Between drought and extreme rains, California on the front line of global warming

Between drought and extreme rains, California on the front line of global warming

LOS ANGELES, United States | Last Saturday, the capital of California broke its record for days without rain, the next day, Sacramento recorded a historic record for precipitation: these extreme variations are increasingly frequent in the American West and foreshadow what climate change has in store for the rest. from the country.

• Read also: When science makes the link between climate change and disasters

• Read also: When the rise in temperatures becomes unsustainable

“See when you take a canary to a coal mine and you know the air is poisonous because the canary dies? California is like the canary,” says Justin Mankin, professor at the American University of Dartmouth.

For this researcher, California, the most populous American state and alone equivalent to the fifth largest economy in the world, is a "crucial indicator of a society's ability to respond to this type of climatic stress".

Dramatic variations have always been part of the Californian climate, but global warming has accentuated the phenomenon. “We see very intense dry seasons which are accompanied by the risk of fires, droughts and heat waves, punctuated by these very, very heavy showers with mudslides, landslides and floods”, details Mr Mankin.

Just look at the data for the last quarter to understand the impact of this ups and downs in the weather: first emergency calls from the authorities to save water, then a wave of deaths linked to extreme heat ahead of gigantic fires that have covered more than 10,000 km2 this year in California.

Some upstate residents have gone, in a thunderous roll, from evacuations related to wildfires to roads cut off by intense rains this past weekend.

"Not suitable"

Between drought and extreme rains, California on the front line of global warming

These variations have steadily increased in intensity over the past decade and that should come as no surprise, says Marty Ralph, director of a center for the study of extreme weather events in the American West. This is “consistent with what climate projections indicated,” says the San Diego-based researcher.

Will California be able to get through such phenomena unscathed? "I honestly don't know. What I can say from the weather events of the last few months is that Californians are not well adapted to the type of weather they have right now, let alone what to expect,” Mankin replies.

“It will be more difficult for current infrastructure to collect enough water during shorter rainy periods,” says Marty Ralph.

The key for him lies in the ability to better anticipate intense rain events and in the adaptation of canals and dams. “If we have a reliable forecasting system, we can release water before the storms to help absorb the floods,” he explains.

The torrential rains have certainly put a stop to the fire season, but are not enough to solve the chronic drought that is raging in the West.

“The drought will still be there next week. It's like if you owe 1000 dollars and you earn 200, you still owe 800 dollars, "says Justin Mankin.

For California, climate change is not a possibility, it is already a reality, he recalls, as world leaders prepare to gather on Sunday in Glasgow (Scotland) for COP26 , a crucial conference in the fight against global warming.

“If we limit our (greenhouse gas) emissions — which should be our immediate priority — we will just keep it from getting worse. This will not prevent it from happening, ”warns the researcher.

“What the best available scientific predictions show is that the climate is changing. He has changed and he will probably continue to do so,” adds Marty Ralph.

“It’s a very slow movement compared to the life of a human being. On a planetary scale, it’s a snap,” he says.

SEE ALSO...