Spain is experiencing the first heat wave of the year, an episode that, from this Wednesday, affects almost the entire Peninsula – except the Cantabrian – and the Balearic Islands and in which it is expected to reach a maximum 45 degrees in the Guadalquivir valley, as well like torrid nights — from a minimum of 26 to 28 degrees — in various parts of the country. The high temperatures come three days after the forceful report of the IPCC, the UN panel of experts on climate change, which scientifically demonstrated that human action “has warmed the atmosphere, the ocean and the land” and has caused profound changes in the climate, among them, the rise in temperatures and the multiplication of this type of extreme phenomena. Although the attribution of a specific episode to climate change is made later, Rubén del Campo, spokesman for the State Meteorological Agency (AEMET), confirms that Spain has doubled heat waves in just a decade. “Human action is increasing heat waves in frequency and intensity. In 30 years, a summer like the ones today will be considered a cold summer ”, he explains.
According to the state agency, the thermometers will mark between 5 and 10 degrees above the average values of this time. In some points of the northeast and the southern half, more than 10 degrees above the average values will be registered. The agency predicts that the presence of airborne dust, which sometimes acts as an umbrella and helps clouds form, can alter forecasts. In any case, daytime and nighttime temperatures will be “very high, extreme, unusual for this time of year” in most of the Peninsula.
Heat waves require meeting three criteria regarding temperatures: they have to be very high, that is, 5% warmer than those that usually exist in summer; they have to affect a large part of the territory —at least 10% of the almost 800 weather stations that the state agency has—, and they must last at least three days. “In this case we know that the characteristics will be fulfilled a priori, that’s why we can declare it now ”, says Del Campo. “Other times we only know that it was a heat wave after analyzing the data afterwards,” he adds.
These types of episodes have doubled in just 10 years, according to data from the AEMET. Between the 1980s and the 2000s there were between 10 and 12 heat waves per decade (almost one per year); in the last decade (2010-2020) there have been 24. Del Campo sums it up like this: “Heat waves have doubled in a decade and the trend is that they are becoming more frequent and more intense. And in parallel, heat records are much more frequent than they would be without climate change ”.
The climatologist Dominic Royé, a professor at the University of Santiago de Compostela, has studied the Spanish heat waves and has made a future projection, published in the latest issue of the scientific journal Atmospheric Research. “In the three decades between 1971 and 2000, there was an average of 21 days of heat waves in Spain per year,” says Royé. “According to our projection, in 2050 there will be at least 41 days of these characteristics per year, while in the worst emissions scenario we will reach 50 days with extreme heat.” The professor, who prepared his work together with Nieves Lorenzo and Alejandro Díaz-Poso, provides another piece of information: if in the three decades at the end of the 20th century each of these phenomena affected, on average, 16% of the territory of the Peninsula, in 2050 it will be between 26% and 32%.
“An exceptional wave”
Royé considers that the current episode “is an exceptional wave because it is going to have very high temperatures both in the maximum and in the minimum. And the affected population is also very large, only the Cantabrian coast and Galicia will remain outside ”. In any case, “it will be necessary to see later in what terms the wave is situated, because for now it is a prediction that can change with observation, it remains to be seen if particles from the Sahara arrive that do not allow all the radiation to enter, which would prevent the maximum temperatures foreseen are reached ”.
Hicham Acheback, from the IS Global Climate and Health group, participated in a study, published in The Lancet on July 1 of this year, in which it states that deaths from heat and its effects amounted to 3,669 people per year in the period 1998-2012 in Spain. Based on these data and taking into account the increase in temperature, the report predicts that deaths in Spain could reach 14,531 per year in the period 2035-2064 (in the worst case scenario, without reducing greenhouse gas emissions); while from 2070-2099 there would be 30,443 deaths (also in the worst scenario). In any case, the study does not take into account the adaptability of Spaniards. “In the last four decades, there has been an improvement in living standards and more access to air conditioning and heating, so that much of the population is better prepared for these temperatures,” admits Acheback.
The IS Global expert explains that the increase in temperature is directly related to the increase in mortality. “These temperatures trigger processes in our body that translate into a growth in hospital admissions for cardiovascular and respiratory causes, as well as more deaths. The most affected are the elderly, who are the most vulnerable ”. To minimize this impact, and after a severe heat wave in 2003, Spain launched an extreme heat alert system. “The system basically tries to raise awareness among the population, it asks them not to go out on the streets in the hours when there is more sun, to drink a lot of water … These are basic things, but very effective,” says Acheback. Some countries are setting up refrigeration centers, located in pavilions or municipal facilities, so that those who do not have air conditioning can take refuge there in the hottest moments.
The AEMET spokesperson also points out that these phenomena “greatly increase the risk of fires.” In fact, the General Directorate of Civil Protection and Emergencies of the Ministry of the Interior has recommended that citizens “take extreme precautions” for this cause, given that the country is at extreme risk of fires. Catalonia has gone further and has prohibited activities such as youth camps in the natural environment and the use of agricultural machinery between 10:00 and 20:00 in the 279 municipalities, as well as in various natural areas. From January 1 to July 25, 2021, 1,959 fires have occurred in Spain, which have burned 37,535.9 hectares of forest area, according to the latest data from the Ministry for Ecological Transition. Although this is much more than last year at this time (21,132 hectares), it must be taken into account that the 2020 figures were especially good due to the effect of the more severe confinements and movement restrictions due to the pandemic.