Geoengineering - is it really such a good idea?

By Sarah Piplani

Humanity is becoming desperate! Heatwaves, tsunamis and droughts have left the baffled world with poor harvest, while our increasingly warm oceans produce fewer fish year by year. Since the health and state of our planet continues to decline, some governments have finally decided that it’s time to hit the crisis button. However, as our ecosystems collapse, most world leaders continue discussing money and the economy, ignoring the planet's issues. In Greta’s words “while leaders dance around climate change as if it’s not an actual threat”, activists have noticed the evident signs of climate change. Standing on the side, watching our planet die and putting our futures at stake will not work anymore, so in the coming years it becomes more crucial to slow down climate change by, perhaps, using geoengineering. This could either undo years of selfish human behaviour, buying us a decade or two so we can reverse climate impacts, or it could wipe out humanity. 

So, what is geoengineering? Will it provide an opportunity for humans to show that they can reverse the effects of climate change? 

Geoengineering refers to upcoming technologies that could save our planet by offsetting some of the impacts of climate change. It is usually split into two categories – carbon geoengineering and solar geoengineering. Carbon geoengineering will remove carbon dioxide from our atmosphere, tackling the origin of climate change whilst solar geoengineering works by reflecting a fraction of sunlight back into space, cooling the planet. 

One geoengineering technology known as stratospheric aerosol injection involves spraying inorganic particles (e.g., sulphur dioxide) into the atmosphere to keep the sun away, and this may be a way of life in the future, but is it as good as it sounds, will it really have a positive effect on our planet? 

Around 71% of the electromagnetic radiation coming from the sun is absorbed by the earth’s surface and gets trapped into earth’s blanket, causing the greenhouse effect but the rest of it (29%) is naturally being reflected off into space. One way to cool our planet is to get less of the sun’s rays trapped in earth’s blanket, causing less warming. 

During Mt. Pinatubo’s eruption in 1991 (one of the biggest volcanic eruptions in the 20th century), millions of particles of sulphur dioxide were instilled as high as the earth’s stratosphere, and they hung around there for a while! Sulphur dioxide is a noxious, invisible gas which produces a fog of sulphuric acid droplets, and these mixed with water make giant veils. These “veils” reduced the sunlight reaching the earth by 1%, causing global temperatures to drop by 0.5 degrees Celsius. It took three years before earth’s temperature bounced back to normal. It is possible to recreate this scenario by inserting sulphur particles into the earth’s stratosphere. This might be fairly easy to do and according to one study, it may be relatively cheaper compared with the escalating amounts of money that is being spent on other aspects of climate change. By using this technology, we may be able to reduce or stop global warming, buying us time to shift away from fossil fuels. However, it’s not that simple - there are bound to be some grave side-effects. Aerosol injections could disrupt rainfall patterns, devastatingly affecting agriculture leaving billions to starve. In addition to this, during the volcanic eruption in 1991, although the acidic water veils cooled our planet, they ended up heating the stratosphere causing holes in our ozone layer. Other minerals might be less harmful to our ozone layer but more research needs to be conducted before we can be fully sure that they are safe to be injected into earth’s stratosphere. However, the damage to the ozone layer is just one of the several problems injecting aerosols could have on our planet.

As stated previously, our politicians and leaders don’t bother much about climate change and if geoengineering does work, the precious, short time we’ll have to switch to a carbon neutral economy will be an excuse for world leaders to delay further work on saving our planet. 

Humanity is continuously pumping superfluous CO2 into the atmosphere, making oceans more acidic and destroying corals. As we cut down trees and wreck habitats and ecosystems due to human intervention at a rate faster than ever, we will soon have no more “natural climate solutions” left. This will rapidly increase the amount of CO2 in our air. Furthermore, we might need to continue spraying these aerosols into the stratosphere else we could face a risk of a “termination shock”. This means that if we continue adding both aerosols and carbon dioxide in the air, when we stop geoengineering the planet would heat up faster than ever before. Such a big temperature shock in such a trifling amount of time would cause all the major ecosystems on earth to collapse before humans get the opportunity to revert the damages made. Humanity might survive but the few inhabitants would have to reside in an antagonistic world. 

Hopefully, we will never have to use geoengineering but if we do, let’s hope we have all the information necessary to use this technology without any serious after-effects.

References:

https://www.youtube.com/watch?v=dSu5sXmsur4

https://geoengineering.environment.harvard.edu/geoengineering