Mexico City /
Recently some regions of Valencia, Spainexperienced in a single day the rains that would be expected in an entire year. The towns of Turis, chiva and Buñolrecorded more than 400 millimeters of precipitation, so the State Meteorological Agency (AEMET) declared a red alert in the area on the night of October 29.
Due to severe storms, at least 95 people have lost their lives. Thousands more were left without electricity and mobility: roads were closed and rail service in the region was suspended. Meanwhile, the authorities are deploying measures to serve the regions devastated by the water.
accompanied by waterspouts and powerful storms, DANApopularly known as ‘cold drop’, has been blamed for the damage. Given the magnitude it has reached, it is considered one of the most serious natural disasters of the last 75 years in Spain.
What is DANA?
The Isolated Depression at High Levelsbetter known as DANAcan be understood as an air mass where the pressure is lower, some meteorologists describe it as a “cold air pocket.”
It is isolated and made up of air of polar or subtropical origin that is located in high areas of the atmosphere.
Its formation “can unite all the necessary ingredients to generate the feared torrential rains”, however, and as the AEMET emphasizes, are not synonymous with catastrophic, intense or damaging stormsIn fact, they are just one of many systems with the ability to bring precipitation.
If everything continues as the weather models predict over the next 5 days, this DANA, due to its characteristics and behavior, has a lot of potential to enter the group of high impact ones.
Of those that can, they will be remembered on the Mediterranean side. pic.twitter.com/oT8vcmCPYV
— Dr JJ González Alemán (@glezjuanje) October 25, 2024
What could explain his strength?
Although the phenomenon is common in the Mediterranean area, especially between June and October, some experts had noticed favorable conditions that could turn the DANA in a more severe phenomenon than usual.
“If everything continues as the meteorological models predict during the next 5 days, this DANA, due to its characteristics and behavior, has a lot of potential to enter the group of high impact ones. “One of those that will be remembered on the Mediterranean side,” he wrote. Juan Jesús González AlemánAEMET researcher, in his account x last October 25.
Apparently, the forecast came true: rains hit part of Valencia on October 29. That same day, early in the morning, the AEMET declared a red alert for the community.
Associating a particular event like this with climate change requires pertinent studies, so it is too early to declare a direct relationship between what the region experienced and global warming, as pointed out by various experts consulted by Science Middle Center Spainan independent office promoted by the Spanish Foundation for Science and Technology.
However, this same group of scientists agrees that there are some conditions that could have favored the strengthening of DANA.
María José Sanz, director of the Basque Research Center on Climate Changeadds that, although “the attributions are complicated”, currently a large amount of humidity has been recorded in the atmosphere due to the high temperatures of the ocean.
This factor can encourage severe weather conditions, for example, it has been related to the rapid intensification of hurricanes in the Peaceful and the Atlantic. Although it has to be analyzed whether the heat in the sea influenced the DANAthere is a possibility that it was an important factor in the formation of the ‘perfect storm’.
“The storms have developed as a result of colder air passing over the warm Mediterranean Sea, creating atmospheric instability and bringing torrential rains. These types of storms can develop quickly and with relatively short notice,” he adds. Jess NeumannAssociate Professor of Hydrology at the University of Reading.
Furthermore, we now know that global warming has the potential to cause more severe and frequent rainfall, as Ernesto Rodríguez Camino, a member of the Spanish Meteorological Association.
In fact, some studies have begun to explore the possible implications of this trend in some regions, for example, in 2023 a group of researchers analyzed the possible scenarios for the city of Alicante, Spain.
“Current calculations and future projection of the torrentiality index for severe climate change scenarios, as well as climate change factors, show an increase in the frequency and magnitude of the heaviest rainfall. This fact corroborates the hypothesis of a greater general torrentiality in future rains in this specific area of the Spanish Mediterranean coast,” they conclude in their article published in Theoretical and Applied Climatology.
The results are similar to those obtained by other scientists in other regions of the planet, for example, in 2022 an investigation determined that, even in a scenario of moderate climate change, almost the entire continental territory of the India (~82–99% of spatial extent) would be affected by a significant increase (on average 19%) in hourly precipitation intensity.
For now, some of the scientists consulted by Science Middle Center They agree that the magnitude of the disaster in Valencia could be a starting point to rethink risk management: from the protocols that are applied to warn the population, to the design of the landscape.
Meanwhile, the State Meteorological Agency has announced that intense episodes of rain will continue in the north of the Valencian Communitysome of the most affected points could be Aragonthe south of Navarre and the west of Andalusia.
It has been pointed out that the death toll from the storm could be the worst in the modern history of Spain, since the number of victims exceeded that recorded during the catastrophe that occurred in the ravine of Aras in August 1996.
LHM