Geo-engineering (or terraforming the Earth) is one option we have for responding to massive environmental crises, especially climate change. If we do not respond quickly enough to the need to cut greenhouse gas emissions, it may be one of the only strategies with which we are left. That said, there is increasing consensus that it's a pretty unrealistic strategy. Given our extremely limited understanding of (and thus ability to manage) the planet now, with more modest expectations and under comparatively stable conditions, debating geo-engineering may even provide a stalking horse for climate "skeptics":
"The knowledge that we maybe could engineer our way out of climate problems inevitably lessens the political will to begin reducing carbon dioxide emissions," observes David Keith from the University of Calgary in Canada...
Ken Caldeira [of the Department of Global Ecology at Stanford] agrees that geoengineering is, for the moment, a tempting but illusory quick fix to an intricate system; a much less problematic solution, he says, would be to change our lifestyles by reducing energy consumption and CO2 emissions.
"I think the Earth's system is so complicated that our interfering with it is very likely to screw things up and very unlikely to improve things," he says. "And this is the only planet we have."
"I think the Earth's system is so complicated that our interfering with it is very likely to screw things up and very unlikely to improve things,"
Probably. I like it to dorking around with an operating system or application when you don't have man pages or a decent understanding of what is going on under the hood.
"And this is the only planet we have."
This is true now. It will not always be so.
I think that's true for most of the ideas out there. But there are some cleanly-reversible options - giant space mirrors reflecting away sunlight, for example, could easily have mechanisms in place to pull the mirrors out of orbit and away from the planet if we wanted rid of them later.
But there are some cleanly-reversible options
I'm iffy about that. If I jazz the heat on my stew (and it smells pretty good right about now, yum yum) it will cook faster ... but the bottom will burn and I'll have char on the bottom of the pot. Not so yum yum. I can take off the heat but the damage is done.
Right - simplisitc analogy but hey .. it's lunch time and stew sounds really good for dinner.
The problem with even reversible planetary-scale engineering projects, I suspect, is not primarily technical, but political.
If a space mirror costs multiple billions, how much political inertia will adhere to its use? We have situations where the science is comparatively unequivocal -- burning oil heats the planet; certain chemical harm human health -- but where sustained lobbying/PR efforts on behalf of an industry which would be impacted by change has prevented the science from being ackowledged as a basis for policy change.
Engineering the planet would demand not only more advanced scientific knowledge than we are yet capable of, but also a completely different relationship between science and politics. I think the latter is far more difficult than the former, and to ignore it is to be living in a dreamworld.
Which is not to say that making use of our better understanding of the planet to intervene at strategic points is a bad idea, only to say that we should be doubly cautious.
Consider the system. At what POINT would there be agreeement to put up, for eg, giant mirrors? Life on earth would have to be pretty screwed up by then, otherwise how would such an idea get approval or budget? Better prevention than an attempted cure after the disease has taken hold.
This is about the public's understanding of climate disruption, and of the time scales in which we would decide to pursue policies. Warning - it's profound, but depressing:
If worst comes to worst, we would probably reengineer ourselves and plant/animal life to the new climate conditions, rather than geoengineering as such.
I'm not at all confident, personally, that we have the ability (much less the wisdom) to do that well, Michael.
Given how complex and fraught with potential disaster even transgenic agricultural bioengineering has proven, I'm not sure we will at any point in my lifetime but ready for serious GM work on an ecosystem-wide basis, which is what you're essentially proposing. We don't understand DNA well enough, we don't understand ecosystems well enough, we don't understand climate well enough and we know next to nothing about the interactions of the three.
Not to mention that the task of bioengineering all of life to new conditions makes going cold turkey on carbon look easy.