The oceans play a significant role in absorbing greenhouse gases, like carbon dioxide, and heat from the atmosphere. This absorption can help mitigate the early effects of human-emissions of carbon dioxide.
The Atlantic Meridional Overturning Circulation acts as a conveyor belt of ocean water from Florida to Greenland. Along the journey north, water near the surface absorbs greenhouse gases, which sink down as the water cools near Greenland. In this way, the ocean effectively buries the gases deep below the surface.
The world’s oceans are like brakes slowing down the full effects of greenhouse gas warming of the atmosphere. Over the last ten years, one-fourth of human-emissions of carbon dioxide as well as 90 percent of additional warming due to the greenhouse effect have been absorbed by the oceans. Acting like a massive sponge, the oceans pull from the atmosphere heat, carbon dioxide and other gases, such as chlorofluorocarbons, oxygen and nitrogen and store them in their depths for decades to centuries and millennia.
New NASA research is one of the first studies to estimate how much and how quickly the ocean absorbs atmospheric gases and contrast it with the efficiency of heat absorption. Using two computer models that simulate the ocean, NASA and MIT scientists found that gases are more easily absorbed over time than heat energy. In addition, they found that in scenarios where the ocean current slows down due to the addition of heat, the ocean absorbs less of both atmospheric gases and heat, though its ability to absorb heat is more greatly reduced. The results were published in Geophysical Research Letters, a journal of the American Geophysical Union.