BarcelonaJune was the warmest month on record, with temperatures four degrees above the 1991-2020 climate average, surpassing the previous record, set in June 2023. Nights reached 30°C in the Catalan capital.
These data suggest that what was announced just a month ago by the World Meteorological Organization (WMO), which published a report with significant participation from the Barcelona Supercomputing Center (BSC-CNS), stating that June 20 will be outdated, will come to pass. In fact, the study warned that global temperatures would continue to rise in response to greenhouse gas emissions, which, despite numerous summits and international agreements, have not decreased. temperature that we have been seeing in the last three years," explains Toni Barrera Escoda, a technician from the Meteocat climate change team, to ARA. What happens is that, this expert points out, dejected, "the models did not predict these increases until the middle of the century." Therefore, because of this advance, something is "there is pre".
Barcelona, at 50 °C?
All models converge on an unflattering scenario on a global scale, and more specifically in the Mediterranean, which has become a hotspot for the climate crisis. In this scenario, Catalonia faces temperatures that could reach 50°C in inland areas, such as Terres de l'Ebre and Ponent, and exceed 40°C during the day in Barcelona.
To prepare the city for this climate emergency, Barcelona City Council recently presented the 2025-2035 Heat Plan with nearly 40 measures, including a simulation to assess the Catalan capital's capacity to respond to 50°C in two years, as this temperature is not expected to be reached in 2003.
"Why prepare for temperatures of 50°C when even 10°C or 15°C less will put us in extremely dangerous conditions due to thermal stress?" asks Markus Donat, an Icrea researcher and co-director of the BSC-NS climate change and variability research group. "In Barcelona, temperatures of 35°C due to humidity are already quite unbearable," he emphasizes, adding that "with Barcelona's climate, it's not plausible in any scenario, no matter how pessimistic, that we'll reach 50°C, at least not in this lifetime." Because that would mean that in the rest of Catalonia we would be around 60°C or more. "Life wouldn't be possible under these conditions," he concludes.
The climate extremes analysis models developed by this research center, which are used by all the models used in the United Nations IPCC report, show that for every degree of global warming, climate extremes in the Mediterranean region will increase by two degrees. The results are consistent with those of Meteocat. "We are very close to a scenario in which Barcelona will reach 40°C, we don't know if it will be this year or next, but it will happen before 2030 and by the end of the century we could have daytime temperatures of up to 45°C in situations like the current one, where sea breezes are inhibited by an anticyclonic situation. If the breeze doesn't come in, the city starts to heat up.
The greatest impact of this increase in temperature will occur, above all, at night in the Catalan capital, precisely because of the effect of the sea, where the so-called red-hot nights, with 30°C, are likely to set in.
White roofs, green areas
The Institute of Environmental Science and Technology (ICTA-UAB) has carried out a project for the Barcelona Metropolitan Area to assess which strategies would be most effective in reducing heat in the city during recent heat waves. They used a high-resolution meteorological model that captures the urban morphology and soil type of the entire metropolitan area, taking into account the heat island effect and radiation absorption by urban architectural materials, among other factors. They analyzed a scenario in which painting at least 70% of urban roofs white—which, instead of absorbing solar radiation, would reflect it, says Sergi Ventura, a postdoctoral researcher at ICTA—would lower temperatures by 2.2 local degrees.
Green roofs with Mediterranean shrub vegetation would also be effective, although less so, with reductions of up to half a degree. What studies do show works is removing asphalt and cement, increasing the number of hectares dedicated to green areas. By implementing 255 hectares of green areas as proposed in Barcelona's Urban Master Plan, a reduction of 1.70 degrees Celsius during the day and 1.24 degrees Celsius at night would be achieved. However, the best solution was to "combine white roofs and new green areas with high irrigation, which is a limitation due to the Mediterranean climate, subject to recurring periods of drought. This achieved reductions of up to 4.73 degrees Celsius," explains Ventura.
Furthermore, as numerous scientific studies have already demonstrated, green spaces in the city have beneficial effects on the physical and mental health of citizens and on biodiversity. "These green islands function as islands of coolness, as opposed to islands of heat," says Barrera Escoda. Most of the materials used in the city accumulate radiation during the day and expel it at night, which further heats the air, which further heats the materials. And so it is, in a vicious cycle that worsens especially at night.
However, in the latest study these researchers have just published, they have found that, when they apply "realistic" strategies (with irrigation and vegetation types more typical of the Mediterranean), "the reductions, despite being significant, do not compensate for the temperature increase expected due to global warming towards the end." Even so, the most vulnerable areas of the city, with lower incomes and higher population densities, would be the most benefited.
A vulnerability index
Together with Barcelona City Council and the Polytechnic University of Catalonia (UPC), Ecoserveis is developing a map of the Catalan capital using various indicators, ranging from demographics to housing quality and energy consumption. The goal is to create a vulnerability index on a building-by-building basis to measure the different impacts by neighborhood, since rising temperatures also have a different impact depending on the postal code. Living in Collserola is not the same as living in Poblenou, due to the geographical location and the quality of the housing.
Joana Mundó, co-director of Ecoserveis, points out that "the climate-vulnerable population lives in poorly insulated homes and cannot invest in more efficient appliances. They end up paying much more in energy over the year," she says. Air conditioning systems such as geothermal energy, with less climate impact, are also used.
More climate shelters
In addition to regreening and renaturalizing cities, it's necessary to implement more climate shelters and design them for vulnerable groups, believes Joana Mundó, energy expert and co-director of Ecoserveis, a non-profit consulting firm specializing in social and energy issues. "For example, taking a baby to a library as a climate shelter isn't viable, because when they cry they'll surely upset everyone, not to mention the fact that many are locked up in August," she adds.
The experts consulted by ARA insist that there is no alternative way to adapt cities to a scenario where the climate crisis will exacerbate extreme events, and we must also begin to adapt our behavior. We will have to change our habits, as in other parts of the world, modifying work and recreation schedules. In regions like northern Mexico, people spend their time on the streets at night, while during the day they don't leave their homes.
In the end, however, Barrera-Escoda warns, the "real" solution involves changing our consumption model as a society, because the current one is "totally unsustainable." "We must consume less," he warns, "right now, we need a lot of energy for our daily lives." He also adds that "although it may seem obvious, don't vote for political options that go against scientific evidence on the climate crisis, but rather for those that are committed to implementing solutions now," Donat emphasizes. There are examples. Paris, Medellín, Singapore... and Barcelona?
