Jessica Gilman
Appearances
Short Wave
The Science Behind Wildfire Smoke
That's one of the interesting things with smoke is that it doesn't stay where it was emitted. It travels with the wind and can impact large parts of the population well downwind of the fires.
Short Wave
The Science Behind Wildfire Smoke
Smoke is an incredibly complex mixture of different gases and particles. And if we look just at the gases, there are hundreds to thousands of different gases that are formed in biomass burning.
Short Wave
The Science Behind Wildfire Smoke
But you also get really teeny tiny particles on the order of a millionth of a meter in diameter. And those really small particles can stay in the atmosphere for a lot longer.
Short Wave
The Science Behind Wildfire Smoke
Yeah, so one of the primary hazardous air pollutants is particles that are called PM2.5s that has an overall diameter of two and a half micrometers or less. And that's roughly about 50 times smaller than a single grain of salt. So really, really small particles.
Short Wave
The Science Behind Wildfire Smoke
The smaller particles, not only can they travel further distances, but they also have this unique ability to follow the sort of micro air currents and can bend around corners and edges and everything. And that means that if you're breathing in smoke, those larger particles are going to hit the back of your throat first.
Short Wave
The Science Behind Wildfire Smoke
But the smaller particles can actually make it all the way down your throat and then deep into your lungs. And that's where they start to cause all kinds of different health effects.
Short Wave
The Science Behind Wildfire Smoke
And when they die down, that's actually when they produce quite a bit of smoke. And that mixing into a more shallow boundary layer just means you get a lot more smoke very close to the ground, particularly at night.
Short Wave
The Science Behind Wildfire Smoke
especially if you're in a kind of a mountain valley where it just starts to pool and accumulate and it's not really diluted or moved out of your immediate area until the sunrise comes, that boundary layer starts to expand, the wind speeds pick up and kind of Sure.
Short Wave
The Science Behind Wildfire Smoke
It is, yeah, and that's true of most air pollution sources, but particularly so for smoke. In many of the western states, even here in Colorado, it's not necessarily all that common that you have air conditioning. It does cool down quite a bit at night, and so that is the time people would turn on fans. etc. to try to ventilate the house, get it cool at night.
Short Wave
The Science Behind Wildfire Smoke
Of course, you're home at night sleeping and breathing all through the night. And so again, that's one way that you can be exposed to smoke that you might not necessarily think of.
Short Wave
The Science Behind Wildfire Smoke
Certain smoke plumes can literally travel the world and go to really, really remote places. Wow. And of course, with fires, you know, we're impacted here in the United States right now. But of course, that flips as we go to the next season and then the southern hemisphere. So fire is just a constant emission source, you know, across the globe.
Short Wave
The Science Behind Wildfire Smoke
And as I said, as it gets emitted into the different layers of the atmosphere, it can stay in the atmosphere longer. And that just means it can get carried by the wind currents further and further downwind. And so that smoke can just travel. tens to hundreds of miles downwind from the source. Yeah, yeah.
Short Wave
The Science Behind Wildfire Smoke
The primary component is going to be related to those particles. And so particles are something that can both cool the climate as well as heat the Earth. And so that's where that size and color of the particles really comes into play. And so the white particles. Particles that you associate with clouds generally reflect radiation back to space, so that's a cooling effect, right?
Short Wave
The Science Behind Wildfire Smoke
If you're under a cloud on a super sunny day, you immediately feel better and cooler when that cloud is overhead. The other way is that those darker particles, the black soot, those are things that readily absorb radiation from the sun, which means when the sun goes down, they can also readmit radiation. that radiation back into our atmosphere.
Short Wave
The Science Behind Wildfire Smoke
And that's what contributes to that, the global warming effect, the greenhouse gas effect that is so important for climate change. So that's one way that the aerosols play into it. Right.
Short Wave
The Science Behind Wildfire Smoke
Unfortunately, yeah. So as those particles that are released from biomass burning may impact climate and climate continues to change, which could lead to more fires and so forth, you just get that feedback where it just continues down the wrong path rather than trying to correct itself or balance itself out.
Short Wave
The Science Behind Wildfire Smoke
I hope so. I mean, there's many different really visual ways of seeing climate change with our own eyes. I mean, from the rising sea levels and daytime flooding that's happening in some of the coastal cities to the amount of runoff that you see. On the Greenland ice sheet to these huge, you know, ice shelves cleaving off of Antarctica. I mean, the signs are all around.
Short Wave
The Science Behind Wildfire Smoke
The biomass burning is certainly one that impacts, you know, a large community of people out west. And as you mentioned, it's a very... visceral response and then with climate change, you know, you often hear of global warming and of course fires represent that heat. And so that's certainly a connection there as well.
Short Wave
The Science Behind Wildfire Smoke
And so, you know, I can only hope that people start to think about how much their lives will be changed as our climate continues to change and get warmer.