It tingles at the extremities. The weather, until then mild and humid, gave way on Monday January 8 to authentic winter. A cold episode, forecast to last several days according to Météo-France, hit the whole of France.
The thermometer thus displayed -1°C Monday afternoon in Rouen, Lille, Paris and Metz, -2°C in Belfort, 0°C in Strasbourg or Tours… During the week, Météo-France forecasts frosts on “almost the whole country”with the exception of the tip of Cotentin and the Côte d’Azur.
These temperatures are certainly below seasonal norms, but they are far from unusual. And they do not contradict the worrying trajectory of global warming, caused by greenhouse gas emissions from human activities.
An unprecedented cold episode for almost six years…
Monday, the first day of this cold episode, the temperature was below seasonal norms across the whole of France, with the exception of the Côte d’Azur and Corsica, both slightly above normals. In Lille, it was 7.1°C colder than the average temperature recorded for January 8 between 1971 and 2020. In Paris, we observed 6.5°C less than this average, 5.9° C less in Nantes or even 4°C less in Nancy.
Tuesday, the day announced as the coldest of this episode, the national thermal indicator (the daily average of the average air temperature recorded in 30 meteorological stations representative of the territory) could fall below 0°C. A first since February 2018, underlines Météo-France.
However, this was once an ordinary situation in winter, as evidenced by this graph shared on Saturday by meteorologist Guillaume Séchet. We can see the number of days in which this situation occurred each year.
🔵#Cold : the national thermal indicator could be negative on Tuesday, a first in 6 years (02/28/18).
However, such a situation is commonplace compared to previous decades. We will not speak of a “cold wave” by the way.
👉Our news > https://t.co/9c5Uu8Oaux pic.twitter.com/Uz705iL7gQ
— Guillaume Séchet (@Meteovilles) January 6, 2024
…but fewer and fewer cold days
If episodes of extreme heat are more and more frequent in summer, due to global warming, episodes of extreme cold are increasingly rare as the winters progress. Requesting our memory, a tweet from the Infoclimat association recalled on Saturday that the level of temperatures expected this week had been reached “one year out of two before the year 2000”.
On the following graph, which shows the temperature differences with the daily averages for a year, we see that the days warmer than normal were far more numerous than those colder than average. But there are still days when the temperature is colder than the seasonal norm.
“Yes, it’s normal to have low temperatures, colder than normal,” Patrick Galois, forecaster at Météo-France, confirmed to franceinfo on Thursday. “The normals, which are currently those between 1971 and 2020, are averages. It is therefore sometimes lower (…). We are going through a much milder winter than normal, and one week of cold will not be enough to tip the scales swing the other way.”
A warming trend that persists
To the climate skeptics who would take advantage of these chilly days to pretend that global warming does not exist, “it must be said: a cold episode like the one we are experiencing this week in no way invalidates climate change”, warned climate political scientist François Gemenne on Monday on franceinfo. Climatologist Jean Jouzel, former vice-president of the Intergovernmental Panel on Climate Change (IPCC) and pioneer in the study of global warming, made a logical decision on TF1 on Sunday “we are in winter” to describe the days to come.
These occasional temperature variations do not change the trend observed in the long term. THE Average temperatures are rising on a global scale, but also in France, where the year 2023 was the second hottest year ever recorded after 2022, according to Météo-France.
The forecaster also specifies that the current episode does not correspond at this stage to the criteria for a “cold wave” (the thermal indicator must therefore pass at least one day below -2°C and not spend more than two days above 0.9°C). “With climate change, cold spells are still possible, even as the climate warms globally,” further specifies Météo-France, which notes however that “the four longest and most severe cold spells (February 1956, January 1963, January 1985 and January 1987) were observed more than 30 years ago.”
During this last exceptional wave, Marseille saw the mercury drop to -10°C, Clermont-Ferrand to -15.4°C, and Bordeaux to -11.1°C. At the very beginning of 2024, Jean Jouzel notes that “vsWhat is perhaps a little exceptional is this contrast between a month of December who was extremely gentle and this beginning of January which will be, let’s say, wintery.”
Since the 19th century, the Earth’s average temperature has warmed by 1.1°C. Scientists have established with certainty that this increase is due to human activities, which consume fossil fuels (coal, oil and gas). This warming, unprecedented in its speed, threatens the future of our societies and biodiversity. But solutions – renewable energies, sobriety, reduced meat consumption – exist. Discover our answers to your questions about the climate crisis.