As I mentioned previously I have been trying to decide on a charity for this year's fundraiser and having some trouble deciding. Ultimately I realized that what I am most interested in funding is not climate change mitigation, but reversal. Estimates tell us that 350 parts per million CO2 is about what is "normal" or would maintain current temperatures on Earth. Well unfortunately we are at 400 ppm and still climbing. So even if we suddenly halt all emissions, there will still be fallout from the amount of CO2 currently in our atmosphere.
“Want to skip the research and just donate to the cause? Fair enough. Click on the picture below to redirect to the donation page.”
There are several ideas for CO2 emission reversals out there. Quite a number of them revolve around geoengineering, which just sort of sounds cyber-punky and sci-fi ish for a thing so serious. But nomenclature and branding problems aside, we will need to come up with a way to mitigate anticipated temperatures (aside from generally advising people to not by land near a flood zone). A number of these seem a bit outlandish or even dangerous - imagine if some sort of solar reflector suddenly failed!
One option that stuck out to me for it's relative simplicity, viability and minimal potential fallout was using soil as a carbon sink, otherwise known as soil carbon sequestration. Despite this not being something I had heard of previously there is fairly extensive research on the topic.
So what is soil carbon sequestration?
Or how do you pump carbon into the ground
Long answer:
Explained by the Knowledge Project here, however
tl;dr
Abbreviated answer:
It is the circle of life.
Don't start singing yet. It turns out that this circle is exceedingly complicated, but there is a lot that we know that can help us understand the potential impact of carbon sequestration into soil.
If you recall your last botany class (otherwise known as the "plant" chapter in your high school biology textbook) plants live by using energy from the sun and carbon in the air through photosynthesis, and by drawing nutrients and water up from the ground through their roots. It is through this intake of carbon during photosynthesis that stores the carbon in plants. The plants then shed biomatter, their roots decay, or they die which all decomposes into humus, the organic (carbon rich) part of dirt.
Carbon balance within the soil (brown box) is controlled by carbon inputs from photosynthesis and carbon losses by respiration. Decomposition of roots and root products by soil fauna and microbes produces humus, a long-lived store of SOC.
© 2012 Nature Education
However the process of this decomposition involves fungi and microbes that eat the biomatter and then expel (you guessed it) carbon. So one of the key parts of creating good carbon sequestration is making sure you are doing it in a climate that has lots of plant growth, but slow decomposition and fungal growth. This all sounds simple(ish), but it turns out that natural systems are incredibly complex and have lots of moving parts, which means there are lots of factors that need to be taken into consideration when attempting to create a biological carbon sync. I mean, like a whole hell of a lot of factors.
Because the botanical circle of life is so complex it is still unclear if carbon soil sequestration is a sufficient or viable solution to climate change mitigation.
However it does seem promising enough to warrant further research and investment.
So there seems to be a lot of potential in carbon sequestration through improved agricultural practices (C sequestration rates of 0.6 to 1.2 Gt C/yr in cropland coils), which would also lead to increased crop yields to support a growing population. That being said one of biggest carbon sinks we currently have are our rain forests (with a potential of 0.8-1.0 Gt C/yr through afforestation in tropical forest ecosystems). This brings me back to an original recommendation I read when starting my research: CoolEarth.
The number listed above in the Virginia Tech study is about afforestation, whereas CoolEarth works on preventing deforestation. While I couldn't find any hard data on the amount a current living rain forest could additionally sequester, prevention is also good because deforestation isn't just pulling down ecosystems and habitats it is actually knocking down current carbon sinks! Aaak!
Did I mention that these are very complicated systems and a very crowded space?
While I feel like I have become far more knowledgeable about ecology, and how agriculture, forests, and human interventions can impact climate change, I still don't feel completely confident in saying that any one avenue is the most impactful option to slow, prevent, or mitigate climate change. I do think that further research and knowledge aggregation of current data has the potential to be very effective. But again, I lack the confidence to back any particular horse to get this job done.
Stepping back
So what did I glean from all of this? My main takeaway is that there won't be a single silver bullet to climate change in our (foreseeable) future. It will have to be an aggregate effort to:
- curb and end emissions
- to create renewable and reliable energy sources
- to enact policies and incentives that encourage innovation and adoption, both individually and in industry
- increasing international cooperation and trust
- improve agricultural standards and practices
- protect, and rebuild forests
- and probably a load of other stuff I've forgotten or don't know about
In lieu of checking off all of those boxes I think that ultimately donating money to an organization that has proven to do good transparent work is a good place to start. So I've decided to collect donations for CoolEarth. They have been fairly consistently rated as a top charity working on climate change. They are not only transparent with their operations, costs, and outcomes, but are relatively cost effective. They also have a more tangible, measurable outcome than investing in research or policy work.
Through all of my research into carbon sequestration I have an added admiration for the complexity and importance that our botanical world plays in mitigating and reversing climate change. So I've decided that given only foggy paths forward in removing carbon already in our atmosphere, it is best to invest in retaining the current natural carbon sinks we already have.
Oh, and did I mention that since CoolEarth works with indigenous populations as the primary way of preventing deforestation there is a load of social, educational, health, and economic benefits they create also? The GWWC estimate of £0.84 per tonne of greenhouse emission, but I would be interested to see what the adjustment of that number, plus the social belefit would be in cost per QALY.
Last but not least, who is their primary patron? Dame Vivian friggin' Westwood. This is just icing on the cake.
Very punk rock.
In the meantime if you know of or hear about any promising research or charities working on other forms of carbon sequestration or climate change knowledge aggregation I would love to hear about them.