posted
Help! I've done a lot of research, taken notes, and am now ready to cry out to some hopefully sympathetic ears for the following - even pointing me to a book or site would be appreciated
1) Say our atmosphere has more and more CO2 in it. How much saturation would be required for breathing outside to be less desirable, but still adequate for life and growing things? People should be able to adapt to this level, but not want to unless forced to.
2) Would the air be changed in any way our senses could detect?
3) What might be the initial effect on a person unused to being outside for long periods of time (such as dizziness)?
posted
IIRC, the CO_2 level in clue human blood is about 15%. If the level in the air reaches that, osmosis will no longer remove CO_2 from the bloodstream. It will then form carbonic acid, which can be fatal.
At lower (but still elevated) levels, CO_2 probably causes dizziness, lightheadedness, and exhaustion, but I'm not sure.
CO_2 cannot be seen or smelt, but it is possible to feal when your longs are not working proberly.
I think normal CO_2 in Earth's atmosphere is about 1%.
posted
If our atmosphere had enough CO2 in it to make most humans noticibly uncomfortable breathing it, it would be at the fatal level for a significant percentage of the population, both human and other animal. Plants would be completely unaffected, as they make more than enough oxygen to provide for the tiny amount of respiration they need.
Osmosis refers to any solvent, not just water. But yes, diffusion is probably a better term, though in this particular case the correct term would probably be gas exchange.
There are no noticible effects before you get impaired, it isn't even slightly uncomfortable to breath air with a moderately high amount of CO2, and most people find it has a calming effect (this is the origin of the ancient practice of breathing into a paper bag, for instance).
If there were about 10% CO2 in the air, that would be enough to make most people feel pretty darn lethargic (and pretty calm), but it isn't actually uncomfortable (though some people will die--just not very many). Some animals would be worse off than others, plants (as mentioned) would be fine, even like it.
But it would be catastrophic for the weather. Not even the most pessimistic Global Warning crack-pots play with projected levels of CO2 anywhere near that high. Anyone speculating about raising atmospheric levels of CO2 above 4-5% is universally regarded as a fruit-loop. The one percent figure Narvi recalls is for all gasses besides nitrogen and oxygen (though CO2 does head that list of other gases by a fair margin).
So in simple terms, I would say the answers are 1)primary error, no correct answer to question as stated 2)not unless people were dying 3)lethargy, then dizzyness, unconsciousness and death.
quote:But it would be catastrophic for the weather. Not even the most pessimistic Global Warning crack-pots play with projected levels of CO2 anywhere near that high.
I understand that recent research suggests CO2 might not have as much effect on global temperatures as was previously thought. I can't remember the reference, though, so I have no idea how good the research is...
posted
CO2 being heavier than oxygen should fall down to the ground. Unless I'm mistaken, excess CO2 would be a big hazzard for the living things on the ground.
I think California (Los Angles) has a problem with the smog (which does include quite a bit of CO2). Since none of the exaust fumes rise they cover the city and surrounding area.
So I would believe that increasing the CO2 in the atmosphere would keep the concentration near the surface and cause havoc with the life. I'm not sure how it would effect the weather.
posted
I believe that what Survivor is refering to is the fact that CO2 is a greenhouse gas. Such a drastic increase in any greenhouse gas would in turn, drastically increase the trapped heat at the surface of the earth. This would cause flooding due to ice caps melting as well as increased inhospitible zones for plant growth.
Posts: 1621 | Registered: Apr 2002
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posted
It has been demonstrated that local CO2 concentrations can have a strong effect on the local weather (this is the reason for "smog-potting" to protect orange groves and some other types of crops from early frosts). The reason that man-made CO2 may not have as much of an effect globally as predicted is because it turns out that man-made CO2 doesn't account for most CO2 in the atmosphere...natural CO2 production from volcanic action and forest fires are the main source of atmospheric CO2. In addition, it turns out that even slightly warmer temperatures with a higher CO2 concentration extend the growing season (see smog-pots) and increase precipitation (see water cycle) as well as increasing the CO2 available for plant growth. Thus, if there is double the CO2 in the air, the rate of carbon draw-down from plant life is approximately doubled or more as a result. This means that it is actually quite difficult for humans to make a significant difference in CO2 levels (unless we simply deliberately burn everything in sight for no reason--which does happen sometimes).
Smog includes CO2, but the important compounds in smog are all various nitrogen componds which are toxic at very small concentrations. These nitrogen componds are also responsible for 'acid rain' and the visible layer of brownish air capping the inversion. Normally, CO is more important to smog than CO2, since it is far more toxic and cannot readily be eliminated by natural processes. CO2, on the other hand, doesn't have that much of a tendancy to cling to the ground except when produced in truly impressive concentrations, almost always as a result of volcanic activity (well, really more always as a result of volcanic activity).
posted
I hear that in order to reach their target for reducing CO2 emissions that was part of the Kyoto summit a few years back, New Zealand was considering introducing a tax on sheep - almost half of their greenhouse gas emissions come from them, largely in the form of methane...
posted
First: is this going to be yet another dystopian future story? I'm sick of those. Maybe it's just me, though, and the general population eats them up like candy.
Second: Survivor: IIRC from biology, CO2 in the lungs is responsible for your panic response when you "run out of air" (as opposed to the absence of O2). Also, I can't seem to find any reference of ancients having ready access to paper bags.
