It’s taken long enough, but the the political consensus in the United States is finally shifting towards acceptance of the existence of some sort of climate change. Nevertheless, politicians and climate researchers (not to mention the public) still widely disagree about the cause (anthropogenic disruption versus natural cycles) and extent of the problem. While the EPA has made admirable strides under President Obama towards developing U.S. sustainability initiatives, it has often been hamstrung by the politicians. This keeps the country mired in antiquated energy and environmental policies. This disagreement unfortunately characterizes not only the U.S. debate but that of most other advanced countries as well. As such, there is a serious possibility that greenhouse gas emissions will not be curbed on any reasonable timescale. In response, many scientists and environmentalists have begun looking to another, more extreme set of options for staving off a potential global disaster, which they call geoengineering.
Many ideas for engineering the earth’s climate have arisen in recent years. Some have promise, while many others seem rather outlandish.
Some scientists have advocated “seeding” parts of the surface of the ocean with iron, so that photosynthetic phytoplankton will metabolize more carbon, fixing it into their shells as calcium carbonate. The theory goes that with the increased iron, carbon uptake from the atmosphere will increase, and the shells will eventually sink to the bottom of the ocean, creating a long-term carbon sink. Others have discussed spraying clouds with seawater or chemicals that increase their albedo (their ability to reflect sunlight), so that less solar energy can reach and warm the surface of the earth.
Another idea is to inject aerosols or incredibly fine particulates into the stratosphere in order to slightly increase the reflectivity of the entire atmosphere. The argument being that this could delay the effects of global warming by temporarily cooling the earth in much the same way that particulate matter from volcanic eruptions does.
By their very nature, these techniques are highly controversial, both scientifically and politically. They are difficult to test on a large scale, and the international political infrastructure necessary for their effective implementation is nonexistent. The UN, the closest thing we have to a global governing body, lacks the level of authority necessary to allow scientists to alter the entire planet in such a substantial way. Nations all over the world would likely object on the grounds of national sovereignty. There are many other concerns. What if it doesn’t work? How will we mitigate the potential side effects if the plan goes wrong and creates some sort of new global environmental problem? What if radical groups begin using geoengineering methods as a means of planetary terrorism?
All controversy aside, I believe that geoengineering is an extremely important possibility to consider as we go forward. Geoengineering may be our Plan B (or C), our last line of defense if we do in fact reach a climate tipping point. If we can develop a means of masking the effects of global warming, perhaps only until the international community can get its act together and cut emissions, it may be an attractive option. It is time that we begin to fund the development of various geoengineering strategies; whether or not we need them remains to be determined.