Climate change is happening. What should we do about it?
With climate change, we can expect serious consequences, including destruction of coastal communities by sea level rise, increased frequency of deadly heat waves, and worsening of crop-decimating draughts. Many of us have been hearing the same story for years: we need to cut carbon emissions drastically and immediately prioritize the planet's health… over corporate interests and long standing convenience. Hmm, seems difficult.
Human greed is no easy thing to overcome, unfortunately. So what other options do we have? Could we perhaps look to science to get us out of this mess?
Science to the rescue. It's a lovely idea, isn't it?
We burn fossil fuels without abandon, the Earth keeps heating up to the brink of disaster, and then a team of scientists and engineers, perhaps adored in shining armor, step in and save us from the brink of destruction. Thanks to them, we get an intact planet with the extra-sweet bonus of never paying a price for our unmitigated greenhouse gas emissions!
Well, there are brilliant minds working on this: they're called climate engineers, or sometimes geoengineers. And their work is picking up serious attention.
In fact, some scientists suggest that the warming targets outlined in the 2015 Paris Agreement are can only be reached with geoengineering technologies.
Could this be our solution? Can we bank on scientists and geoengineers to cool down the planet?
Climate engineers take two different approaches to take charge of the planet:
- by reflecting the solar radiation that would otherwise heat the Earth back into space;
- by taking greenhouse gases out of the atmosphere.
But, is geoengineering our way out of climate change realistic?
Approach 1: Too much sunlight heating us up? Just bounce it back where it came from!
The excess greenhouse gases, like CO2, in the atmosphere are trapping too much heat, but what if we didn't have to worry about as much heat entering the atmosphere in the first place? This is the main idea behind the other, and more controversial, concept for engineering our climate.
Solar geoengineering involves reflecting solar radiation back into space, or enhancing the Earth's albedo, with the idea that the Earth cannot continue warming without extra heat, picture a giant space mirror (which have actually been suggested).
Some of practical methods for enhancing the Earth's albedo include the release of reflective aerosols into the atmosphere or brightening the clouds by spraying seawater into them, which reflect radiation rather than allowing it to be absorbed by the Earth. When it comes to messing with the sky, though, scientists can't yet confidently predict its impacts. There is large uncertainty on the effects of changing the earth's albedo, and implementing such geoengineering methods may have unpredictable, and perhaps irreversible, results. While geoengineering may address incoming heat, it's only a Band-Aid for the larger disease: too much CO2
Approach 2: Too much carbon in the atmosphere? Let's just get rid of it!
We are releasing a lot of CO2 into the atmosphere, which is trapping heat and causing the planet to warm. It would be a lot easier if scientists could just remove the CO2 that we produce. Well, here, scientists are looking to nature for a solution. Just as trees convert CO2 into solid organic material for up to hundreds of years, many geoengineers are focusing on ways to sequester carbon from the atmosphere.
These methods range from planting vast forests, to using renewable (plant or plant-based) biomass energy plants which capture the CO2 given off for bio-energy with carbon capture storage (or BECCS).
Unfortunately, carbon sequestration is expensive, and untested on a large scale, and sadly, it has to be implemented on a huge scale to have any major impact. Even worse, when we inject our carbon into rocks deep below the surface to forget about it, we may run the risk of leaks through rock fissures if we don't use the right rocks. Finally, as CO2 emissions increase,there may simply not be enough land available for BECCS to save us, especially if we wait decades to implement it.
So can we rely on climate engineering to save us?
Climate engineering may be a powerful and possibly necessary tool for us in the future, but relying on it now is a precarious mindset to have, in part due to the limitations and uncertainties listed above.
It's also important to note that overstating our confidence in these technologies retains the moral hazard of telling polluters that what they're doing is okay- that there will be no consequences for their destruction. With immediate and drastic reductions of CO2 emissions, that gold-standard 350 parts-per-million of CO2, the level we must achieve to avoid irreversible climate change, may still be a possibility. On the other hand, some scientists argue that even under most optimal circumstances we will be unable to keep temperatures from continuing to rise without geoengineering.
Scientists are not superheroes, however- there are some problems that may not be fixable. People are asking whether we can truly science! our way out of climate change in lieu of changing our lifestyles. Above are two of the best approaches to geoengineering, which are both admittedly still problematic- but they're what we've got. Are you willing to accept these solutions and their uncertainties? Or, should we change our lifestyles while we're still within the window when mitigation without geoengineering could be possible?
Hilde Oliver is a PhD student in the Department of Marine Sciences at the University of Georgia, where she studies how extreme melting of Greenland's ice sheet is impacting marine ecosystems. Hilde is a huge fan of Korean food, yoga, and campy movies. Hilde currently serves as an Associate Editor for the Athens Science Observer and is on the Athens Science Café Programming Board. Follow her on Twitter @Hilde_Oliver or shoot her an email at hildeoliver@uga.edu. More from Hilde Oliver.
