According to an important new study, the glacier-carved fjords found all across the globe from Alaska to Antarctica are significantly better at capturing and storing carbon than other open-water marine systems. This new information comes from a University of Florida study published on Tuesday, May 5th in the academic journal Nature Geosciences.

New Study Says Frozen Fjords Hold 11% of Oceanic Carbon

Statement from researcher

“Carbon sequestration is the big buzzword, but we’re still getting a handle on how it works,” explained Thomas Bianchi, a geochemist from the University of Florida who participated in the research. He pointed out that for making informed land-use decisions and accurate climate predictions, “finding and understanding these hot spots is critical.”

Details on the new study of fjords and carbon sequestration

Richard Smith, a postdoc fellow at the University of Connecticut, was the project leader, and the team included researchers from New Zealand, South Africa, Tulane University and the Woods Hole Oceanographic Institution.

The study highlighted that although fjords are only a small fraction of the total ocean, these cold, deep waters store 11% of the carbon trapped in the  world’s oceans. According to the study, Fjords lock away an estimated 18 million metric tons of carbon a year. When it’s absorbed by the ocean, it cannot convert to  carbon dioxide, one of the greenhouse gases that leads to global warming.

The high efficiency of fjords at storing carbon related to their deep, narrow shape, which means that carbon sinks down into low-oxygen zones where it is not consumed much by aerobic bacteria. This means the carbon does not re-enter the atmosphere as carbon dioxide.

Of note, scientists have been aware for quite some time that that fjords allowed for high carbon storage, but given that fjords only represent one tenth of a percent of the total global oceans, the critical importance of this marine environment was not recognized until now.

The researchers analyzed samples sediments from fjords in New Zealand, then compared them with earlier data from the Arctic, sub-Arctic Canada, British Columbia, Norway, Sweden, Scotland, Greenland, Svalbard, Alaska, Chile and Antarctica. Surprisingly, it turns out that fjords are 500% more efficient at carbon sequestration compared to continental shelves, another area of the oceans where carbon is commonly buried.