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Under a National Science Foundation grant to promote science education in secondary schools, Gail Grimes of Lake Stevens High School in Washington joined APL-UW's Rebecca Woodgate on the Chukchi Sea research cruise. Gail, the lucky teacher selected to participate in this outreach experience, functioned as a member of the research team aboard the icebreaker USCGC Polar Star. She filed daily reports of cruise activities and what it's really like to live and work on a research ice breaker.
Before and after the cruise, Grimes and Woodgate visited three schools in Barrow, Alaska. They taught lessons on arctic oceanography and marine biology.
The science team led by Woodgate embarked on an arctic expedition to determine the influence of the Arctic Ocean's most complex topographic feature on arctic water circulation. Subsurface currents in the Arctic Ocean distribute waters, nutrients, and tracers from the Atlantic and Pacific oceans around and into deep arctic basins. The counterclockwise boundary current that circumnavigates the Arctic Ocean is steered along undersea ridges. The most complex topographic obstacle the current faces is the Mendeleev Ridge/Chukchi Borderland complex about 600 miles north of the Pacific Ocean's entrance to the Arctic Ocean at Bering Strait.
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In a 2000-mile journey that took about 5 weeks, science teams aboard the Polar Star zigzagged around and across the topographic junction of the borderland measuring temperature, salinity, dissolved oxygen, nutrients, chlorofluorocarbons, and other trace elements from the sea surface to the floor—as deep as 2.5 miles in places. Additionally, three strings of moored recording instruments were deployed at the beginning of the expedition and retrieved one month later. They took hourly readings of temperature, salinity, and water velocity. This suite of measurements allows scientists to identify the boundary current's pathways, and quantify the Atlantic, Pacific, and river water influences in the region.
The movement of waters in the Arctic Ocean has implications for both arctic and global climate because of its relationship to sea ice and the surface heat balance the ice cover provides. The colder, fresher Pacific water surface layer insulates the sea ice from the warmer, saltier Atlantic water that brings heat to the deep Arctic Ocean. The interaction and pathways of these waters determine how much heat can escape upward to melt sea ice. Further, the pathways taken at the crossroads can determine the time it takes for water to circumnavigate and exit the Arctic Ocean, and hence communicate with the world ocean at lower latitudes.
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