Convincing evidence now confirms that polar regions are changing rapidly in response to human activities. Changes in sea ice extent and thickness will have profound implications for productivity, food webs and carbon fluxes at high latitudes, since sea ice biota are a significant source of biogenic matter for the ecosystem. While sea ice is often thought to be a barrier to gas exchange between the ocean and the atmosphere, it more likely functions as a source or sink for climate-active gases such as carbon dioxide and ozone-depleting organohalogens, due in part to activities of microbes embedded in the sea ice matrix. This project brings together experienced US and Swedish investigators to examine the controls by sea-ice biota on the production and degradation of key climate-active gases in the Pacific sector of the Southern Ocean. We hypothesize that 1) the physical properties of the sea-ice environment will determine the community structure and activities of the sea ice biota; 2) the productivity, biomass, physiological state and species composition of ice algae will determine the production of specific classes of organic carbon, including organohalogens; 3) heterotrophic co-metabolism within the ice will break down these compounds to some extent, depending on the microbial community structure and productivity, and 4) the sea ice to atmosphere fluxes of CO2 and organohalogens will be inversely related. This project will build close scientific collaborations between US and Swedish researchers and also train young scientists, including members of underrepresented groups. Dissemination of results will include the scientific literature, and public outreach venues including interactions with a PolarTrec teacher.

Agency
National Science Foundation (NSF)
Institute
Division of Polar Programs (PLR)
Type
Standard Grant (Standard)
Application #
0836112
Program Officer
Roberta L. Marinelli
Project Start
Project End
Budget Start
2008-09-01
Budget End
2010-08-31
Support Year
Fiscal Year
2008
Total Cost
$125,733
Indirect Cost
Name
College of William & Mary Virginia Institute of Marine Science
Department
Type
DUNS #
City
Gloucester Point
State
VA
Country
United States
Zip Code
23062