A winter heat wave reigned Thursday, February 10 over part of California, risking to worsen an already chronic drought and raising fears of a particularly early fire season this year.
Read alsoCalifornia struggling with a historic drought
Fanned by hot winds and very low humidity, a predawn fire broke out in the hills above the upscale beach town of Laguna Beach, south of Los Angeles, where evacuation orders were issued. given in some areas.
The fire, fought by more than 200 firefighters helped by water bombers, had already covered nearly 60 hectares by midday but was not progressing towards homes.
In Southern California, the meteorological services had issued an alert concerning these unusual heat, with temperatures which could exceed 32° C in various points of the region.
These out-of-season temperatures, on average 10°C higher than seasonal norms, are expected to last until Sunday, the day of the American football championship final held in Los Angeles.
Several heat records
The heat record for a Super Bowl final, set in 1973 at nearly 29°C – already in Los Angeles – could be beaten, experts believe.
“
Right now you have this high pressure system and drier conditions on the surface (…) And also we live on a planet whose climate we have warmed up, so just from a purely statistical point of view , we are going to see a record increase
,” notes Justin Mankin, climate scientist at the American University of Dartmouth.
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This unseasonable heat also extends further north, in the San Francisco area for example where several heat records were broken for February 9, with 28.3°C recorded in Salinas against 27.2°C four years earlier.
The hope of halting a cycle of chronic drought that had been sparked by spectacular snowfalls on the Californian peaks at the end of December did not last.
A laboratory at the University of Berkeley, specializing in the study of snow on the central Sierra Nevada, raised a sad record on Wednesday: "
the longest winter period without any precipitation
", with 32 consecutive dry days.
The previous record was set in 1990. “
What prevents fires is rain and precipitation.
And this kind of heat phenomenon tends to suggest that there is a risk of having a very early start to the wildfire season in California
, ”said Justin Mankin.
"
It's almost to the point where it feels like this season never ends
," he added.
More than 10,000 km² of vegetation burned last year in California, the second worst year in history.
The number and intensity of fires have multiplied in recent years throughout the western United States, with a very marked lengthening of the fire season, a phenomenon linked in particular to global warming.