Analyzing Arctic water flow and connections to biological drivers
The overall goal of the Distributed Biological Observatory – Northern Chukchi Integrated Study (DBO-NCIS) is to document and understand ongoing changes to the Pacific-Arctic ecosystem in light of changing physical drivers. The project will continue the analysis of physical data collected on the DBO-NCIS cruises to date (2017-2021), in conjunction with ancillary and historical data, while collaborating with the interdisciplinary team of scientists involved in the program. This includes a study of the changing halocline of the Beaufort Gyre, the formation and spreading of newly formed winter water on the Beaufort shelf, and the Pacific Water flow branches on the Chukchi shelf. These and other efforts have continued to advance our understanding of the water mass composition, transformation, and progression of flow from the Bering Strait to the Arctic Basin, and how this in turn impacts Arctic ecosystems.
Project Mission & Goals
The DBO-NCIS project is divided into two different studies. Read more about their objectives below.
The first study addresses the evolution of the Beaufort Gyre over the past two decades. Results imply that continued thinning of the cold halocline layer could disrupt the present stable state of the gyre, allowing for a significant freshwater release. This in turn could freshen the subpolar North Atlantic, impacting the Atlantic Meridional Overturning Circulation.
The second study investigates aspects of newly ventilated winter water (NVWW), which is a cold, salty, nutrient-rich water mass that is critical for supporting the ecosystem of the western Arctic Ocean. The analysis includes using time series from a previous mooring array deployed across the shelf and slope in the western Beaufort Sea near 150°W from 2008-9. Results show that the salty NVWW can be fluxed off the shelf due to the convergence of the westward-flowing current on the shelf and the eastward-flowing outflow from Barrow Canyon.
In addition to these studies, we are compiling and updating an historical database of shipboard acoustic Doppler current profiler (SADCP) data on the Chukchi shelf. The climatology is called ChukSA (Chukchi Sea shipboard ADCP), and to date it includes data from 57 cruises over the time period 2002-2022. We will continue to expand this database using data from both domestic and foreign vessels, including the R/V Marai (JAMSTEC), the R/V Xue Long (PRIC), the USCGC Healy, and the CCGS Laurier (DFO). We are also including ADCP data from Saildrones. Such a composite data set is extremely valuable for quantifying the basic circulation of the Chukchi shelf, its response to wind forcing, and the fluxes of volume, heat, salt, and nutrients across the shelf.