The organic carbon flux to Arctic margin sediments: redox tracers stable isotopes and biomarkers as proxies for change

• Main Authors: Gobeil, Charles, Wright, Cynthia, Rancourt, Lise, Marie-Ève Randlett, Goni, Miguel, Fournier, Pauline, Robie W. Macdonald, Jobidon, Sandra, Zou Zou Kuzyk
• Format: Dataset
• Language: English
• Published: Canadian Cryospheric Information Network 2012
• Subjects: 137-Cs; 210-Pb; Baffin Bay; Canadian Arctic Archipelago; Carbon fluxes; Davis Strait; Organic carbon; Organic matter; Sediment cores; Stable isotope tracers; International Polar Year-The organic carbon flux to Arctic margin sediments redox tracers, stable isotopes and biomarkers as proxies for change; Arctic; Arctic Ocean; Canada; Pacific; Barrow Canyon; Arctic Archipelago; Baffin; Canadian Archipelago; Chukchi; Climate change; International Polar Year; Mackenzie Shelf; Sea ice
• Online Access: https://dx.doi.org/10.5443/11418; https://www.polardata.ca/pdcsearch/?doi_id=11418

To date, sediment cores have been successfully collected, while aboard the CCGS Sir Wilfrid Laurier in July 2007, and the CCGS Louis S. St. Laurent in July, 2009. The suite of cores spans the continental shelf and slope at depths varying from 60 to 2000 m from the Bering and Chukchi Seas, to Barrow Canyon, to the Mackenzie Shelf, Davis Strait, Baffin Bay and Canadian Archipelago. The analysis of the samples is now completed and we are now working on the interpretation of results. There is a lot that can be learned from the sediment cores. So far, the results show strong differences in the sediments and organic carbon between different regions of the Arctic. Areas that are very productive with algae and the marine food web, like the North Water Polynya in northern Baffin Bay, have very different organic carbon cycles from areas near river mouths that are strongly influenced by the land. We plan to characterize each region in detail and also compare the regions to produce an overall picture of the organic carbon cycle in the Canadian Arctic continental margin. We will also identify if the organic carbon cycle has been affected by the climate-related changes already underway.of climate change. : Purpose: This project focuses on coastal areas and continental shelves of the Arctic Ocean. Its purpose is to determine the sources, pathways, and fate of the organic carbon deposited in the sediments. Organic carbon plays an important role for sustaining local food webs. It is also important in the global carbon cycle. Marine algae and land plants represent the main sources of the sedimentary organic carbon in coastal zones. However, climate change and associated changes in sea ice cover, river runoff, and ocean circulation are currently impacting how much and what type of organic carbon is supplied to the coastal areas of the Arctic Ocean and also what happens to the material (transport, degradation) within the marine environment. Therefore, the goal of this study is to learn more about the distributions, amounts and specific sources of organic carbon in sediments right now, at the beginning of the changes, so we can be in a better position to face future impacts of climate change. : Summary: Carbon is essential to the chemistry of life and the continental shelves of the oceans are critical sites for carbon cycling. Given the amount of continental shelf associated with the Arctic Ocean, understanding carbon in the Arctic Ocean is paramount to understanding physical and biogeochemical processes involving carbon. To investigate how unique features of the Arctic, such as sea ice and climate, affect carbon cycling, this project collected sediment cores along the margins of Canada's Arctic Ocean to compare to cores being collected in Canada¿s Atlantic and Pacific Oceans. Through sediment coring, a 40,000-year history of carbon in Canada¿s three oceans is being gained.