Geochemists from the United States, New Zealand, and South Africa gathered 573 sediment samples and 124 sediment cores from different fjord systems across the world, and in specific, it seems that fjords in Alaska and Antarctica are the most effective in capturing carbon and keeping it in before it is expelled into the atmosphere before it is converted into carbon dioxide.
In a report published on the journal Nature Geosciences, the researchers referred to fjords as “hotspots of organic carbon burial, because they receive high rates of organic material fluxes from the watershed.” But on the other hand, a separate report from the journal/science blog Nature claims that the possibility of fjords being used as carbon sinks has not been thoroughly analyzed until now, as their small surface area makes them hard to map. On the new study, it does prove that fjords are very effective in capturing carbon, being capable of capturing 18 million metric tons annually, or 11 percent of the carbon that gets buried underneath the ocean. That’s not bad at all, considering that fjords make up a microscopic 0.1 percent share of the world’s oceans.
University of Edinburgh professor Stuart Haszeldine talked further about the issue in an interview with Wired UK, saying that even with fjords capable of capturing so much carbon, 11 percent is still a very small percentage, keeping in mind all the carbon that gets buried underneath oceans. He also said that he isn’t quite sure yet why Alaskan and Antarctic fjords are more effective than those in other parts of the world – this is one reason why more research may be needed.
“There may be speculative ideas on how to enhance the storage of organic carbon in these fjord sites, for example by deliberate disposal of biomass into these deep stagnant waters, so that acts as a reduction of atmospheric CO2 after the biomass has recaptured CO2 from the atmosphere,” said Haszeldine. “However, any such engineered disposal action will require much more work and understanding of the deep seabed ecosystem impacts, and will require national legislation to be enacted.”