I have heard countless times the perils of global warming and how we should all do our fair share to save the Earth for future generations.
Here is but one example from an NPR article: "Global Warming is Irreversible, says Study"
"People have imagined that if we stopped emitting carbon dioxide that the climate would go back to normal in 100 years or 200 years. What we're showing here is that's not right. It's essentially an irreversible change that will last for more than a thousand years," Solomon says. [in an interview regarding a study published in the Proceedings of the National Academy of Sciences]
Makes trying to improve the state of affairs sound rather hopeless, doesn't it?
Others think that mitigating or reversing the effects of global warming might be possible:
At the US Department Of Energy's Ask a Scientist website (which I realize pales on peer review compared to PNAS...), some creative solutions are offered by a visitor and the scientists who reply:
Visitor: If we do not do enough to thwart Global Warming, and the oceans start to rise, could we use the effects of Nuclear Winter to offset global warming? Of course we would have to be careful about radiation and radioactive contamination by using the cleanest possible nuclear devices.
Reply by Marc Frenau: This is a good question, but fortunately you do not have to use nuclear bombs to put the dust and particles in the atmosphere. The idea is to reflect sunlight back to space and you could do this by putting lots of sulfur particles into the atmosphere. You do not need dust from nuclear explosions, you could just use rockets or supersonic transports or whatever to get the sulfate particles up to the correct height in the atmosphere....
Reply by Don Libby: Actually, some scientists (e.g. Reid Bryson at the University of Wisconsin) believe that there is sufficient dust in the atmosphere already to effectively counter any global warming effect from C02...I wonder if we could not provide the shade with less potential harm than nuclear explosions would cause, such as putting a huge tarpaulin into earth orbit to create a solar eclipse.
While I'm not sure I'd bet on manufacturing a tarp to blot out the sun, is it scientifically reasonable to doubt the irreversibility of global warming?
Couldn't there be some present or future technological countermeasure to global warming that would make it reversible, not irreversible?