The Distributed Biological Observatory (DBO)-Northern Chukchi Integrated Study (NCIS): Hydrography, Sediment, and Macrofaunal Population Dynamics

Jacqueline M. Grebmeier (lead PI) and Lee W. Cooper (Co-PI), University of Maryland Center for Environmental Science Chesapeake Biological Laboratory

ABSTRACT

Understanding the impacts of reduced seasonal sea ice and a warming water column on benthic processes are essential to track and forecast ecosystem response in the Pacific Arctic region. Within the geographical area of the southern Chukchi Sea northward to the slope of the Chukchi Sea, we propose collections of several key water column parameters (oxygen stable isotopes, phytoplankton species composition), sediment parameters (carbon and nitrogen content, grain size, stable isotope C and N content, sediment core radiositopes and metabolism measurements) and benthic macrofaunal composition and biomass to determine hydrographic and sediment characteristics that influence macroinfaunal communities and ecosystem function. This sampling is planned for: (1) the time-series Distributed Biological Observatory (DBO) transect lines from the southern Chukchi Sea to the northern part of the Chukchi Sea and Barrow Canyon (DBO3-5), and (2) focused sediment process studies in the northern Chukchi Sea and slope regions to track ecosystem response to sea ice retreat and seawater warming. The proposed approach, to be undertaken in concert with other investigators, will evaluate key processes influencing the Pacific Arctic ecosystem. These interdisciplinary investigations will address variability and forcing functions in the diverse water masses and benthic habitat types that are now subject to significantly longer sea-ice free periods.

The proposed work builds on prior efforts conducted during the DBO program that is supported by multiple US federal agencies and the Circumpolar Biodiversity Monitoring Program (CBMP), which is an international Arctic Council program. We will collaborate within the Pacific Arctic Group (PAG, a consortium of coordinated Pacific Arctic research activities by China, USA, Russia, Canada, Korea, and Japan) to provide for efficient international collaborations in the Arctic. These coordination and sampling efforts place the proposed work within the following foci areas of NOAA’s Arctic Research Program, specifically: (1) the Arctic Ocean-Ecosystem benthic fluxes interactions network as part of the PAG international coordination, including the previous Russian-American program, RUSALCA, (2) the DBO program, and (3) the Arctic Council’s CBMP-Marine program. The proposed observations support NOAA’s Next Generation Strategic Plan (NGSP) that includes objectives to understand the marine Arctic ecosystem, support observing systems, and facilitate climate monitoring.