It's a complex issue. Comparisons to the early 20th century have issues - for example, California's human population was about five million then, and it's fort

It's a complex issue. Comparisons to the early 20th century have issues - for example, California's human population was about five million then, and it's forty million now, and was twenty million in 1970. There's been deforestation, movement of people into the woods, some replacement of pines by oaks, etc. Regardless, the five-fold increase in wildfires since 1970 in California are closely correlated with the amount of moisture in soil and vegetation in the summer, and fossil-fueled global warming is the culprit for that shift: > "Most of the increase in burned area seen since 1972 has been because of an increase in summer forest fires, mostly in Northern California and the Sierras. That increase, in turn, can be almost entirely explained by a rise in aridity, which is caused by warming, and consistent with climate change models. Just a small amount of warming causes exponential increases in aridity, drying out fuels, so summer forest fires could get a lot worse with further warming if fuels remain abundant." https://www.nps.gov/articles/how-is-climate-change-already-impacting-california-wildfires.htm https://www.nps.gov/articles/how-is-climate-change-already-i...