Oceans and biogeochemistry
The deep oceans serve as vast chemical storehouses, holding 50 times as much carbon as the atmosphere and billions of tons of nitrogen and phosphorus. As these deep waters mix and upwell to the well-lit surface waters, they fuel biological productivity comparable in magnitude to all terrestrial plants. Ongoing work with the Oceans and Climate Group involves understanding the interaction of ocean circulation and biological and chemical cycling within the ocean. Areas of particular interest include
- How can knowledge of chemical cycling improve our understanding of the large-scale ocean circulation? Tracers such as radiocarbon, a radioactive isotope of carbon produced in the stratosphere and by nuclear bombs, provide information about how long water in the ocean interior has been away from the surface, and where this water might return to the surface.
- What is the role of the large-scale oceanic circulation in controlling the atmospheric carbon dioxide? Our work shows that ocean biology sequesters significant amounts of carbon in the deep ocean, but that the amount sequestered depends on ocean circulation as well as biology.
- How do ecosystems change as climate changes? In cooperation with the Climate and Ecosystems Group we are developing Earth System Models that can be used to look at how the distribution of marine plants, the nitrogen and phosphorus that they consume, and the oxygen that they produce all change in response to natural and anthropogenic climate change.
- Do ecosystems directly affect climate? Recent work within the group suggests that by changing the distribution of solar heating within the ocean, marine life can directly affect climate.
Anand Gnanadesikan (Ocean color, tracers and biogeochemical cycles)
Robbie Toggweiler (Radiocarbon, biological cycling and carbon cycle)
Whit Anderson (Climate Change, Variability and Predictability Group, ocean color)
John Dunne (Climate and Ecosystems Group, global carbon cycle, global ecosystem modeling)
Jorge Sarmiento (AOS Program, Global carbon cycle, tracers and biogeochemical cycles)
Eric Galbraith (AOS Program, tracers and biogeochemical cycles)
Links
Click here to learn more about the Southern Ocean Biogeochemical Divide.
Click here to learn about the impact of ocean color.
Click here to return to the Oceans and Climate Group home page.
