Sleeping Giant in Our Oceans

Red medusa found just off the bottom of the deep sea in Alaska. 

Credit: Hidden Ocean 2005/NOAA

A previously overlooked factor — the position of continents — helps fill Earth’s oceans with life-supporting oxygen. Continental movement could ultimately have the opposite effect, killing the majority of deep ocean creatures.

“Continental drift seems so slow, like nothing drastic could come from it, but when the ocean is primed, even a seemingly tiny event could trigger the widespread death of marine life,” said Andy Ridgwell, University of California, Riverside geologist. Ridgwell is co-author of a new study on forces affecting oceanic oxygen.

As the water at the ocean’s surface approaches the north or south pole, it becomes colder and denser and then sinks. When the water sinks, it transports oxygen pulled from Earth’s atmosphere down to the ocean floor.

Eventually, a return flow brings nutrients released from sunken organic matter back to the ocean’s surface, where it fuels the growth of plankton. Today’s oceans feature an incredible diversity of fish and other animals that are supported by both the uninterrupted supply of oxygen to lower depths and organic matter produced at the surface.

New research has found that this circulation of oxygen and nutrients can end quite suddenly. Using complex computer models, the scientists investigated whether the locations of continental plates affect how the ocean moves oxygen around. They were surprised to find that it does.

This finding led by researchers based at UC Riverside is detailed in the journal Nature. It was published today (August 17, 2022).  READ MORE...