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In July 2012, a ship floating off the coast of British Columbia dumped 100 tons of iron
slurry into the pacific ocean. With this massive injection of iron into the water, the crew,
led by the eccentric entrepreneur Russ George, sought to create an algae bloom that would
not only capture carbon but also spur the growth of salmon in nearby coastal fisheries.
Fisheries that the Haida Nation hired Russ George to replenish. The result? A surge in
salmon population the year after that patch of the ocean was fertilized with iron, and
for Russ George, a firestorm of scientific and public backlash that illuminated the ethical,
political, and ecological consequences of these seemingly silver bullet solutions to
climate change and environmental collapse. The Russ Georges of the world continue to
champion these magical techno-fixes as the path towards stopping climate change. So today,
I'm going to unpack the consequences of these silver bullet solutions with two questions:
Are silver bullet solutions realistic? And if they aren't, why do we continue to pursue
them?
Silver bullet climate innovations span the sci-fi-sounding spectrum of ideas from launching
mirrors into space to the holy grail of clean energy: nuclear fusion.
That's my fellow YouTuber Adam Levy, who runs the amazingly informative channel ClimateAdam
and also happens to have a PhD in Atmospheric Physics. As Adam just mentioned, there are
a lot of seemingly magical fixes to climate change, but today we are going to narrow in
on two specific case-studies of these climatic “solutions” that help illuminate how and
why we seek out fast-fixes for climate change.
The first is bioenergy with carbon capture and storage also known as BECCS. Simply put,
this technology transforms organic materials such as paper pulp, crops, or bycut from logging
industries into energy via fermentation, combustion, or gasification. There are a range of technologies
under the BECCS umbrella, but all seek to capture CO2 released during the energy creation
stage then store that captured CO2 into underground aquifers or dried up oil wells.
Thanks to the bioenergy in BECCS, CO2 is absorbed by the plant matter fuel as it grows. And
when this fuel is burned, thanks to the carbon capture and storage, this CO2 is - well - captured
and stored. The appeal is that BECCS technologies take more CO2 out of the air than they put
in. And because we've delayed cutting emissions for so long roughly 90% of IPCC projection
scenarios point towards significant use of BECCS to help us remain below 2.0° C. In
theory, BECCS sounds like a great plan. After all, you're stopping emissions at the source
and the biomass that you use is also capturing carbon. In other words: negative emissions.
But, in practice, BECCS is not the silver bullet solution that it seems to be. One large
obstacle for the large-scale implementation of BECCS simulated in the Intergovernmental
Panel on Climate Change's scenarios is land use. According to a briefing from the Grantham
Institute, models that use BECCS to remain below 1.5°C could require the equivalent
of 25-80% of our current cropland in order to grow enough biomass to replace current
fossil fuel production. Even if we used just 20% of our current cropland, we would have
to use the equivalent of all the land in Australia to satiate BECCS's demand for biomass.
Such huge land requirements would inevitably drive land use change, potentially resulting
in deforestation, biodiversity loss, and loss of carbon sequestration from natural sources
like trees.
Granted this is very much dependent on context. In the short term countries like the U.S.,
which has a comparably mature bioenergy infrastructure, could use existing agricultural and logging
waste to fuel this endeavor. But in order to scale up BECCS in the long term in line
with the IPCC scenarios, this technology would require a massive amount of land for biomass
specific crops.
The levels of BECCS in these simulations would require much more than agricultural waste
alone. Eventually, farmland will need to be diverted to specifically grow crops for BECCS
use, which means additional fertilizer use, additional trucks transporting biomass to
energy plants, and a heavy strain on fresh water resources to the tune of 0.72 to 24.4
billion metric tonnes per year. To put that in perspective, global agriculture's total
water consumption right now is close to 8 billion metric tonnes per year. And growing
fuel instead of food could cause at least as many problems as it solves.
It's important to keep in mind that, like almost all silver bullet solutions, BECCS
has yet to be tried at a massive scale. Although we shouldn't write it off completely for
its shortcomings, we need to recognize it's easier to implement it in a climate model
than it is in reality. There is still a lot we have to study and figure out before we
begin to heavily rely on it. That being said, out of all the silver bullet solutions proposed
in the last couple of decades, BECCS is one of the more reasonable and achievable. But
there are some that are straight out of a sci-fi movie.
