2153942

Bering Strait 2022-2026: Quantifying Status and Change in Pacific-to-Arctic Physical/Biogeochemical Oceanic Fluxes, a Central Part of the Arctic Observing Network

The ~50m deep, 85km wide Bering Strait is the only connection between the Pacific and Arctic Oceans. The generally northward flow through the strait is a key source of oceanic heat, freshwater, and nutrients for the Arctic, influencing the upper ~200m of roughly half of the Arctic Ocean. This provides both a stratified upper ocean layer, which protects sea-ice from deeper and warmer Atlantic origin waters, and a major source of nutrients which fuel Arctic ecosystems.

Oceanic heat carried northward through the strait acts as a trigger for western Arctic sea-ice melt and is the best predictor of sea-ice retreat date in the Chukchi Sea, the highly productive, shallow sea immediately north of the strait. The freshness of the flow may influence ocean circulation as far away as the Atlantic Ocean. To understand and quantify how the climate and ecosystems of the Arctic Ocean and the Alaskan Arctic seas are changing, and how those changes relate to the rest of the globe, observations are needed to quantify the changing properties of the flow through the Bering Strait.

Year-round oceanographic measurements in the strait (from moorings, i.e., instruments moored to the sea-floor) started in 1990 and show the flow is increasing in strength and temperature, and freshening dramatically in winter. These changes are believed to have significant effects on the Arctic and beyond. Additionally, satellite studies, which are indicating large increases at the base of the Arctic food chain, suggest an increased nutrient flux from the Pacific Ocean through the strait. However, to date, no year-round or interannual measurements of nutrient flow through the Bering Strait exist to test this idea.

Since moorings are still the only viable way of measuring seasonal and interannual change in the Bering Strait, this project supports: four years of moorings, measuring physical properties such as flow, temperature, salinity, sea-ice; biogeochemical properties including nutrient content and measures of biological activity; and accompanying analysis and outreach efforts. The latter include making data products and results available to science, public, and industry communities as well as bringing Bering Strait and Arctic science to the general public, university students, and schools, including Bering Strait communities and public and Hispanic/Latino-dominated schools in Seattle, WA.

From September 2022 to September 2026, three year-round moorings will be deployed in the US waters of the Bering Strait region, supported by annual ship-based servicing, and accompanying hydrographic surveys in the Bering Strait and southern Chukchi Sea. Hourly mooring measurements will be used to compute water properties, and fluxes of heat, freshwater, and nitrate into the Arctic. These in situ measurements will be combined with satellite data, numerical weather prediction model data, and verified Arctic model results to investigate causes of change in the throughflow, and to understand and quantify transformations in the Chukchi Sea, thus giving a better estimation of the forcings of the Bering Strait throughflow directly on the Arctic Ocean.

The project aims to obtain the Bering Strait's first year-round measurements of nitrate, the key limiting nutrient of the region, and, by extending the longest in situ physical instrument record from the Arctic Ocean, give a multidecadal measure of change in this key Arctic gateway.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the foundation's intellectual merit and broader impacts review criteria.

University Of Washington

THE GOAL OF THIS FUNDING OPPORTUNITY, "ARCTIC RESEARCH OPPORTUNITIES", IS IDENTIFIED IN THE LINK: HTTPS://WWW.NSF.GOV/PUBLICATIONS/PUB_SUMM.JSP?ODS_KEY=NSF21526

47.078 - Polar Programs

Office of Polar Programs (OPP) [NSF]

Seattle, Washington 98105-6698 United States

Single Zip Code

Arctic Research Opportunities (21-526)

Amendment Since initial award the total obligations have increased 257% from $846,714 to $3,024,625.