That said, the air inside the cabin isn’t that fresh. “It smells like you’re flying over a campfire,” said Palm. “It’s an interesting science because the reactions are happening right in front of you. And you are measuring them happening in real time in the atmosphere. “
To understand what the team found, we must first talk about gasoline and sugar. Put a little bit of gas on the road and you’ll smell it right away, because it’s very volatile – it evaporates quickly. In other words, it doesn’t want to stay Concentrates. On the other hand, the sugar is in the bowl on your table, not volatile, so it will solidify. Atmospheric scientist Joel Thornton, co-author of the University of Washington said: “You don̵7;t really worry about your sugar evaporating. “Over time, it’s a more sticky molecule, much less volatile.” Sticky in this case means molecularly sticky – if you put a lot of oxygen into a molecule, you get more durable and less volatile bonds.
And there’s a lot of oxygen to go up in the atmosphere. What Thornton and Palm discovered was that the molecules in wildfire smoke also stick with time, like sugar, in a freezing sense. More specifically, the smoke is loaded with carbon from burned vegetation, oxidized in the atmosphere. “The addition of oxygen to this carbon backbone makes the molecule in the atmosphere more sticky and more likely to be in the condensation phase, like sugar,” Thornton said.
This means that elementary particles – which come directly from a forest fire – can produce secondary particles in the fire by chemical reaction. The team can measure this on an airplane with a device called a mass spectrometer, which calculates molecular weight. There are probably tens of thousands of organic compounds in wildfire smoke – phenols, for example, including hydrogen, carbon and oxygen. In the atmosphere, these phenols are oxidized, collecting more oxygen, and thus becoming more sticky, developing into particles over time.
At the same time, the beam of smoke dilutes as it moves with the wind. Some of the compounds evaporate away, and particles fall out of the bristles and land on the ground. “Then you can also have the organic gases undergo reactions add Palm said. “So you have competing processes going on that are affecting the amount of particles, organic particles, that are transported with the wind.”
That is, the beam of particles simultaneously dissipates and accumulates new particles through chemical reactions. That’s very important when we consider human respiratory health, because particulates from wildfire smoke work deep into the lungs. These researchers did not point out which particles may be of the most concern, but scientists do know for sure that wildfire smoke is not good for respiratory health. In particular, they are concerned about particles known as PM 2.5 (particulate matter 2.5 microns or smaller) that could irritate the eyes and nose and exacerbate existing chronic heart or lung problems. have. They may contain heavy metal solids such as lead and cadmium, and polychromic hydrocarbons, some of which have been linked to cancer.