“There are several key ingredients needed for wildfires. They need favorable weather, namely dry and windy conditions. They need fuel. And they need an ignition source.
The California Department of Forestry and Fire Protection said that they are still investigating the origins of most of the blazes underway. But other factors this year stacked the deck in favor of massive conflagrations.
California and much of the western US are in the midst of a years-long drought. With limited moisture, plants dry out and turn into kindling. Ordinarily, vegetation at higher altitudes would still hang onto some moisture and act as a barrier to wildfires in places like the Sierra Nevada. However, the severity of the drought has caused even this greenery to turn yellow and gray.”
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“human activity has made wildfires worse at every step. Climate change caused by burning fossil fuels is increasing the aridity of western forests and increasing the frequency and severity of extreme heat events.
People are also building closer to wildland areas. That means that when fires do occur, they cause more damage to homes and businesses. That proximity also means that humans are more likely to spark new infernos. The vast majority of wildfires are ignited by people, up to 84 percent, whether through errant sparks, downed power lines, or arson.
And for hundreds of years, people have suppressed naturally occurring fires. European settlers also halted cultural burning practices from the Indigenous people of the region. Stopping these smaller fires has allowed forests, grasslands, and chaparral to grow much denser than they would otherwise. Paradoxically, that means more fuel is available to burn when fires do occur, causing blazes to spread farther and faster.”
https://www.vox.com/22652678/dixie-caldor-wildfire-california-sierra-nevada-drought-climate