“The electricity has been cut off, my mother and her neighbors are here. They say it will rain until 5:00 a.m., which worries us a little. For the moment, it doesn’t stop.” This is the story of Khadya, 26, who lives in El Aaiún, one of the Sahrawi refugee camps in southern Algeria. In the early hours of Saturday to Sunday, she and her family were preparing with flashlights and charged mobile phones for a totally unusual scenario predicted by meteorologists a few days before: heavy rains in the Sahara desert, well above the annual average.
A few hours later, the roads that connect the Sahrawi camps to Tindouf were cut by mud and partially flooded, as shown in videos sent by Khaled Mohammed, president of Juventud Activa Saharawi. “We have had a day of very intense rain in the Sahrawi refugee camps,” he tells elDiario.es. “We are still nervous, because the houses are made of adobe, they can get wet and could collapse in the coming days.”
The forecast made by the European Centre for Medium-Range Weather Forecasts (ECMWF), and advanced by elDiario.es, has been realized in several desert regions of North Africa, where for several days rains reaching up to 50 liters per square meter have been recorded. . in some areas.
In Morocco and Algeria, torrential rains left nearly twenty dead and nine missing, in addition to destroying homes and infrastructure related to drinking water and electricity. In the Sahrawi camps, bread could not arrive for several hours because communications were blocked.
How much has it rained in the Sahara?
Collecting rainfall data in these regions is complicated for a very simple reason: there are no weather stations or rain gauges in a place like the Sahara Desert. However, images collected by different satellites give us an idea of the extent to which ECMWF’s predictions have come true. Data from NOAA (the US National Oceanic and Atmospheric Administration) show that the most intense outbreaks are precisely in the area of the Sahrawi camps and in the very interior areas of the desert.
Even more telling is the accumulated precipitation record from NOAA satellite data during the first few days of September, showing a heavy accumulation of rain in one of the driest regions on the planet.
“Calculating accumulated precipitation is not trivial; it takes time and there are many nuances,” he explains. Francisco J. TapiadorProfessor of Earth Physics at the University of Castilla-La Mancha (UCLM). Using data from NASA’s GPM-CORE satellite, merged with infrared data from geostationary satellites, the expert calculates that on days like September 7, from 06:00 to 06:30, they fell in the order of 20 liters per hour in some areas. a large amount of precipitation for that region. These images are better than those based only on infrared data, which give us the height of the cloud but have an indirect relationship with precipitation on the ground, but to know more precisely how much precipitation fell in total, more analysis.
“The predictions came true”
“I feel like the forecasts have largely come true,” the meteorologist said. Angel Riveraexpert in atmospheric dynamics. “The Moroccan meteorological service has issued a red notice,” he emphasizes. For Francisco Martin Leonmeteorologist and coordinator of RAM (Meteorology Amateur Magazine), it rained a lot. “In places where it normally rains little or extremely little, a maximum of 16 liters fell, which is extraordinary for a desert,” he says. “In northern Algeria and Morocco, the southern tropical wave interacted with the cold trough – the dana – that we had on the peninsula. And in Mauritania, there were also rainy areas according to satellite images,” he says.
“But the flood must be largely nuanced, and of course the torrential rains that the models gave 10 days earlier were overestimated,” warns Martín León. In the end, he explains, the forecasts softened the precipitation, even if they maintained the intense rains of the Atlas of northern Morocco, Algeria and an area of Mauritania.
The suspect: climate change
Can this unusual phenomenon be attributed to climate change? To know for sure we will have to wait for attribution studies, but the anomaly is part of a context of major atmospheric alterations, such as this displacement of the Intertropical Convergence Zone (ITCZ), a band of clouds, rain, storms and precipitation that extends across the equator, further north than usual. This anomaly occurs in a context where the tropical rains move further northconsequence of the climate crisis.
“We must bear in mind that we are in a situation in which we have never been in modern times, with very warm seas, with a wild Atlantic, with a Mediterranean with extremely high temperatures, with an atmosphere doped with more heat and more water vapor, and all this proves that climate change could be the cause,” says Martín León. “There is increasing evidence of changes in weather conditions and atmospheric dynamics that may be related to the accelerated warming that is occurring on the planet,” he emphasizes. Jose Miguel VinasMeteoric meteorologist.
