Why do the flames on the forest fires go so high?

What exactly is burning up there? Isn’t the fuel source about fifty feet lower?

Flame is burning gases, not burning wood. The heat from fires convert materials in wood into gases, the gases catch fire. The hotter the gases and the greater the volume, the higher the flames rise. Look at a candle, neither the wick or the wax is actually on fire. The heat from the flame liquifies the wax, it is drawn up the wick, it is heated further into a gas, and that gas then catches fire.

Flammable gases. Whenever you see fire you are seeing the burning of gas, not of the paper or wood or wax, or whatever appears to be the nominal fuel. The heat of the combustion releases the gases, and the gases are what burn.

So the burning of all those trees releases lots of gas that rises far above the trees and burns with a bright yellow flame.

(I’m dredging this up from a high school physics class from sometime in the last century, so I stand ready to be corrected.)

Damn, ftg beat me to it!

Some fires get so large as to create their own weather. At that point, all bets are off. If the fire danger is already extreme, the firestorm is basically unstoppable by fire fighters.

I’ve seen flame heights measured in excess of 400 to 500 feet. The firestorms are immense. You can be miles away and still suffered skin burns. On one fire this past summer I was asked to create a photographic record of a developing firestorm. I took pictures every five minutes for more than three hours, all from a single location. The fire behavior specialist told us the firestorm was in excess of 40,000 feet before upper level winds began shearing off the smoke tops. Even so, at that height we could see ice crystals forming near the smoke clouds.

Last night, while vigorously browsing various news sites that had information about the California fires (my wife’s aunt’s house is in Crestline and is in severe danger of burning down, so we have a vested interest in keeping informed on the subject), I happened upon a satellite photo of southern California. It was astounding how far out over the Pacific the smoke trails went. They basically looked like white cones, starting from some inland location and rocketing out over the ocean, spreading out gloriously, for … a hundred miles? Two? I don’t know, there was no scale so my guess could be wildly inaccurate.

But it was astounding to think that somebody on a raft way out in the Pacific could have their entire sky blotted out by microscopic remnants of trees that were sitting peacefully with their friends just a few dozen hours earlier.

I have a house in Crestline where my son lives. From Crestline to the beach at Santa Monica is about 75 miles.

OK, so if the origin of the cones of smoke was roughly 75 miles from the water’s edge (or even 50 miles, if you were talking about driving distance and not straight-line distance) then the smoke extended at least 200 miles out over the ocean, and probably more. Wow.