Dozens of dead. Tens of thousands displaced. Vast areas devastated by water or flames. This is what is happening this week on both sides of Europe. While floods inundate the center and east of the continent, fires are burning Portugal. Behind them, record torrential rains and environmental conditions of maximum fire risk. Both extremes are fueled by global warming.
The climatic grip that is gripping the continent from both sides is made up of, on the one hand, record temperatures in the Black Sea and the Mediterranean Sea – which fuelled the precipitation from Storm Boris; and on the other, heat, drought and wind that have raised the fire-weather index to levels rarely seen in Portugal.
High sea temperatures: fuel for rain
In the strip extending from Romania to Poland, through Hungary, Slovakia, Austria, the Czech Republic and Germany, the torrential rains of storm Boris concentrated in four days five times more water than the average for September. The large rivers of the European plains overflowed their banks.
The floods have killed more than 22 people. The mayor of Wroclaw, Poland’s third largest city on the Oder River, has prepared a plan to evacuate the entire population, more than half a million people. The International Federation of Red Cross and Red Crescent Societies said the emergency “could be the worst since 2002.”
Today, the Black Sea is very warm: with areas where the water is more than 4ºC above average and others with even 5 or 6 degrees more, as confirmed by the National Meteorological Agency. At the same time, the Eastern Mediterranean shows values between 2 and 3 degrees above the average for this time of year. It varies between 26ºC and 28ºC. “There are even areas where the temperature exceeds 28ºC, which is the threshold required for a depression to be a hurricane,” explains Luis Bañón, meteorologist at AEMET.
The moisture needed for precipitation comes from the sea. The wind carries it across the sea surface. So the warmer the water, the warmer the air that comes out. And warmer air lets in more vapor, which leads to more precipitation.
Luis Banon
— AEMET Meteorologist
Bañón explains that “the moisture in the precipitation comes from the sea. The wind carries it to the surface of the sea. So the warmer the water, the warmer the air that comes out. And the warmer air lets in more vapor, which leads to more precipitation.”
The meteorologist adds that “the warm sea adds up, but the most decisive thing is that then there is a storm, that is, cold air so that this moisture load turns into rain.” In the case of Boris, the storm also remained blocked in the same area while it did not stop downloading.
The general relationship between extreme rainfall (which eventually leads to flooding and flooding) and climate change continues to strengthen. For every additional degree of global warming, “storms release between 15% and 21% more,” scientists from the Universities of Sydney, Exeter and Adelaide explain in a recent study. “A warmer atmosphere is able to hold more moisture,” they argued.
And they gave more insight into how global warming is fueling storms: “As water vapor condenses into droplets, it produces more heat that supercharges storms.” Spain’s records reflect this trend: climate change has quadrupled the intensity of torrential rains.
“24 very complicated hours”
While in this part of Europe the population is literally drowning, on the other side it is suffocating because of the smoke from the hundreds of thousands of trees burning in more than a hundred forest fires that have been ravaging the center and north of Portugal for days. Seven people have died since Sunday and the government will maintain the state of alert until at least Friday. The smoke from the fires reaches Galicia and obscures the light of the Sun.
“The next 24 hours will be very complicated,” warned the Portuguese Civil Protection on Wednesday.
The information we have indicates that we were very close to the maximum risk of fires in several districts of Portugal, something that had not been verified before.
Joaquim Sande Silva
— Specialist in fire ecology at the Polytechnic Institute of Coimbra
The professor specializing in fire ecology at the Polytechnic Institute of Coimbra, Joaquim Sande Silva, explains to elDiario.es that “the low humidity and the dryness of the vegetation have been combined with a strong wind and the carrying out of numerous risky activities.” reports Sofía Pérez Mendoza.
This expert, who participated in the independent commission that investigated the two major fires seven years ago on behalf of the Assembly of the Republic, admits that it is “difficult to link a single event with trends that are verified over the long term.” “However, the information we have indicates that we were very close to the maximum risk of fires in several districts of Portugal, something that had not been verified before,” he says.
The link between wildfires and climate change is also reinforced with each cycle of research. Increasing heat, the expansion of more severe and prolonged droughts – which dry out flora – and the atmosphere thirsty ““They have been a key factor in increasing the risk of wildfires,” the US Atmospheric Administration said.
In Spain, the index that measures the meteorological risk of fire has increased by 23% in 40 years: it implies high temperatures and little rain that influence the dryness of the plants that thus serve as fuel for the forests to burn.
Since the start of this series of fires in Portugal (there have been hundreds of outbreaks), some 70,000 hectares have burned and 29 people suspected of having participated in starting the fires have been arrested. The government has declared the municipalities affected by the flames a “catastrophic zone”.
