In January it is cold and it is the coldest month of the year in Spain.
This classic statement that all primary school children study needs to be clearly revised in view of the compelling data from the latest analysis by meteorologist Roberto Granda, published this Wednesday in eltiempo.es, which points to the fact that it is getting less and less cold in the middle of winter in Spain. .
Granda has compared the number of warm days that occurred this month in the sixties of the last century with today and his conclusion is that they have doubled and now represent 25%.
But the “most striking, paradigmatic and surprising” example is the Barcelona-Fabra observatory, where warm days quadruple from two to 11. Of all the stations analyzed, this brutal increase only occurs there.
Added to this increase in daytime heat is that of daytime heat, which means that frosts have also decreased by 30% since the sixties throughout the season and the country, according to another recent study by the same author.
Since Tuesday, the country has been immersed in a new episode of anomalous heat, which will trigger thermometers of 27° and 28° in the southeast at the end of January.
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For Granda, interviewed by telephone by this newspaper, it is one of the “most forceful analyzes” that he has carried out so far, since it is not one or two, but “double” and, in the face of such emphaticity, “there is no room to appeal.” to the natural variability of the climate” except in the case of Izaña (Tenerife), the station in which a decrease of -1.2 days occurs.
Nor can it be explained by the heat island effect - the increase in temperature suffered by large cities due to human activity - since "the same trend, a clear and evident rise" occurs in large municipalities as well as in resorts. that are in towns or outside urban limits and at a higher altitude.
To begin with, the meteorologist has asked himself what can be considered a warm day and, as there is no "exact definition", he has placed the threshold at the 80th percentile, that is, a warm day would be one in which the maximum temperatures Officials, those registered in the OpenData system of the State Meteorological Agency (Aemet), are among the 20% of the warmest of the reference period, the most recent, which goes from 1991 to 2020.
Granda has determined the days on which this threshold is equaled or exceeded season by season, first year by year and then by decade, in the historical series, which goes between 1960 and 2022. The expert has ruled out recent observatories, which They have gaps in the figures and those that have changed locations.
"There are more than 50 stations spread throughout the country, including the main cities such as Madrid, Barcelona, Valencia and Seville."
The difference between what happened in the sixties and today is abysmal.
“In Spain as a whole, the number of warm days has doubled, generally going from four a month to eight, an increase of a little more than 25%,” says Granda, for whom the serious thing is that “there are seasons in which it is not that it has doubled, like Almería, it is that it has tripled - from three to nine -, even multiplied by four, as is the case of Barcelona-Fabra, which is the most striking of all, the one that stands out the most.”
In this station, which is in the Collserola mountain range, near Tibidabo, the number of very warm days - 90th percentile - has also quadrupled, from one a year to four or five.
The increase is “more pronounced in the south, the interior and the east.”
And especially “it is very noticeable, especially in high areas, more than in low areas.”
For example in Soria ―from four warm days to 10―, Cuenca ―from four to nine―, Navacerrada (Madrid) ―from three to eight―, Daroca (Zaragoza) ―from five to nine―...
And the worst thing is that it is a trend that is getting worse.
Since the 1960s, the rise was “more or less gradual and gentle” but, starting in the 2000s, “it is much more accelerated, and in the last four or five years, even more pronounced.”
Granda is not at all surprised, since Spain experienced its fifth consecutive warm winter for the first time last year.
If you look back, you have to go back to the 2017-2018 season to find a cold winter.
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The cause is “the same as always”: “The evident change in atmospheric conditions due to the hand of man in recent decades, which has translated into changes in patterns and changes in surface, from rainfall to temperatures. .
There is probably a direct correlation, a study is needed, but everything seems to indicate it.”
These changes in patterns are producing an increase in stable situations, with very powerful ridges as is happening these days, which translate into higher temperatures, necessarily, on the surface, especially in maximum temperatures."
The consequences are fatal and occur at all levels.
To begin with, the days when it is hotter are obviously because there is more sun, that is, it rains less.
To continue, the cold is a “natural limitation”.
"There are many animal species, especially those that are pests such as rats, mosquitoes and processionary, whose development is favored by greater daytime heat."
High daytime temperatures also cause “sap circulation to start earlier than it should” in many trees.
For example, "the pruning of the vineyards in La Mancha was previously carried out in March, even in April, and with these maximums by then the vines are already active."
Another case is that of the almond tree, which in Madrid bloomed in March and now does so at the beginning of February, with the danger that late frosts will destroy its flowers.
“It is an indication that something is not right,” he says.
Apart from crops, it affects all vegetation and fauna.
“Altered seasons, which have inappropriate temperatures, affect the life cycles of all living beings,” summarizes Granda.
And finally, “the higher the temperature, the greater evapotranspiration, that is, more water loss, both from reservoirs and from the soil” in a context in which, in addition, it rains less.
“The fact that it is so hot for the season affects everything,” concludes the expert, who does not understand how there are so many people who doubt climate change, who “don't want to see it.”
“Rose-colored glasses look great, but reality is what it is,” he says.