Devastating frost in French vineyards: the number one suspect warming

The likelihood of a late frost episode like the one that ravaged several French vineyards in early April has been significantly increased by climate change and will be even more so in the future, scientists warned Tuesday (June 15).

To read also: Frost in the vineyard: the Bordelais fears a "bitter" assessment

"Probably the greatest agronomic disaster of the beginning of the 21st century"

for the French Minister of Agriculture Julien Denormandie, these frosts caused an estimated loss of one third of French wine production. Or about two billion euros in turnover for the sector, according to the agricultural union FNSEA. Arborists and beet growers had also been affected and the government released an “exceptional solidarity fund” of one billion euros for all affected farmers.

Scientists from the international network World Weather Attribution, which has made a specialty of analyzing the possible link between a specific extreme weather event and warming, worked on this episode, which had followed a period of great mildness that favored budding. cultures.

They analyzed data from an area covering in particular the vineyards of Burgundy, Champagne and the Loire Valley, also scrutinized more than a hundred climate models.

Climate change has "increased by about 60%" the likelihood of such an event occurring during a budding period.

Robert Vautard, Director of the Pierre and Simon Laplace Institute for Research in Environmental Sciences, co-author of the study

Result: climate change has

the probability of such an event occurring during a budding period, explains Robert Vautard, director of the Pierre and Simon Laplace Institute for Research in Environmental Sciences, a authors of the study. And the phenomenon is likely to

, since a warming of 2 ° C compared to the pre-industrial era, that is to say the maximum warming objective of the Paris agreement which seems for the moment outside. range, would see

the scientist.

Paradoxically, warming makes freezing episodes less frequent and less intense.

But it increases in still greater proportions the phenomena of precocious heat, as France had known in the month of March.

A sweetness that favors the

break

of the vegetation, which comes out of its winter dormancy earlier and buds.

And this process

underlines Nicolas Viovy, from the Laboratory of Environmental Climate Sciences, another author of the study:

".

Read also: In Alsace, "candles" to protect orchards from frost

Summary of the phenomenon,

, while this very notion of late evolves, earlier and earlier in the season, he continues. A complex process in which

, also underlines Samuel Morin, director of the National Meteorological Research Center, a joint CNRS / Météo France unit, who did not personally participate in the study. Three other researchers from Météo-France co-signed the report, which was based in particular on the readings of the public establishment.

“It is a real scientific step forward to be able to analyze composite events”

of this type, he insists, recalling that

. A probability whose consequences can weigh heavily, as underlined by Markus Reichstein of the German Max Planck Institute, one of the authors of the study.

.