posted by Matt Owens March 22, 2013
Allan Savory has a solid head on his shoulders, in no small part because of the remorse he carries from helping kill 40,000 elephants. If that sounds like a lot, it is, but then there used to be a lot more. So it wasn't back then. Kind of like those elephant herds, grasslands around the world have been rapidly shrinking, turning to desert. But Savory has figured out a way to stop and reverse a lot of this using novel herding techniques; considering this would also provide food and income to millions, it's pretty genius if it can be made to work.
Above: Savory gives a TED talk in February of this year; run time is about 30 minutes.
Greenhouse gas emissions come from not just burning of fossil fuels, but also from the way we use our land. Carbon dioxide gets consumed by plants an incorporated into their corpus, or tissues, if you will. A part of this then gets eaten by herbivores or dies and gets eaten by microbes and fungi and whatnot - only to become soil, along with the carbon. Only a small portion of the plant material that gets produced each year becomes soil carbon, but it builds up. The amounts of carbon that could be stored in restored grasslands' grasses and soils is pretty decent.
Savory is not big into carbon budgets by self-admission, so before anyone gets too excited, let me assure you, he hasn't found the cure for climate change - unfortunately his idea would only pull 6 or 12 years worth of human emissions (at present rates) out of the air and store it as grass and soil. His idea makes no real impact on our society's bad habit of living half a world away from where we work, shop, and play; or on our just-as-bad habit of buying products and services provided via fossil fuel use. It's a complicated issue for sure, but Savory has found at least one part of one possible answer.
Looking at the latest IPCC report's estimates of carbon pools, I see that reclaiming about half of the world's deserts and semi-deserts, assuming they can be transformed to tropical savannah conditions, would pull about 120 GtC (gigatonnes of carbon, not to be confused with GtCO2) out of the air. That's a huge amount, although only about 60 GtC would come out in short order, into the vegetation. The rest, another 60 GtC or so, would take decades or longer to build up as stored carbon in the soil. For comparison, current human emissions are about 10 GtC per year (and climbing).
This is definitely a handy arrow to have in our quiver. So what's stopping us from turning the deserts green? Where are the funds for land managers or educators? Where's the initiative for robotic herders (that one may be a stretch, but do you want to herd all those goats around all day)?
Photo Credit: Alex E. Proimos, via Flickr.