Abstracts

Modeling Large Scale Primary Production and Related Dimethyl Sulfide Production Within Arctic Sea Ice

Clara Deal¹, Meibing Jin², Scott Elliott³, Elizabeth Hunke⁴, Mathew Maltrud⁵, Nicole Jeffery^6
1International Arctic Research Center, University of Alaska Fairbanks, PO Box 757340, 930 Koyukuk Drive, Fairbanks, AK, 99775, USA, Phone 907 474-1875, Fax 907 474-2643, deal@iarc.uaf.edu
²International Arctic Research Center, Fairbanks, AK, USA
³Los Alamos National Laboratory, Los Alamos, NM, USA
⁴Los Alamos National Laboratory, Los Alamos, NM, USA
⁵Los Alamos National Laboratory, Los Alamos, NM, USA
⁶Los Alamos National Laboratory, Los Alamos, NM, USA

The consequences of diminishing arctic sea ice on marine ecosystems extend well beyond the loss of habitat. In addition to being the base of the ice-associated food web, algae living within sea ice are an important food source for pelagic and benthic herbivores and regulators of biogeochemical cycles. With reduction in sea ice extent and thickness comes changing spatial and temporal patterns of ice algal production and its release into the water column as well as altered dimethyl sulfide (DMS) emissions. An initial step towards including these processes in regional and global predictive models is to realistically model sea ice primary production on large scales. Proceeding along this path, we have coupled an ice ecosystem model to a global dynamic sea ice model to investigate large scale variability in ice algal abundance, primary production, and DMS production within arctic sea ice. The component models are the International Arctic Research Center (IARC) ice ecosystem model and the Los Alamos National Laboratory sea ice model (CICE). The coupled model results help fill in the large spatial and temporal gaps between sparse field observations of ice algal standing stock and productivity. The Bering Sea and Arctic Ocean basins were found to be the most productive regions (in terms of sea ice primary production) for different reasons. In the model, ice growth rate is key to controlling the availability of nutrients to sea ice algae and thus ice algal growth. The model study brings us closer to including the role of sea ice algae in carbon (C) flux, biogeochemical cycling and biosphere-climate feedbacks within global climate models.

Abstract Categories: 1.1 Advances in Understanding Arctic System Components