Geological engineering, more commonly referred to as geoengineering, involves the deliberate large-scale manipulation of environmental processes. Geoengineering was proposed as an option to combat climate change as far back as Lyndon B. Johnson's presidency in 1965 and, in recent years, has become synonymous with climate engineering. Some view this approach as an ingenious way to rectify mankind's exploitation of Earth, while others see it as humans dangerously addressing problems rooted in the anthropological manipulation of nature with further human intervention.
One of the most commonly debated geoengineering projects to fight climate change is oceanic iron fertilization, also known as carbon sinking or ocean seeding. The goal of iron fertilization is that the intentional injection of iron into the upper ocean will stimulate the growth of phytoplankton, which will draw atmospheric carbon dioxide into the ocean. Then, when the phytoplankton die they can sink to the bottom of the ocean and sequester, or store, the absorbed carbon.
Some proponents of iron fertilization theorize that the addition of iron into the Southern Ocean could reduce atmospheric carbon dioxide levels by 15 percent. Certain supporters, such as the Haida Salmon Restoration Corporation, also believe that it could also increase certain fish yields, such as salmon, which could counteract overfishing and boost the seafood industry.
However, critics worry that the introduction of iron can have unpredictable and destructive impacts on marine ecosystems. Furthermore, some scientists have found that phytoplankton blooms in the Southern Ocean can increase the production of calcium carbonate shells by other marine organisms, which is a process that actually produces carbon dioxide. This would offset some of the sequestered carbon dioxide associated with the sinking phytoplankton. Now we must contemplate: are the risks associated with iron fertilization worth the potential reward?
Another controversial geoengineering method is the pumping of aerosol sulfates into the stratosphere to magnify the effect of global dimming. Ideally, the sulfate aerosols would form a layer in the stratosphere and reflect a portion of the sun's radiation, reducing the amount of energy reaching the lower atmosphere and Earth's surface.
The Council on Foreign Affairs estimates that "just one kilogram of sulfur well placed in the stratosphere would roughly offset the warming effect of several hundred thousand kilograms of carbon dioxide" and would have a fairly quick impact on the climate. The need for only existing technology also makes it a feasible cost-effective method. Furthermore, volcanic eruptions and certain other natural processes produce stratospheric sulfate aerosols naturally, allowing scientists to better observe their impacts.
However, others fear that the use of stratospheric sulfates can actually hurt the environment and put people at risk. Many studies show that the shielding effect of aerosols would alter precipitation patterns and reduce rainfall, likely causing droughts. The diffusion of sunlight can also impact plant life and solar power. Moreover, certain scientists worry that the use of sulfate aerosols can actually deplete the ozone layer and worsen our environmental situation.
The bottom line is that no one fully understands how these geoengineering approaches to climate change would impact the environment or local ecosystems, especially in the long-run. Some people, including American entrepreneur, Russ George, who dumped one-hundred tons of iron off the coast of Canada in July of 2012 without any supervision or government approval, want to rush these projects into action. However, rash actions like this can actually exacerbate the problem or spark a whole new set of issues. More research needs to be done on the efficacy and secondary effects of each approach before they can be used in the real world on a large-scale. Supporting these types of projects or not is your choice, but whether you believe that geoengineering is ingenious or short-sighted, steps need to be taken to mitigate global warming.