This seems to suggest that its actually CO2 dissolved into the blood that controls when you need to breathe, so in a higher CO2 environment, people would probably be prone to hyperventilation.
Actually, this could be handy for a scene I wrote for my novel a couple of months back, gotta go back and reevaluate it from this perspective. I think, by chance, I actually got it right :-)
quote:There are no noticible effects before you get impaired, it isn't even slightly uncomfortable to breath air with a moderately high amount of CO2, and most people find it has a calming effect (this is the origin of the ancient practice of breathing into a paper bag, for instance).
quote:This seems to suggest that its actually CO2 dissolved into the blood that controls when you need to breathe, so in a higher CO2 environment, people would probably be prone to hyperventilation.
There seems to be a conflict here. Hyperventilating people are not calm.
[This message has been edited by Kolona (edited November 05, 2003).]
posted
No contradiction, you don't experience panic until your blood CO2 rises to the impairment level. You start hyperventilation after you become dizzy, start to fade out, ect. ect..
If you have enough CO2 that a significant number of people are hyperventilating, then a lot of people are going to be dying. Also, children can't develop normally in levels of CO2 that high, so the entire population will be retarded.
Rebreathing your own CO2 does generally have a calming effect, though currently it is not recommended that you put a bag on someone's face when they're panicking (that's why I refer to it as an 'ancient' practice--I thought more people would find that funny).
posted
ARGH! Browser crashed, lost reply, must start over... never think to save bb stuff - my mistake.
Thank you all for your contributions - I really appreciate it. I've done some better searches - sometimes I think the research is more seductive than writing, a bad trap. I had come across a reference to the acrid taste of CO2 at a certain concentration, but could not find what that was. I imagine it is much higher than what I am working with.
In response to ps, if you go with a strict definition of dystopia then I guess you could say the story will run on those lines... I'd like to think what I do won't be typical. The "what if" surely starts there, as I am tired of short-sighted people and seeing more cement and less trees everytime I travel home. I know that the current CO2 level is about .035% (350ppm), and could go to .07% (700ppm) by 2100, so even shooting for 1% atmospheric concentration would be pushing it! But we still have, for many reasons, increasing CO2, leading to warming, which will affect biomass sensitive to that, creating a loss of more biomass... There is a threshhold for biomass to take in CO2, beyond which it cannot take in more (back to something Survivor mentioned)... so there will be consequences to our actions (burning of finite fossil fuels, agricultural impact, etc., along with things we can't change like volcanos!) but I will go with our ability to fix things - I'm into Disney endings! Not that there won't be a twisted plan working against the positive ending. All of this does help with the people who will live outside (no, no domed cities!), and I won't forget to consider altitude with CO2 being heavier than air. I think I've read so much about getting the science right that my writing is bogged down. I've already rewritten my first chapter 4 times (not just edits) and it has gone from a short story to, well, more.
I probably had this all worded better, but now it is late and I'm tired. Thanks for being there! -Lee
posted
If you want to do a global warming story, then do a global warming story (just not Waterworld, okay?).
If you want to have pollution in the air, then just have actual pollution. You know, methane, sulfer dioxides, nitrites, stuff you can smell and see.
Just for the record, most of our 'biomass' prefers warmer temperatures than are normal in our currant climate. It is a sharp decrease in global temperatures that would lead to significant die-offs in terms of 'biomass', a warming trend would only kill certain rare 'niche' species.
Just on my own hook, I would avoid such a patently trendy cause as CO2 based global warming. Trendy science fiction is...well, it isn't a good thing.
posted
Ok, not only did Netscape crash (is this XP related?) again, but I had been copying my post and THAT was gone too... driving me nuts.
I'm researching background for a world that exists after experiencing some significant effects from global warming. I've done enough reading to know it is reasonable. I'm not worried about us getting cold (I hate the cold!). Most of the background would never make it into the story - it helps me set up scenes and motivations, etc. I hope I'm writing more about the characters who are in this milieu, as opposed to the idea being the main point. I would not want it to be Waterworld - but it would be soggy about the edges.
As for pollution - that was not really the intention (as in smog, acid rain) - I just wondered if we doubled the CO2 (or more) in the atmosphere if it would affect people living outside (other than weather effects, etc). I don't think it will. I'm looking into other possibilities as well.
From my reading, I understand that some forests will like more CO2 to a point (and more warmth) and increase the rate of growth, but that will be temporary. Some part will not like it, die, and contribute more to warming, which will affect some other part... the viscious cycle. If the phytoplankton at the top of the ocean grows rapidly, what happens to what is below? Mostly, the world has already experienced the problems of gw, but people are working to fix things when something goes wrong. I'm interested in those who want to fix things and what they are doing, and in people who work against that and why they would do so. Ok, this is really general. Maybe this will just be my thousands of words of crap, but I won't know until I've done it. I do have a journal where I'm trying to generate more fresh ideas (not truely original obviously, as if I could I'd be rich!), but I want to start somewhere. More importantly, I'd like to finish something!
If there are stories like this I would love to know their names so I might read a couple - and no I don't want to watch Waterworld again! I don't want to be trendy - I just want to write an interesting story. I haven't personally read any stories like this - I'm sure they are out there, I just haven't found them.
Thanks - it helps to have comments that make you think about what you are doing.