Posted on August 18, 2021 by Tim Eagan
I took a class last weekend about wildfires. The focus of the two-day course was a detailed examination of exactly what happens when a wildland fire burns down your house…or doesn’t. We got pretty deeply into the data about what is going on during one of these events, and the search offered a number of surprises.
I used to have a pretty dramatic notion of how wildfires destroyed homes. I imagined the fire as an irresistible, all-consuming monster that swept across a landscape consuming everything in its path. The metaphor did not come with much in the way of specifics, but it did carry a full load of emotional baggage, especially fear.
I did pick up some hard-won specifics last year when the path that the monster took came close enough to my house to destroy the homes of two neighbors only yards away. The monster never showed itself in the way my metaphor suggested. There was no three hundred foot wall of flame, no exploding buildings, no howling behemoth of incineration. Instead, it operated remotely with windblown embers that could travel for miles. If one of those embers (“firebrands”, the pros call them) were to find a small collection of dry leaves, twigs, or other natural detritus and ignite it, then that is where the trouble started. If the collection was sufficiently large (not very large at all, as it turned out), it might burn long enough to spread to other fuel and finally to a dwelling.
The speed and intensity with which such accumulations burn does not need to be high. As long as there is more fuel nearby to sustain the flame, it might go anywhere, slowly but dangerously.
In fact, I learned over the weekend that even when the monster is right there within a relatively short distance of your home, fully visible and giving off immense amounts of radiant heat, it is not the huge flames themselves that consume the structure. Rather, it is small, ignitable accumulations very close to the building (or some fuel source attached to it) that are the immediate source of danger.
Even if the building is heated well beyond human tolerances, even if it is charred by the heat, it will not ignite if there is no flame right next to the building to set it off. If this small flame is not there to ignite the flammable gas being released by the charring, the monster will often roar past and leave the home intact. As in the case of a creeping fire set off by a firebrand, some small pile of burning fuel very near the building is what would be needed to activate ignition.
This new notion about the nature of wildfire has been an inspiration to me. There is something about being able to protect your home from a rampaging, all-powerful monster just by doing a little light raking that is very appealing. I sense that there is some very zen lesson to be drawn from that irony, but I still haven’t been able to put my finger on it. If I find it, perhaps it will be useful in dealing with some other monsters…like the virus, the climate, injustice, or death itself.
There is, of course, a whole list of other fire safety measures that deserves attention. But what fun is there in thinking about putting on a new roof? For now I am happy to meditate on the idea of one man against the monster, armed only with a rake.
I used to have a pretty dramatic notion of how wildfires destroyed homes. I imagined the fire as an irresistible, all-consuming monster that swept across a landscape consuming everything in its path. The metaphor did not come with much in the way of specifics, but it did carry a full load of emotional baggage, especially fear.
I did pick up some hard-won specifics last year when the path that the monster took came close enough to my house to destroy the homes of two neighbors only yards away. The monster never showed itself in the way my metaphor suggested. There was no three hundred foot wall of flame, no exploding buildings, no howling behemoth of incineration. Instead, it operated remotely with windblown embers that could travel for miles. If one of those embers (“firebrands”, the pros call them) were to find a small collection of dry leaves, twigs, or other natural detritus and ignite it, then that is where the trouble started. If the collection was sufficiently large (not very large at all, as it turned out), it might burn long enough to spread to other fuel and finally to a dwelling.
The speed and intensity with which such accumulations burn does not need to be high. As long as there is more fuel nearby to sustain the flame, it might go anywhere, slowly but dangerously.
In fact, I learned over the weekend that even when the monster is right there within a relatively short distance of your home, fully visible and giving off immense amounts of radiant heat, it is not the huge flames themselves that consume the structure. Rather, it is small, ignitable accumulations very close to the building (or some fuel source attached to it) that are the immediate source of danger.
Even if the building is heated well beyond human tolerances, even if it is charred by the heat, it will not ignite if there is no flame right next to the building to set it off. If this small flame is not there to ignite the flammable gas being released by the charring, the monster will often roar past and leave the home intact. As in the case of a creeping fire set off by a firebrand, some small pile of burning fuel very near the building is what would be needed to activate ignition.
This new notion about the nature of wildfire has been an inspiration to me. There is something about being able to protect your home from a rampaging, all-powerful monster just by doing a little light raking that is very appealing. I sense that there is some very zen lesson to be drawn from that irony, but I still haven’t been able to put my finger on it. If I find it, perhaps it will be useful in dealing with some other monsters…like the virus, the climate, injustice, or death itself.
There is, of course, a whole list of other fire safety measures that deserves attention. But what fun is there in thinking about putting on a new roof? For now I am happy to meditate on the idea of one man against the monster, armed only with a rake.