After wildfires raged in Portugal and now, more recently, Northern California, it's high time that we learn more about the origins and effects of wildfire outbreaks.
Wildfire from the Santa Rosa and Napa Valley area [Photo by Tayfun Coskun, Anadolu Agency, Getty Images]
Wildfires may be terrifyingly beautiful to look at, but they can also be quite dangerous. They can burn hundreds of thousands of hectares of land, destroy hundreds of homes, force tens of thousands to evacuate, and cause a myriad of health issues, even death. At the time of writing, the most recent wildfires that swept across California's wine country have already caused the deaths of 40 people, with dozens of others still deemed missing. What's more, the smoke from the fires can even contribute to global pollution.
Worse still, a 2016 NASA study found that the heat from the fires can contribute to global temperature increase.
So how do wildfires start? Are certain places more prone to them that most others? Will the place you live in ever be in danger of wildfires? Let's find out.
The burned-out hulks of vehicles and a wheelchair in the aftermath of the California wildfires. [Photo by Genaro Molina/Los Angeles Times]
First things first: what causes wildfires? A lot of the time, it’s people. In fact, in California, 95% of wildfires are started by human activities. So what about the wildfires that aren't started by people?
There are three things that, as a combination, will make it likely that a wildfire will start. These three things are oxygen, fuel, and a source of heat. So if an area is experiencing strong winds, drought, and dry weather, it's likely that things will burn. A single small spark can turn into a devastating blaze that can last for weeks and consume hectares upon hectares of hand.
Global warming can also indirectly cause wildfires. Every degree of temperature increase in global temperature increases lightning activity by 12%. Lightning, as you may have predicted or already known, is another possible cause of wildfires.
Surprisingly, wildfires used to be beneficial in certain landscapes, like the forest. A small wildfire can rid the forest of underbrush, thus giving other species of plant to thrive. However, in California at least, there has been a decades-long fear of any kind of wildfire. The problem is that suppressing these low-intensity natural occurrences has actually made it possible for high-intensity wildfires to form.
A helicopter pours water over a fire that's getting close to the Ledson Winery and Historic Castle Vineyards. [Photo by Genaro Molina/Los Angeles Times]
If fires can be beneficial, can people have a better relationship with them? Apparently, yes. Fire crews can put out fires in fire-prone areas, but they need to learn to naturally let fires burn themselves out in other areas instead of putting them out.
In any case, however, an uncontained and destructive wildfire can wreak havoc on the environment, on wildlife, and on humans. The fires can worsen global warming, and they can impact our health as well as cost us our livelihoods, homes, and even our lives. Meanwhile, though some animals have evolved to be able to adapt to large fires, some aren’t so lucky.
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