For the Ozone Layer, a New Look By THE NEW YORK TIMES Is the ozone layer healing? Satellite observation of the hole that developed over Antarctica in the mid-1980's shows that it has split in two and has shrunk considerably since last year, making it the smallest it has been since 1988. But federal scientists say the condition is most likely temporary and probably has nothing to do with the international ban on chemicals that deplete the ozone layer, which shields the planet from harmful solar radiation. The hole, actually a broad area of low ozone concentrations caused by chlorofluorocarbons and other synthetic compounds that destroy ozone, forms in September and October. At its peak this year, it covered six million square miles, down from an average of nine million over the last six years. But this is probably because of an unusual confluence of events, said scientists at NASA's Goddard Space Flight Center in Greenbelt, Md., in particular, warm temperatures around the edges of the vortex of high-altitude winds at the pole. In late September, stratospheric turbulence split the ozone gap into two lobes, a condition not seen since satellite observations of the atmosphere began in the early 1970's. Still, the outlook is favorable. With long-lived ozone-destroying chemicals banned under the Montreal Protocol of 1987, the hole should shrink and disappear by 2050 or so, scientists say.
I wouldn't count on that just yet Ref, give the Republicans a little more time to get us back on track for global desruction.
Definitely two very different things. Scientist at your service here, for better or worse. We are definitely continuing to add the so-called "greenhouse" gases, like CO2, to the atmosphere and there's no doubt that the effect could become run-away, because once an atmosphere starts warming, it will automatically have a greater capacity for holding water vapor, which contributes to further warming, and so on and so on. 99% of scientists not on oil company contracts will tell you this, and that's as good an agreement as you get on any scientific topic. It's the straight dope basic thermodynamics. The ozone problem can't be simplified in the same way, because it's not just a heat balance issue. There's so many process paths for ozone to come and go ... Basically both issues have this in common: our pollutants are a factor, a negative factor, and you can then simply argue the extent of our role in the equation. 1) CFCs and their kin will contribute to ozone depletion in the upper atmosphere. Other processes will too, and you can argue the *extent* of a human effect, but the chemistry is basic, and there will definitely be an effect. 2) Greenhouse gases are better at absorbing sunlight than other gases and therefore elevated levels of the greenhouses gases automatically give greater heat input to the system that is Earth's atmosphere. Again, you can argue *extent*, and again, there are other factors in the overall thermal balance of our planet (like solar variability). In both cases, our behavior is a factor. You're welcome to work through the data and argue that it's a minor factor in one case or the other, but I take issue with people who say that human activity is not a factor. Sorry for long boring post -- button pushed. Routine executed. Now I can sit down again.
I think the scientific reason behind this happening is that the earth's surface decided it wanted to look more like Spiderman's mask.
I don't think he means breathing necessarily. Methane is a prime culprit, and (sorry again Azadre, but quit reading this thread if you know all this already) cows are the world's #1 source of it. Maybe mrpaige is giving them a run for their money.
What kind of scientist if I might ask? I am curious becuase as a scientist I have never really felt the urge to say "I am a scientist so I know what I'm talking about". I usually say something like "I am a chemist" or "I minored in biology" if I want to convey having knowledge of those fields. "Science" is way too broad imo to be applied to all of these fields equally. It's all a matter of significance. If human activity contributes less than 0.1% of all greenhouse gasses (and I'm not saying that's the number; I just made it up) then I think it's safe to say we are not a factor. Technically it's not true but it's a matter of practicallity.
Dylan, Biophysicist, and I never typed that I knew what I what I was talking about. My understanding, however, and I'm very interested in these topics, is that the people who research them understand the processes fairly well. I've looked at a number of primary research articles on global warming evidence, and I think I follow them. Maybe not. Your example using, say 0.1%, is a great one. But until we understand the exact nature of equilibrium in the atmosphere (many would argue this may never happen; we still have very little idea of the exact role of the ocean exchanges, for instance), I'm not sure we can semantically ever say that even a tiny negative effect is insignificant, or "not a factor." Maybe that logic is flawed. It just seems to me that, if we agree a certain effect is negative, it would be smart to do whatever we can to minimize that effect (within reason, mrpaige, so you do what you have to do). I know it's much more complicated than that, once you intersect this with economics. But some people are complacent with the attitude similar to "well, I only smoke one cigarette per week, and that probably won't give me cancer, right?"
I remember reading 0.5% CO2 atmospheric accumulation is caused annually by humans. Basically, the article I was reading said humans relativily small contribution of CO2 was throwing off the mass balance and causing accumulation.
