Big Risks of Geoengineering

So, if unprecedented violent storms, disastrous droughts, and catastrophic sea level rises are part of the cost we'll pay for a couple of centuries of anthropogenic climate change, maybe we should consider geoengineering as part of the solution.

It's always tempting to look for quick fixes from powerful new technologies, like molecular manufacturing. But, as we have noted before, simply having a technology available does not insure that it will be used wisely, or even used at all:

What will it really be like when exponential general-purpose molecular manufacturing is achieved?

Will it result in an explosion of powerful new products? Will it bring a new Industrial Revolution overnight to previously undeveloped areas? Will it change everything?

Or might it perhaps be a more "ho-hum" evolutionary development, significant but not especially transformative?

Computer data moves at the speed of light, nanomachines will do a million physical operations a second, but people still think and move at a pace evolved for life on the savanna.

And beyond the question of how quickly these new technologies will be adopted and applied is whether they might end up doing more harm than good:

Using radical techniques to "engineer" Earth's climate by blocking sunlight could cool Earth but presents great risks that could well worsen global warming should they fail or be discontinued, reports a new study published in the June 4 early online edition of the Proceedings of the National Academy of Sciences.

Using computer simulations to model the impact of proposed experiments using a solar filter to block sunlight instead of reducing greenhouse gas emissions, an international team of scientists conclude that geoengineering a risky strategy.

“Given current political and economic trends, it is easy to become pessimistic about the prospect that needed cuts in carbon dioxide emissions will come soon enough or be deep enough to avoid irreversibly damaging our climate,” said co-author Ken Caldeira of the Carnegie Institution’s Department of Global Ecology. “If we want to consider more dramatic options, such as deliberately altering the Earth’s climate, it’s important to understand how these strategies might play out.”

That's from a new online article at Mongabay.com, which goes on to say:

The PNAS study shows that geoengineering schemes, even under a scenario of increasing emissions, could cool Earth within a few decades to pre-Industrial Revolution levels, but that failure of the system would result in "a catastrophic, decade-long spike in global temperatures... with rates of warming 20 times greater than we are experiencing today" as carbon sequestered in plants and soils would be quickly released into the atmosphere."

“If we become addicted to a planetary sunshade, we could experience a painful withdrawal if our fix was suddenly cut off,” said Caldeira. “This needs to be taken into consideration if we ever think seriously about implementing a geoengineering strategy.”

Caldeira said that proposed geoengineering schemes need to be better understood before they are implemented but that the quick-acting nature of the projects mean that can put off geoengineering decisions until they become absolutely necessary.

“I hope I never need a parachute, but if my plane is going down in flames, I sure hope I have a parachute handy,” Caldeira said. ”I hope we’ll never need geoengineering schemes, but if a climate catastrophe occurs, I sure hope we will have thought through our options carefully.”

We certainly agree with that. As CRN Global Futures Strategist Jamais Cascio said a few weeks ago:

Should geoengineering be required, it should be done as carefully and as reversibly as possible. More research into geoengineering is especially important in order to know what not to do.

If climate disaster hits faster and harder than anticipated, desperate people will try desperate measures, including geoengineering. We need to be able to identify the choices that won't just make things worse.

Mike Treder

Tags: nanotechnology nanotech nano science technology ethics weblog blog

Comments

[Nato Welch]

Wouldn't it be better to tackle the problem closer to the source, by just trying to take the carbon out of the air?

[Mike Treder, CRN]

Yes, it would seem to make sense to pull carbon from the air, perhaps in a scheme something like we suggested here. But I doubt that will do enough by itself to reverse or sufficiently retard warming events already in motion (e.g., Greenland, Artic, and Antarctic ice melts). Some ambitious efforts probably will have to be made to shade portions of the earth while we work on reducing emissions and also try to lower the greenhouse gas content of the atmosphere.