(no subject)

[sci8fi.livejournal.com]

My friend is doing NaNo this year and needs a little help with her plot but she doesn't have a LJ account and I don't know the answer, so I thought I'd pose this question for her:

Is there/could there be a reason for the Earth's atmosphere to become unbreathable?

If so, could this happen in only a few parts of the world?

Thanks for any help you can give. Hope those word counts are rising!!

Comments

[irish-injun.livejournal.com]

Since there is greater pollution in some cities than others, it strikes me that it might be possible. I don't see how it would remain contained to one area, though, but so far there are rural areas that aren't polluted...so if it's something in the air itself, there's a chance elevation or distance might make a difference.

[janenx01.livejournal.com]

This was my thought. Polluted air is heavier, isn't it? So it might not be affected by wind currents to the extent cleaner air is?

What if certain cities were polluted so much the air was unbreathable, but the air in other areas was only moderately crappy? That seems possible to me.

[irish-injun.livejournal.com]

I'd run with it. I would accept it as true if I were reading a story, and that's all fiction is...a believable lie. Go for it!

[arwensouth.livejournal.com]

Umm, I hate to tell you, but it's air. It circulates. And something catastrophic enough to cause the atmosphere to become unbreathable by humans (i.e., a massive meteor strike like the one that is believed to have caused the extinction of the dinosaurs) is not likely to be confined to just a few select places. Even something more localized, like a volcanic eruption, might make the air unbreathable or at least mighty unpleasant for a few days, but it's not going to have a long-lasting effect.

Think of it as a swimming pool. If someone pees in one end of it, would you still want to go swimming in the other end? It might be okay initially, but eventually, the pee is going to circulate throughout the entire pool and it's going to be everywhere. Though it'll be more diluted, if that helps.

[dvoid-03.livejournal.com]

Basically, pollution is your best bet for localized toxic air. In fact, Asia's got a real world example for you: http://seattletimes.nwsource.com/html/nationworld/2008389439_browncloud14.html

"For those who breathe the toxic mix, the impact can be deadly. Henning Rodhe, a professor of chemical meteorology at Stockholm University, estimates 340,000 people in China and India die each year from cardiovascular and respiratory diseases that can be traced to the emissions from coal-burning factories, diesel trucks and kitchen stoves fueled by firewood."

If some countries in your friend's novel had an even more concentrated toxic mix, not only would more people be dying faster, but the sun-blotting, plant killing effects would probably be worse, too. Which would further wreck the air quality.

[melanyebaggins.livejournal.com]

SMOG! Cities like LA and Toronto are already horrible with Smog, it could be that in some future those levels become toxic.

Also, I used to watch the show Dark Angel (anyone who remembers/watched it gets a cookie). There was a disaster in one section of town, now called 'Terminal City' which made the entire area of, I think, ten city blocks, uninhabitable and toxic to normal humans. I think it had something to do with bio-hazardous material and/or toxic chemicals that were being experimented on at the time of the explosion/disaster/whatever.

Hope this helps! :D

[jem0000000.livejournal.com]

A friend owns Dark Angel on DVD, but sadly, I was only able to borrow it long enough to see the pilot and first three eps or so. I'll have to borrow it again when I have time to finish it....

Can I have a cookie anyway?

[themournfulduck.livejournal.com]

Realism, pfeh.

[jem0000000.livejournal.com]

Many large cities already have unbreathable atmospheres. ;)

Volcanoes and nuclear explosions generally cause the area around the event to become completely unbreathable; the area of effect gradually spreads, although in both cases, generally enough stuff hits the upper atmosphere that rather than spreading out in a nice circle, it spreads over and down in a sort of umbrella-y effect that can hit the other side of the world relatively quickly. The effects are reduced the farther away you live, but a large volcanic eruption can play havoc with air quality all over the world. Smog and other enviromental pollutants cause smaller effects, generally localized on the polluting thing, but often require a maintainance of the pollution to maintain it (ie, if all of the people doing the polluting stop, the smog will eventually disperse). The wildfires in the western US have an intermediate sort of effect: I live in the eastern US, and my asthma will flare up a week or so after one of the larger multiweek wildfires starts. A few days after it's over, my asthma slowly returns to its normal well-controlled state. I've heard other people complain about the same problem. Apparently enough of the smoke gets into the atmosphere to mess with sensitive people on the other side of the continent.

One solution is to hypothesize a heavier-than-air gaseous chemical that cannot be breathed in without killing people, and have it spilled in the area you're trying to make unbreathable. But this would only cut off an area near the ground, and you would have to stop it along elevations (mountains, maybe a very tall, unbroken wall). (The way it works, the gas would spread out along the ground. The air, which is lighter, would be pushed up by the pressure of the gas. Eventually, they would form two layers, with the gas occupying as much space as it had the pressure to push the air out of (the more gas you have, the more space you can cover), and the air lying on top of it. There would be some intermingling, particularly along the line where they joined, but you could plausibly keep it down to a minimum. The heavier stuff would continue to spread underneath the air until it ran into an object that it could neither go around nor permeate. (Most buildings would eventually be permeated, although they might slow it down. Mountains are your best bet, but it can spread through caves.) Failing something stopping it, tho, it would keep spreading along the ground, eventually forming a very wide but very thin layer. At this point, you could conceivably walk through and breathe *above* it, depending on how much of it got mixed in with the air (if even a little can kill you, this is less likely).)

Or, you could hypothesize that sometime in the future everyone on earth develops something similar to smog-induced asthma, so no one can live in smog-y cities.

I don't know if you've seen the air-quality measurements in the newspaper? They rate the qulity of air from green to red, with green to yellow being good to okay, yellow to light orange being sensitive people should limit their outdoor activity, orange being sensitive people should stay inside as much as possible and normal people should limit outdoor activity, and red being everyone should stay in as much as possible. (I think, anyway. It's been awhile since I had a newspaper subscription.)