Human Activity Warmed the Planet, Could it Cool it too?

The easiest and ideal means of curbing climate change and global warming is reducing global carbon emissions. Though earlier efforts like the Kyoto Protocol failed to gain unanimous support, there is an increasingly urgent call from leaders and nations around the world to take unified action. This is, without a doubt, promising. As is the Democratic bill now in Congress that would mandate a 20 percent cut in greenhouse gas emissions by 2020 and 80 percent cut by 2050. But what if it's too late? What if we miss, or have already missed, our chance to halt the warming of the planet? Is there anything else that could be done?

Recently, John Holdren has led discussions in the White House about just such a scenario. The talks have been about "geoengineering," or methods humans could use to force the planet to cool. It sounds like science fiction but many revered scientists, including Nobel Laureate Paul Crutzen, think that human intervention may be a viable solution to human-caused global warming.

Holdren, who is himself a MacArthur Foundation "genius" grant recipient, outlined two possible geoengineering solutions. The first would shoot sulfur particles into the upper-atmosphere, simulating the cooling effect of a large volcanic eruption. The second would require the construction of large artificial "trees" that would absorb and store carbon. Holdren pointed out that either of these methods could have serious consequences and would only be considered if the situation got dramatically worse.

Which brings us back to the easiest and ideal means of curbing climate change: reducing global carbon emissions. The burden falls on governments to establish international emissions limits, on industry to shift to more responsible modes of operation, and on ourselves to change our eco-unfriendly behaviours. In the end, it will take a large-scale international effort to reverse the damage that has already been done, but starting at home is the first step. Hopefully this will solve the problem before more dramatic, and potentially dangerous, solutions are attempted.