The Dynamics of Carbon Export to the Deep Arctic Ocean and its Sensitivity to Climate Change
Arctic Research Initiative
2007 Funded Project
The Arctic Ocean is of critical importance for our understanding of the impact and fate of anthropogenically-induced increases in atmospheric CO2 on the oceans and on global climate. It has been predicted that anthropogenically-driven climate change will occur far more rapidly and be amplified in the Arctic, both on the surrounding continents and in the ocean. Two of the most blatant manifestations of this change are a reduction in sea-ice cover and destabilization of permafrost soils. The latter process and attendant shifts in the hydrologic cycle will release vast quantities of reduced carbon stored in these soils and associated nutrients to the marginal seas. Together with longer open-water seasons over larger expanses of the Arctic Ocean, carbon export to the interior basin is likely to increase markedly. However, our knowledge of the operation of the carbon cycle in the Arctic Ocean, the efficacy of the biological pump, and its response to changes in supply of carbon is severely hampered by the paucity of information on fluxes and fate of biogenic and associated materials exported from the upper ocean to the interior basins.In anticipation of dramatic changes to the arctic carbon cycle, we propose a project designed to provide crucial insights into the sources, mode of delivery and fate of carbon in the deep arctic basin. We propose to undertake time-series collection of settling particles in the CanadianBasin and to utilize geochemical tracers and synchronous physical oceanographic measurements to delineate mechanisms that govern carbon export to the deep basin. In this way, we will be in a better position to predict how the Arctic carbon cycle may be modified in the face of the climate changes which have been set in motion.