There have been some suggestions that
global climate change, when or if it happens, could be reversed by (advanced) technology.
Terra-re-forming if you like. This obviously applies to
global cooling as well - and explicitly does not count simple technology designed to
reduce gas emissions (I suppose). It's also irrelevant whether the change is natural or human change. What are the options?
- Chemistry : Ca(OH)2 Scrubbers
The 31 March 2001 issue of New Scientist reports on a proposal published in Geophysical Research Letters (like you care :) to chemically scrub the atmosphere. Vast chemical ponds - described as an 'artificial "superforest"' (which kind of begs an obvious question...) - absorb the carbon dioxide (not, of course, any other types of greenhouse gases). The CaCo3 is then heated to tranfer the CO2 to magnesium silicates, which are then buried. Where you bury enough MgSi to absorb 7 billion tonnes (7 trillion kilograms) of carbon dioxide, I don't know. Obviously, the ideas can be refined - such as using tree like structures to get a better surface area to volume ratio (again, that nagging question...). - Biology : Seeding
No, not forests (presumably) but fertilizing the oceans to, basically, promote algal blooms. Since algae make a significant carbon sink contribution anyway this is working with the system rather than trying to replace it. A controversial possibility - since our understanding of the climate is, well, tenuous. That probably applies to all these 'solutions'. - Nanotech : Er...
After I stopped laughing when a noder suggested this in a writeup (I'm not going to hardlink, find it yourself) I reluctantly considered how this could work. Ignoring the simple possibility of using existing, sophisticated, carbon filtration devices (see biology, above) you could construct nanoscale machines to break down CO2 or absorb it or...polymerise it into a vast woven net to advertise in the sky. Whatever, the devices would have to be constructed from something and be catalytic to catch a significant proportion of unwanted gas.
Warming is a lot easier (solar mirrors and so on) but I'm not sure how useful these anti-warming strategies are. All the ones I've listed are 'closing the barn door' approaches - surely it would be much simpler to not release as much gas in the first place. Plug those volcanoes! Even if human activities are only adding to the problem, we still don't want it warm. Reducing emissions rather than cleaning up afterwards just seems more sensible. Correct me if I'm wrong.