Could 3D seaweed farms save our climate and heal our oceans?
Seaweed farming appears to be getting a lot of attention lately. No sooner do I read about kelp as the new kale in the New Yorker that I pick up Tim Flannery's new book, Atmosphere of Hope which, alongside advocating a massive ramp up of clean energy and efficiency, pushes solutions like seaweed farming as a "third way" technology that could significantly reduce atmospheric carbon emissions, mitigate ocean acidification and other marine pollutants and also provide habitat for threatened sea creatures. (Flannery's book covers a lot of other "third way" technologies, but I'm half way through—so let's stick with seaweed for now.)
It's definitely an intriguing proposition. From offshore wind installations doubling as seaweed farms to kelp being marketed as a substitute for bacon, TreeHugger has gotten on the seaweed train before. As Margaret reminded us too, seaweed can also help fight fertilizer run-off—sucking up excess nitrogen from our bays and sometimes even being returned to the field as fertilizer.
It's fascinating stuff, but can it be made to work in practice? Here's a Scientific American video about Thimble Island Ocean Farm, where former commercial fisherman Bren Smith is busy making up for his previous actions by cultivating a polyculture of kelp, oysters, scallops and mussels in what he claims is a low carbon, regenerative model that could help heal our seas.
Flannery's book suggests that covering something like 9% of the world's oceans with seaweed farms could sequester the equivalent of the entire world's carbon emissions one day. (This appears to be the research he is citing.) Whether or not such systems can or even should be brought to that kind of scale remains to be seen. Still, on a smaller scale Smith's work looks a whole lot better than the gigantic industrial trawlers that are currently delivering our seafood. Just one more example of farming that seeks to not just be less bad, but to actually heal the earth too. Take a look, it's pretty badass.