WC Archive

But given that many of the strategies which would fall under the rubric of terraforming would have grave consequences if they fail, many people would be understandably reluctant to embark on such efforts in any event. And if the results of too-slow or insufficient action now is bad but not catastrophic, many more people would argue that the benefits of success of these projects are outweighed by the risks of failure. If we are unable to divert the not-quite-worst-but-still-pretty-bad scenarios, but choose not to use dangerous geo-engineering alternatives, what are our options?

Setting aside dying off, the main choice is engineered adjustment. But we should be clear on what this means: changes to our own behaviors and material environments, sure, but changes to the ecological environment, as well, so as to make survival possible. And adjustment has its own implications.

Publication of a recent discovery this last week is an excellent example of what adaptation would look like, and was the proximate trigger for this short essay.

Researchers at the University of Toronto have found the genes coding for the way plants "breathe:"

The pores on the surface of plant leaves, called stomata, function like little mouths that open and close in response to cues such as light, temperature, and water availability. [...] The discovery is another step in understanding how plants respond to their environment. In hot temperatures, plants keep their mouths “shut” longer than usual, to avoid losing gases and water through evaporation. However, they must open their stomata at some point, both to pick up carbon dioxide needed for photosynthesis and to release oxygen back into the atmosphere. This new information will be important to plant breeders looking to improve crop resistance to drought, as well as to those seeking to understand plants’ evolutionary responses to climate, says Campbell.

The research was published in the July 12 Current Biology; abstract and supplemental data here.

The relevance of this discovery for our discussion is two-fold:

First, as temperatures rise, we are certain to have greater numbers and severity of droughts. Plants that might withstand a season or two of reduced rainfall would have a far harder time when the drought conditions last decades. It is highly likely that we will need to engineer crops for greater drought resistance; furthermore, as different plants now have different levels of resistance, it's likely that we'll have to do transgenic engineering, pulling the characteristics from highly-drought-resistant plants and working them into the less-resistant species. Smart breeding and traditional cross-breeding will help to an extent, but it will be hard to avoid the need for full-scale genetic modification of crops.

The second point is somewhat more subtle. The article indicates that, as drought conditions worsen, plants "breathe" less in order to maintain internal moisture. But when plants breathe less, that means that they take less CO2 out of the atmosphere. This means that droughts decrease the carbon sequestration action of affected plants and engineered adaptations to enhance that resistance would very likely further decrease sequestration in plants. This, in turn, would slow the recovery of the atmosphere to pre-disruption conditions.

This is a single, and likely minor, example of what "engineered adjustment" would mean. It's not a clear-cut case that adjustment is a safer path than terraforming, should we force our climate to the point that these become our only plausible options. As I indicated with the first Terraforming Earth piece, my goal is to get us thinking about these options now, to better understand the choices that we could face, and to use them to test the strength and weaknesses of other choices that might emerge.

In the end, though, the obvious lesson to take from all of this is that we're far better off avoiding these hard choices entirely by not letting the climate warm to disaster.