With that we turn to Solar Radiation Management or SRM. In short, solar radiation management
is used to describe a range of methods that seek to reflect sunlight back out of the atmosphere
to reduce global temperatures. SRM solutions include reasonable and achievable ideas like
reflective paint on roofs but they also incorporate proposals like the highly imaginative space
mirrors that would orbit around the earth.
And one solution in the middle of that spectrum is stratospheric aerosol injection. Essentially
this silver bullet solution attempts to mimic the natural phenomenon of volcanic eruptions
by injecting sulphate aerosols into the upper atmosphere. These tiny molecules would create
a reflective blanket around the Earth, artificially cooling the climate.
But, does this method actually work?
Yeah, it seems like it would, although no one has conducted a real world experiment
with stratospheric aerosol injection. But researchers can study natural experiments
after big volcanic eruptions. The aerosols from these do indeed cause the Earth's temperature
dip for a year or two. But even though these aerosols would be pretty cheap to manufacture
and inject, this cooling would come with substantial hidden costs.
He's right, according to one paper on stratospheric aerosols, the cooling effect could cause a
global shortage of rainfall, especially in summer monsoon regions, droughts, increased
air pollution, acid rain, and the possible depletion of the ozone layer. Sulfate aerosols
only stay in the atmosphere for 1-3 years, which means that constant injections are needed
to maintain the cooling effect. If the method was ever suddenly halted, one study predicts
we would experience rapid temperature and precipitation increases at 5–10 times the
rates of our current global warming trend.
Considering that our current governing bodies can barely agree on emissions targets, it's
hard to imagine the world agreeing on a consistent delivery of aerosols into the atmosphere.
Especially since the costs and benefits wouldn't be shared equally across the globe.
And alongside all of these issues, stratospheric aerosol injections could be used as an excuse
to continue burning fossil fuels and increasing emissions. Which might be part of the reason
why Silicon Valley thought leaders and billionaires alike find such an appeal in these silver
bullet solutions.
“The path to success is going to require innovation across every one of these sectors.
In my experience innovation can do magical things.”
Bill Gates is right. Innovation is important. But these innovations must be pursued in conjunction
with the myriad of solutions already available. We must seriously tackle emissions reductions
before we try anything else. Because as climate blogger and physicist Joe Romm notes, some
of these silver bullet solutions are akin to using “a dangerous course of chemotherapy
and radiation to treat a condition curable through diet and exercise — or, in this
case, emissions reduction.” But reducing emissions could necessitate a transformation
away from a society that makes billionaires like Bill Gates rich. This then, might be
the reason why we cling to silver bullets. The distant hope of an easy answer allows
us to continue our present actions. That is especially the case for companies and capitalists
who profit off of our current emissions catastrophe.
When we bet on “miracle” solutions like sulfate aerosols, we choose the highly risky
but seemingly straightforward to implement option over a low risk but transformative
one. Emissions solutions like renewables can offer decentralized, clean energy for billions
of people around the globe, while free, electrified transportation infrastructure can pull millions
of gas guzzling cars off our roads.
Yes, these answers might have to fight an uphill political battle to be implemented,
but they exist here and now and bring a whole lot more equity and democracy to the table
compared to pouring sulfur gases into the stratosphere. If we do indeed need BECCS to
stay under 2 or 1.5 degrees, it can't be the full picture - only one single piece of
the bigger puzzle. The answer to mitigating climate change will never be found in one
miracle technology, we have to use the multitude of answers currently in front of us, from
electrified trains to decentralized solar to the redistribution of food waste if we
want to mitigate climate change quickly. We can't wait around for new tools to mature
to start dealing with climate change, we need to begin drastic economic and social transitions
now to create a zero carbon future. A future that is environmentally ethical and just where
we don't have to dim the sun in order to live.
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Hey everyone, Charlie here. If you haven't already, I'd highly recommend heading over
to Climate Adam's channel and hit the subscribe button and then watching the video we made
together all about Nuclear Fusion. Adam's channel is awesome, and brings some much needed
levity to the climate change conversation. Hope you're doing well and I'll see you
in two weeks!