I guess whomever will be doing the research will, as most researchers still do, consider the Earth as a "rock". While the fact is, it's a rock which is covered by life, and life is very significant in thermal and chemical regulation of the surface of this planet, among other things. Therefore, i quite expect the research to produce incorrect results, which then would be used by decision-makers to make, err, decisions about whether to do geoengineering or not. Darn, the term itself is wrong, even: when people talk about _geo_engineering, processes they are thinking about is not enough geoengineering at all, but rather about _gaia_engineering, i.e. the engineering of biosphere and inanimate matter which is directly next to living beings - in yet other words, about Earth surface, and in particular, parts of it which are inhabitable (by humans and/or organisms, including but not limited to organisms humans have a direct use of - forests, farms, oceans for fish, etc).
Those would-be "geo"engineers are trying to tinker with a real, very existing system - Gaia, in terms of James Lovelock, - without understanding how the system actually works. Most of them don't even know that
- forests are regulating their leaves' temperature, keeping it constant no matter how cool or hot nearby air is - much like human body is keeping its own optimal temperature in rather narrow boundaries;
- many green plants, including some of most important marine green plants, can only function in optimal mode if both intensity and wavelength pattern of incoming sunlight is within rather narrow boundaries, - namely very close or same to what it has been for last couple millions years. When the nature and/or intensity of sunlight changes significantly, - efficiency and productivity of green plants suffer in a rather complex way noone yet fully understands; yet we do know it's very significant from some research which was done about effects of reduced intensity of sunlight on agriculture crops. On a planetary scale, any major change in sunlight's composition and/or inetnsity is likely to cause very massive and, probably, very damaging consequences, among which would be a major change in thermal equilibrium of living systems, both marine and land-based (and those systems are a major part of Earth total surface);
- any "geo"engineering project which, by a coincedence or effort or both, would allow to prolong, somewhat, the existance of currently functioning global industrial fossil-fuel-based civilization, - would in effect prolong all the negative impacts of said civilization as well, including but not limited to: ongoing massive soil degradation, erosion, further increase of artificial chemicals and pollutans levels, destruction of natural ecosystems via deforestation, overfishing, wetlands' removal, further loss of species, further development of dangerous contagious cross-species diseases in huge industrial agro-complexes (both plant and animal, possibly cross-species to human like swine flu and such), further depletion of useful (to man) minerals and ores and many other effects, most of which are damaging to Earth's living beings.
But no, they won't think about it. Fixed on temperature, aren't we. Keeping the Earth under +2 degrees C increase on top of pre-industrial is all we can dream of, eh?
I am sometimes amazed how extremely formal and unimaginative many "specialsts" and "governments" and "agencies" are. Look at them, they talk big time about "controlling global warming". "Limiting" it. And they pretend that by doing so, they'll be able to solve the problem.
Would they?
See, imagine a man who gets to the doctor and says: "Doc, i am really feeling very sick, please, help me". Imagine that's because that guy has more than a dozen serious diseases, each being potentially lethal. Then, what would you think the doctor would do? Would he just measure the patient's temperature, and if it's more than 2 degrees C above normal, give him some pills which are known to drop body temperature by force? And if the Doc does just that - would you think that our imagined guy would survive?
Life on Earth is that guy, and some folks in National Academy of Sciences, in CIA, in NOAA etc - apparently think that some "administrations" together with some "corporations" and "governments" now existing, - are together what would work as Earth's "doctor", willing and able to cure the sickness. While the fact is, it's quite possible they would do only harm, just like a doctor who's be only forcing patient's temperature to go down - because for quite a number of human diseases, fever (increased temperature) seem to increase the chances of survival (or shortening the duration of the general sickness for less-deadly cases):
http://en.wikipedia.org/wiki/Fever#Usefulness . So, while we're at it, - if you ever get a fever, then do NOT take antipyretics (pills which force body temperature to go down), - unless you got really good doctor who knows what he's doing and says that the fever just must be reduced/stopped due to other factors he is aware about.
I'll hope that those "geo"engineers will fail at implementing more of silly measures (some, they already are doing, what with all the Al2O3 sky-high surface concentrations and patents about aluminium oxide in jet fuel; the thing is some ~4 times more effective at reflecting "desired" wavelengths than SO2 &Co).
