Climate change induced spectacular increase of the land-ocean inputs in the Arctic Ocean

Science Highlights

9 January 2018

Measurements of radium-228 (228Ra) in the framework of the 2015 U.S. GEOTRACES Arctic Transect (GN01), revealed that the surface water content of this tracer has almost doubled over the last decade, specifically in the Transpolar Drift near the North Pole.

Radium isotopes are excellent tracers of land-ocean inputs. A mass balance model for 228Ra allowed Kipp and co-workers (2018, see reference below) to suggest that this increase is due to an intensification of shelf-derived material inputs to the central basin. These coastal changes, in turn, could also be delivering more nutrients, carbon, and other chemicals into the Arctic Ocean and lead to dramatic impacts on Arctic food webs and animal populations.

Figure: Diminishing sea ice near the Arctic coast leaves more open water near the coast for winds to create waves. The increased wave action reaches down and stirs up sediments on shallow continental shelves, releasing radium and other chemicals that are carried up to the surface and swept away into the open ocean by currents such as the Transpolar Drift. Artwork: Natalie Renier, Woods Hole Oceanographic Institution. Please click here to view the figure larger.

Reference:

Kipp, L. E., Charette, M. A., Moore, W. S., Henderson, P. B., & Rigor, I. G. (2018). Increased fluxes of shelf-derived materials to the central Arctic Ocean. Science Advances, 4(1), eaao1302. DOI: http://doi.org/10.1126/sciadv.aao1302

Latest highlights

Major controls on the fate of dissolved manganese in the northeastern Indian Ocean

Malla and Singh investigated the key factors controlling dissolved manganese in the northeastern Indian Ocean.

An original approach to assess the particulate trace metal concentrations in seawater

Sohrin and co-workers propose defining particulate trace metal as the difference between total dissolvable and dissolved metals after a long storage of filtered and unfiltered acidified seawater.

Constraining aerosol deposition over the global ocean by the cosmogenic beryllium-7

He and co-workers propose a global estimate of aerosol deposition onto the ocean using the cosmogenic radionuclide beryllium-7.

Oceanic lead concentrations and isotopes mapped using explainable machine learning

Using three machine learning models, Olivelli and her colleagues generated global climatologies of lead concentrations and isotopes…

Rechercher