DANA announced by Aemet eventually brought power. And while it was disastrous in some parts of Spain, in the city of Madrid its impact ended up being far less than expected. Something that caused complaints from a part of the population that believes that The agency allowed extreme alarmization and was mistaken in its forecasts.

Added to this criticism were some government officials, such as Jorge Buxade, VOX’s first vice president for political action, Juan Manuel Moreno Bonilla, president of the Junta of Andalusia, or José Luis Martínez-Almeida, mayor of the capital, who described the government’s forecast as “a ruling “, which this can affect the “authority” of institutions over citizens. Therefore, he asked to “correct” forecasts in the future.

To questions from this newspaper, from Aemet, they refused to answer the criticism. But they are convinced that “the formation of DANA and most of its effects they modeled pretty well“Though they admit they were wrong about some things.

And they give some examples. “Precipitation in Catalonia remained in the far south and west, despite the fact that a slightly larger increase was expected. Some isolated rainfall systems have been more important than expected, such as San José in Cadiz. the exact position of the plumes of precipitation and their change over several hours remains an unresolved issue. In any case, this is the subject of detailed technical study,” the government agency explained.

However, the criticism of Aemet’s work stems from a deep ignorance of the weather forecasting system, which is based on scientific calculations, but which, despite being greatly improved in recent years, It still has limitations. Something that, in this particular case, was also combined with a phenomenon like DANA, which is particularly difficult to predict.

Limitations of weather forecasting

A few weeks ago, Rubén del Campo, a spokesperson for Aemet, explained in He Independent keys to weather forecasting models. And the first thing that caught my eye was that They are usually held in large areas.. Because trying to determine the exact time when it will be in a city or even in a specific area is almost impossible.

Secondly, it is important to understand that weather forecasting based on probability (scientific method, but not exact). And the probability is in percent. And this means that when we see a sun, cloud or rain icon in our city, this does not mean that it will happen 100%, but rather that it is most likely to happen.

Del Campo illustrates this: “We put 50 atmospheric data into a supercomputer to get a better idea of ​​the state of the atmosphere. the computer produces 50 different weather forecasts. If out of all 25 we are told that it is raining in Madrid, then this means that there is a 50% chance that it will rain in the capital. If he tells us that it will only rain 5 times out of 50, the rain forecast will be 10%.”

Thus, if the probability of rain in the city is 60% and finally it does not rain, this does not mean that Aemet is wrong in his forecast, because the probability that it will not rain was 40%. That’s why it’s important to look at percentages.. “Unfortunately Meteorological science is not accurate and can never guarantee what the weather will be like.”, – said del Campo in detail.

DANA Prediction Difficulties

But, as explained above, in this case, these limitations are combined with a particularly complex phenomenon. “Criticism of Aemet by some political leaders demonstrate ignorance of how DANAs work. And one of the main challenges facing us as weather communicators is to explain why it is so difficult to predict their consequences,” says Samuel Biner, an expert at Meteored.

As Biner explains, DANAs are associated with convective trains or thunderstorms. very irregular character and quite local. This means that in certain places they can drop large showers of water, while in other very close places the rains are “virtually not even suspected.”

This is because precipitation is organized into very narrow lanes that can accumulate a lot of water in certain places. This means that any slight change in the DANA trajectory results in the bulk of the precipitation moving several kilometers in either direction or starting earlier or later than expected.

Despite this, Biner assures that DANA forecasting models in recent years they have made a “big leap”. And it is this that ensures that these predictions, although they continue to have limitations, were downright “inconceivable” 10 or 15 years ago.

Expert opinion

“In my opinion, Aemet’s warnings were carried out very well, as were the civil protection warnings. If they hadn’t been released, more people would have died. In fact, thanks to Aemet’s warnings, numerous human casualties have been avoided in recent years, because earlier these episodes left more deaths, and now most of those that occur are due to negligence,” Biner says.

According to him, warnings are issued taking into account certain rainfall thresholds (in Madrid, 120 liters in 12 hours).. But they are produced not by municipalities, but by territorial divisions. And the capital of Madrid belongs to the southern half of the Community, where the most precipitation fell (in some places up to 200 liters).

“Madrid city fought for 20 kilometers. But in previous days, models have indicated that minimal changes in the position of DANA could affect other directions. If DANA completely affected Madrid, we would be talking about chaos and absolute disaster. New Philomena in the form of tornadoes. So everything was done right,” says Biner.

With all this, the Meteored expert clearly articulates his position: “We want to congratulate, congratulate and support Aemet. We believe that the forecast turned out to be very accurate. And the alert system, while it could be improved, is a great idea that puts us ahead of countries like Japan or the US. We are on the right track.”

In the same vein, Pedro Dorta, Director of the Department of Disaster Risk Reduction and tenured professor of physical geography at the University of La Laguna (Tenerife), notes: “The forecast turned out to be very good. It didn’t fail because it was made for a relatively large area. and, as you can see, serious problems arose. But, fortunately, Madrid didn’t get that much rainfall.

Dorta believes that the problems that have arisen in Madrid more related to land and resource planning than with a bad weather forecast. And as an example, he cites the floods that were observed in the subway and houses, or the problems that trains encountered. The lack of adaptation, which he believes, if not corrected, will only lead to more problems in the future, also caused by the effects of climate change.

“They throw balls. It is impossible to avoid rain, but its consequences can”, – says Dorta. – The worst thing we can do is to politicize science, and they are already doing it. One side thinks this way, the other thinks differently. But forecasting is a science based on very complex models. And science is objective. That is why the success rate of Aemet and the meteorological services is very high. Therefore, I do not think that such statements help the proper management of civil protection at all,” the expert concludes.