There has been a big PR effort by the fossil fuels industry to blame arson, when that's been responsible for a fraction of fires forever. What's changed is the higher temperatures and lower humidity that goes with them, letting otherwise easily-contained fires grow rapidly. And that change is a result of burning fossil fuels.

Fire investigators can often tell where a fire started and can detect chemicals that are sometimes used to start fires.

There was a large fire near me where people were seen throwing fireworks down a hill.

Well we know it was arson by fossil fuel companies.