According to a press release from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), scientists have discovered a previously unidentified carbon transportation route in the Arctic that has the potential to bind up to 3.97 million tonnes of carbon dioxide-rich particles annually from the Kara and Barents Seas and store them in the deep waters of the Arctic for thousands of years.
According to a recent study by experts from AWI, this carbon conveyor belt transports as much carbon dioxide as Iceland produces in a year using regional ocean currents and the biological carbon pump. One of the most important carbon sinks on Earth is the biological carbon pump. If the carbon is eventually deposited in deep-sea sediments, the technique has the potential to trap it for millions of years. The only thing that can release it at that point is volcanic activity.
Oceanographer at AWID Dr. Andreas Rogge was the study’s primary author and said, “Based on our data, we calculated that by this water-mass transit, more than 2,000 metric tonnes of carbon flow into the Arctic deep sea every day, equivalent to 8,500 metric tonnes of atmospheric CO2.
The research was published in the journal Nature Geoscience under the title Carbon dioxide sink in the Arctic Ocean through cross-shelf transit of dense Barents Sea water.
According to the press release, the Arctic Ocean receives less sunlight as a result of sea ice cover or the Polar Night, which lowers available nutrients and biological productivity. Thus, compared to those in other bodies of water, the phytoplankton, or microalgae, in the upper layers of the water don’t have as much energy at their disposal.
As a result, the discovery of significant quantities of carbon particles preserved in plant remnants in the Nansen Basin of the Central Arctic in August and September 2018 as part of the ARCTIC2018 voyage of the Russian research vessel Akademik Tryoshnikov was unexpected.
The bottom water from the Barents Sea, the lowest layer of ocean water, was discovered to have significant amounts of particulate carbon in the ocean up to a depth of 1.24 miles. When winter sea ice forms, sinks, and then flows from the shallow coastal shelf waters down the slope of the continent into the Arctic Basin, the bottom water is created. From the shelf of the Kara and Barents Seas, the carbon-rich water travels 621 miles into the Arctic Basin.
The Barents Sea removes around 30% more atmospheric carbon than previously believed thanks to this recently discovered carbon delivery artery. The scientists’ calculations revealed that the outflow is seasonal because phytoplankton in the Arctic coastal seas can only absorb carbon dioxide during the summer.
Understanding the transformation and transport mechanisms involved in the carbon cycle is essential for creating global carbon budgets and global warming estimations.
When ocean surface single-celled algae die, they take up carbon from the atmosphere and descend to the bottom of the ocean. In the Arctic, it can take many millennia for the ocean’s currents to carry this bound-up carbon back to the surface.
Additionally, the biological carbon pump provides food for animals living in the deep water, such as sea stars, worms, and sponges. The amount of carbon that is currently absorbed by the nearby deep marine ecosystem is unclear.
As a result of ongoing global warming, less ice and bottom water are generated. Additionally, the phytoplankton has access to more light and nutrients, increasing the amount of CO2 that can be bound. Therefore, it is currently hard to forecast how this carbon sink will develop, and it is urgently necessary to conduct more research in order to identify any potential tipping points, Rogge stated in the press release.