“And by the way, [geoengineering is] not really a moral hazard, it’s more like free riding on our grandkids.”
—David Keith 

Some people suggest that we won’t be able to reduce our emissions enough to avoid a planet-wide catastrophe. Indeed, Nathan Gillett from Environment Canada has studied the issue extensively and came to the conclusion that even if our emissions dropped to zero tomorrow, our planet has trapped enough heat in the oceans, and the carbon dioxide lingers in the atmosphere long enough that we wouldn’t see any improvement in our global warming for another thousand years.

For this reason, there’s talk out there among some groups that the real solution isn’t so much to attack the problem at its source (i.e. by reducing emissions), but to deal with the problem after it’s already in the air. The concept is known as geoengineering, also sometimes referred to as climate engineering or climate intervention. It’s defined as “the deliberate large-scale intervention in the Earth’s climate system, in order to moderate global warming.” (That’s to help differentiate from what we’ve already done to the climate which wasn’t deliberate and which caused global warming rather than moderated it.)

There are two broad categories that are considered.

1. Carbon Dioxide Removal, or CDR. In other words, let’s remove greenhouse gases from the atmosphere. This is also frequently described as “scrubbing.” For example, carbon dioxide filters were used in the Apollo modules for the astronauts who had to spend days exhaling carbon dioxide into a closed space. CDR is similar, although on a much grander scale. A few of the ways this can be done is to burn biomass for energy rather than fossil fuels, because they’re easily replaced with new crops, unlike fossil fuels which take millions of years to generate. Another option is to consider ocean fertilization with agents such as iron, helping boost phytoplankton and increasing photosynthesis in the process. Carbon capture and storage may be a part of this overall plan as well. In principle, most of these methods are designed to speed up Earth’s natural Carbon Cycle.
2. Solar radiation management, or SRM. This one tries to add something to the atmosphere that will help reflect some of the sun’s radiation and thereby prevent as much from reaching Earth’s surface. One option is to sprinkle saltwater particles into clouds, making them whiter and, therefore, more reflective. Another is to try to make Earth’s surface more reflective by painting roofs and roads white, and even considering large desert reflectors. One method follows the example of volcanic emissions by adding aerosols into the stratosphere, helping cool the planet overall. The last major volcanic eruption that led to such a noticeable effect was Mount Pinatubo in the Philippines in 1991. The global temperature dropped a half-degree Celsius that year. (I’ll never forget it because that summer was when I got my first new car, a Mazda Miata. Despite having a ragtop convertible, it was awful. We didn’t hit 30 degrees Celsius in London, Ontario once that entire year.) Finally, there’s the option of putting solar reflectors into orbit, preventing the radiation from reaching the planet before it even gets to the atmsophere.

There are so many hurdles to overcome with these concepts that at this point they’re nothing more than pipe dreams. First, there’s the expense of such grand schemes. Second, there’s the unknown of possible unexpected outcomes such schemes might lead to. Third, none of these have been proven to be effective enough to help the problem to any reasonable degree at this point.

Despite these obstacles, some people believe geoengineering could be a valuable component of tackling the problem in addition to strategies that minimize emissions. Of course, if strategies to mitigate the effects of adding greenhouse gases to the atmosphere are in place, it may well lead some people and some industries to make less efforts to reduce those emissions, so we may not be any further ahead in the long run.

Research will no doubt continue into geoengineering for years to come. I’d certainly favour a strategy of scrubbing carbon dioxide over injecting something into the sky to increase the albedo of our atmosphere. Some of the strategies that have already had some preliminary research include iron fertilization and adding sulfur aerosols into the stratosphere. Both have a long way to go before being considered viable options, however.

Not that I agree with everything James Lovelock has to say on climate change—his predictions have been off more than once in past years—but I do like his perspective on the subject:

“Before we start geoengineering we have to raise the following question: are we sufficiently talented to take on what might become the onerous permanent task of keeping the Earth in homeostasis? Consider what might happen if we start by using a stratospheric aerosol to ameliorate global heating; even if it succeeds, it would not be long before we face the additional problem of ocean acidification. This would need another medicine, and so on… Whatever we do is likely to lead to death on a scale that makes all previous wars, famines and disasters small…”

When I was in San Francisco a few weeks ago to receive training from Al Gore and the Climate Reality staff, the question of geoengineering came up. Mr. Gore discussed the issue and then gave this analogy:

Imagine you’re stranded at sea in a lifeboat with a group of people. At one point, some of the poeple at one end start to rock the lifeboat, gradually more violently to the point where there’s a real risk that the boat will capsize and everyone will drown. One solution is to ask the people to stop rocking the boat. (That would be like reducing our emissions.) Another would be to use a mirror and try to communicate to someone on shore, letting them know the frequency and the amplitude of the waves being created by the rocking lifeboat. Those on shore could then construct a large wave machine that would be designed to try to precisely counteract the waves from the boat, helping to smooth out the water so that everyone in the boat would remain safe. (That would be like geoengineering.)

Seems to me that both Dr. Lovelock and Mr. Gore are right. If we’re going to make any real progress in solving the problem of greenhouse gas emissions, global warming and climate change, then it’s time we got peope to stop rocking the boat.