Dec 19: Wildfires run faster

[Garett Dworman]

Remember the wildfire scene in Bambi? Where Bambi and all the other animals are running for their lives from the wildfire? The fire that was started by an unattended campfire? The scary thing is, this scene is both realistic — animals try to outrun a wildfire — and unrealistic — it’s unlikely that so many of them make it.

You see, wildfires can run faster.

How fast, exactly, depends on three factors:

• Fuel: What’s burning, how dry it is, how much there is, and how dense it is

• Weather: How windy it is, how hot the air is, and how humid it is

• Topography: How hilly the terrain is, how steep it is, and how contours run

The numbers commonly cited as the typical maximum “forward rate of spread” (FROS) are

• 6.7 mph (10.8 kph) in forests

• 14 mph (22 kph) in grasslands

As in the movie, Bambi may be able to make it out. White-tailed deer can run up to 30 mph (48.2 kph). Presumably, that is on level grasslands, not in a forest.

But humans are unlikely to fare as well. The average completion time for a 10K footrace is 1 hour. So, if you are on the fast side of the average, you might outrun the fire. IF the fire is burning through a forest, AND you’re running on a typical 10K route, that is, reasonably flat, with good footing and no obstructions.

Your best bet is not to be there in the first place. Humans cause 90% of wildfires. Do your part to keep from starting one. If you are in a fire zone, get out as quickly as you can.

But, if you are a backcountry camper, here are some tips for surviving should you find yourself in a bad situation.