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A pregnant woman had a job en route while she was evacuated. Videos have shown dozens of poignant impulses through fiery landscapes. Advocacy appeared on social media to locate their loved ones. Survivors of a mbad shootings were forced to flee in front of the flames
It's California since the camp fire broke out early Thursday morning, burning 80 hectares by the minute and devastating the city of Paradise, in the north of the country. Later in the day, the Woolsey fire broke out in the south of Ventura and Los Angeles counties, resulting in the evacuation of Malibu as a whole.
What makes forest fires as catastrophic in California?
The Climate (Changing)
The First is the California Climate
"In some ways, fire is a very simple thing," said Park Williams, a bioclimatologist at Columbia University in Lamont. -Observatory of the Earth Doherty. "As long as the fabric is dry enough and there is a spark, it will burn."
California, like most western countries, gets most of its moisture in the fall and winter. Its vegetation then pbades much of the summer to dry out slowly due to lack of rainfall and warmer temperatures. This vegetation then serves to stoke the fires.
But while the California climate has always been subject to fire, the link between climate change and larger fires is inextricable. "Behind the scenes of all this, you have temperatures that are about two to three degrees Fahrenheit warmer than they would have been without global warming," said Dr. Williams. This dries up the vegetation even more, which makes it more likely to burn.
California's fire record dates back to 1932; Of the 10 largest fires that have occurred since then, nine have occurred since 2000, five since 2010 and two this year alone, including that of Mendocino Complex Fire, the largest in the history of the United States. # 39; State.
The perfect fire recipe is kind of written in California, "said Dr. Williams. "Nature creates the ideal conditions for fire, as long as people are there to light the fire. But then, climate change seems, in different ways, also weigh heavily in the dice. "
People
Even though the conditions are optimal for a forest fire, you still need something or something to turn on." Sometimes the trigger is kind, like a love at first sight, but most often humans are responsible.
"Many of the big fires you see in southern California that affect inhabited areas are caused by humans," Said Nina S. Oakley, Assistant Professor of Research on Atmospheric Sciences at the Desert Research Institute.
Deadly fires in and around Sonoma County were provoked last year by This year's fire, the sixth largest ever, began when a truck emptied its tire and its rim scratched the sidewalk, throwing sparks.
California has a lot of people and a very long dry season "Dr. Williams said. "People always create possible sparks, and as the dry season progresses and things dry up more and more, the risk of a spark occurring in a person at the wrong time simply increases. And that puts aside the arson.
People also contributed to forest fires in another way: by choosing their place of residence. People are moving more and more into areas near forests, called city-natural space interfaces, which tend to burn.
"In Nevada we have a lot of large fires, but they usually burn open spaces," Oakley says. "They do not burn in neighborhoods."
Suppression of fires
It's counterintuitive, but the United States has always strengthened forest fires.
"Since the beginning of the century we fought the fires. and we have been very successful throughout the western United States, "said Dr. Williams. "And every time we fight a fire successfully, it means that a lot of things that would have burned did not burn it. So in the last hundred years we have had a buildup of plants in many areas.
"In California, when fires break out, these fires spread to places where there are many more plants. burn that they would not have done it if they had let fires burn over the last hundred years.
In recent years, the US Forest Service has attempted to rectify past practice by using prescribed or "controlled" burns.
Santa Ana Winds
Every autumn, strong gusts called Santa Ana winds bring dry air from the Great Basin region to the west in Southern California, said Fengpeng Sun, badistant professor at Department of Geoscience of the University of Missouri-Kansas City.
Dr. Sun is co-author of a 2015 study that suggests California has two distinct fire seasons. One, which extends from June to September and is driven by a combination of warmer and drier weather, is the season of fires in the West that most people think of. These fires tend to occur more inland, in the altitude forests.
But Dr. Sun and his co-authors also identified a second fire season that spans from October to April and is driven by the winds of Santa Ana. These fires tend to spread three times faster and spread closer to urban areas. They were responsible for 80% of economic losses over two decades starting in 1990.
It's not just Santa Ana that's drying up vegetation; they also move embers and spread fires.
If the autumn rains, which generally begin in October, do not arrive at the time, as they did this year, the winds may dry up the conditions even more. already dry. According to Derek Arndt, chief of the monitoring service of the National Environmental Information Centers, part of the National Oceanic and Atmospheric Administration, Northern California can receive more than two inches of rain in October. This year, in some places, less than half of that amount has fallen.
"None of these cases is comparable to a record, historically dry for October," said Dr. Arndt. "But they are all on the dry side of the story."
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