The heatwave affecting Europe these days would have been almost impossible to occur just 50 years ago, and the explanation is as clear as can be, say scientists: climate changes caused by human activity rapidly amplify the frequency and intensity of extreme phenomena.
The conclusion belongs to an analysis conducted by the World Weather Attribution (WWA) organization, cited by Euronews. Researchers say that the record temperatures this week are a new proof that global warming is accelerating and warn that similar episodes will become increasingly frequent.
A heatwave that, in 1976, could hardly exist
Europe is going through one of the most severe heatwaves in recent years. France recorded its hottest day in the history of meteorological measurements, while the United Kingdom experienced its hottest June day ever, with 36.1 degrees Celsius. Over the weekend, meteorologists estimate temperatures up to 41 degrees in some regions of Hungary, Bulgaria, and the Czech Republic.
According to the WWA analysis, the maximum and minimum temperatures recorded during this episode would have been "almost impossible" to reach in the climate of 1976, that is, five decades ago.
Furthermore, if a similar heatwave had occurred under the climate conditions of that time, it would have been about 3.5 degrees Celsius cooler than the current one.
The explanation lies in both the atmospheric configuration – a persistent high-pressure system that blocked hot air masses above the continent and brought warm air from the Sahara – and global warming, which amplifies the effects of these phenomena.
"Science is clear about how climate change exacerbates heatwaves. Continuous emissions of fossil fuels are directly responsible for the disruptions people are experiencing this week in their homes, schools, and workplaces," said Theodore Keeping, a researcher at Imperial College London.
He warns that the pace of changes is alarming: Europe is setting temperature records at increasingly shorter intervals, and this year the phenomenon has repeated in consecutive months.
Tropical nights have become 100 times more likely
The study also highlights another worrying trend: tropical nights, where the temperature does not drop below 20 degrees Celsius, are now about 100 times more likely than during the major European heatwave of 2003.
These nights pose a major health risk as the body fails to cool down and recover from the accumulated heat during the day. Research shows that high nighttime temperatures are associated with increased mortality, especially among the elderly and those with chronic conditions.
The WWA analysis shows that out of the 854 cities evaluated in 30 European countries, nearly half have exceeded or are on the verge of surpassing records for the end of June in terms of the Wet Bulb Globe Temperature (WBGT) index, used to measure the heat stress felt by the body.
A recent study published in the journal Nature estimates that in southern Spain, Italy, Greece, and Turkey, some regions will have up to 40 additional days per year with severe heat stress compared to the 1970s.
UN: "Climate change is getting out of control"
The executive secretary of the UN Framework Convention on Climate Change, Simon Stiell, says that the heatwave confirms what the scientific community has been warning about for years.
"Extreme heat breaks record after record in Europe, and science is very clear about the cause: climate change is getting out of control," he said.
According to the UN, the burning of fossil fuels – coal, oil, and natural gas – is responsible for about 68% of global greenhouse gas emissions and nearly 90% of carbon dioxide emissions.
Simon Stiell argues that the solutions are already known: accelerating the transition to clean energy, protecting forests, and investing in adaptation to climate change.
Researchers reject the El Niño theory
The authors of the analysis also say that the heatwave cannot be attributed to the natural phenomenon El Niño, as some media reports have suggested.
Although El Niño influences global temperatures, its effects are mainly felt in tropical regions, and any consequences for Europe usually occur in autumn and early winter, not in June.
"We, scientists, are starting to feel like we are repeating the same message year after year. Yes, this is climate change. Yes, we are causing it. No, it's not El Niño. Yes, we have the solutions. No, we are not implementing them fast enough," said Friederike Otto, a professor at Imperial College London.
She warns that the question is no longer whether climate change exists, but what kind of future societies desire and whether they are willing to take the necessary measures to ensure it.
G.P.