Geoengineering is not your typical mechanical or chemical engineering. It doesn’t exclusively involve using science and math to design and build machines and structures. Geoengineering is a relatively new practice that aims to intervene in Earth’s natural systems on a large scale. Our increasing concern over the catastrophic impacts of climate change have caused the field’s emergence in the engineering discipline. Some claim that geoengineering is a thing of the future; the techniques that scientists in the geoengineering field propose will take years to develop, and will take even more years to see results. But, advocates of this new concept point out that it can be practiced by those who do not have an engineering degree. They argue that geoengineering is already in full swing…we just call it by a different name: global warming (watch Bill Nye’s video on climate change to learn more about global warming). By continuing to produce billions of tons greenhouse gases every year, we have engineered a hotter, wetter, and more unmanageable climate than what people lived in hundreds of years ago.
Greenhouse gases, such as carbon dioxide, methane, and nitrous oxide, contribute to global warming by trapping heat in the atmosphere. These gases are warming the Arctic more than twice as fast as anywhere else in the world, with one of the main consequences being rising sea levels. Here, the Greenland Ice Sheet poses the greatest threat for ocean levels because it is thawing fast enough to raise the worldwide sea 0.74 millimeters a year. According to Andrea Dutton, a professor at the University of Florida, if the entire Greenland Ice Sheet were to melt, it would raise sea levels by seven meters, enough to flood major cities like Hong Kong and Mumbai.
In order to reduce the effects of greenhouse gases on global warming, scientists are now turning to geoengineering techniques to lower the Earth’s temperature. One of the main focuses of geoengineering is reflecting the Sun’s energy back into space, which will counteract rising temperatures. This can be done by increasing the reflectiveness of clouds or introducing small, reflective particles into the atmosphere. There is a lot of potential for these forms of reverse–engineering the effects of global warming; Harvard University recently invested $7.5 million into researching them. While the idea may seem promising, the downsides of this new technology are unpredictable. What makes the issue of geoengineering particularly concerning is that there is only one test subject: the world. Can we afford to conduct such large–scale experiments on our only known habitable planet?
Although scientists agree that spraying a gas into the atmosphere to prevent sunlight from reaching the Earth can decrease global temperatures, it does not address the carbon dioxide issue. Alan Robock, a climate scientist at Rutgers University, says that geoengineering is not a solution to global warming, and will only “take away what push there is now for mitigat[ing]” greenhouse gas emissions. About half of all excess carbon in the atmosphere is taken up by the ocean; continued carbon dioxide emissions would only increase the severity of an already thirty percent more acidic ocean than it was before the Industrial Revolution. Ocean acidification poses a serious threat to the entire oceanic biological chain, from marine microorganisms all the way up to humans.
Not only can these aerosols undermine current efforts to reduce greenhouse gas emissions, but they also only have temporary effects. One of the most discussed options is injecting sulfate particles into the atmosphere, but they only last for one to two years before they fall out of the air. There is no denying that sulfate particles have a significant cooling effect; in 1991, the volcanic eruption at Mount Pinatubo in the Philippines released twenty million tons of sulfur dioxide into the atmosphere. The Earth experienced a cooling of 1 degree Fahrenheit, but only for about three years, as the particles began to go away, taking the cooling effect with him. The eruption also caused ozone depletion, allowing more ultraviolet rays to reach Earth, increasing the risk of skin cancer and cataracts in humans and animals.
Other than the fact that aerosol injections have already been proven to lower global temperatures, supporters of geoengineering counter these previous arguments by claiming that it will be cost effective. Harvard professor David Keith says that geoengineering would cost just ten billion dollars, which equates to one tenth thousandth of global GDP. The benefits could be more than one percent of global GDP, a return of one thousand times greater than the costs.
Michael Wolovick, a post–doc at Princeton University, has also found a way to address the issue of cooling only certain regions while also preventing droughts in others. He proposes to regulate rising sea levels by building walls at the mouths of unstable glaciers to regulate their response to the warming ocean and atmosphere. Wolovick’s research could possibly make glaciers last up to ten times longer.
Although we as individuals may not be able to directly contribute to projects such as aerosol injection and Wolovick’s glacier research, we can still reverse the effects of climate change by reducing our greenhouse gas emissions. One of the main issues people have with geoengineering is that it will discourage the world from participating in environmentally friendly habits. However, if we stay conscious of this, we could be able to simultaneously reduce greenhouse gas emissions and implement geoengineering techniques.
References:
https://www.theatlantic.com/science/archive/2018/01/a-new-geo-engineering-proposal-to-stop-sea-level-rise/550214/
https://www.livescience.com/6095-raging-debate-geoengineer-earths-climate.html
http://www.geoengineering.ox.ac.uk/what-is-geoengineering/what-is-geoengineering/
http://climate.envsci.rutgers.edu/pdf/20Reasons.pdf
This topic is extremely interesting. I would love to follow this research, now, to see what sort of progress is made. I am fascinated by innovation and am curious to see how this plays out. I wonder what kinds of technology will exist in the future to combat problems such as global warming. The concerning part though, is to imagine the new problems that will arise due to these advancements. I think of progress as a whack-a-mole game. It seems that in the process of solving one problem, another is created.
Wow, this is a really interesting post. As an architecture major, I am really interested in green energy, green design, and reducing the effects of global warming. It’s scary to think that the only way we can test the new geothermal techniques is by using our planet as a test subject. We won’t be able to reverse the process once it’s been done, which puts a lot of stress on the engineers in charge. I assume the entire world also has to come to a consensus if we do something like this. Most of the countries in the world have to agree on geo-engineering in order for us to actually do it. Otherwise, we may start a large scale conflict about this kind of technology.