven scientists from the Netherlands, the United Kingdom and the United States – used historical meteorological data and climate models to compare the current climate and global warming of 1.2 degrees with what it was in the past.
These results were published without going through the lengthy process of a peer review, but combine methods already approved by peers.
The scientists paid special attention to the periods when the heat was “most dangerous,” i.e. July 12 to 18 in southern Europe, July 1 to 18 in the western United States, Texas and northern Mexico, and July 5 to 18 in central and eastern China.
Those responsible pointed out that global warming is exacerbating the intensity of temperatures: with global warming, heat waves in Europe are 2.5°C hotter, those in North America are 2°C warmer and those in China are 1°C warmer, according to the WWA.
According to NASA and the European Observatory Copernicus, this month is “expected to be the warmest July on record”.
“In the past, these events would have been anomalous, but in today’s climate they could happen about every 15 years in North America, every 10 years in southern Europe, and every five years in China,” explained Mariam Zachariah, a scientist at Imperial College London who contributed to the study, in a telephone briefing.
These heat waves “will become even more frequent and will occur every two or every five years” if global warming reaches 2°C, “which could happen in about 30 years unless all countries that have signed the Paris Agreement fully honor current commitments to rapidly reduce emissions,” he added.
This early summer “could become the norm (…) and even be considered cool if we don’t become carbon neutral,” underlined British climatologist Friederike Otto.
According to Otto, “the results of this attribution study are not a surprise. (…) From a scientific point of view it is even irritating, because it only confirms what we predicted. But what we did not foresee was how vulnerable we are to the effects of global warming. Because it kills people,” he stressed.
“However, these heat waves are not evidence of ‘runaway global warming’ or a ‘climate meltdown.’ We still have time” to reverse the situation, the scientist said.
“We urgently need to stop burning fossil fuels and work to reduce our vulnerabilities. If we don’t, tens of thousands of people will continue to die,” said Otto, who considers it “absolutely essential” that international legislation on fossil fuel phase-out is passed at the 28th UN Climate Change Conference (COP) in Dubai in November.
Source: DN
