Conductivity, temperature, and depth (CTD) data collected on the research vessel Sikuliaq, Northeast Chukchi and Western Beaufort Seas, 2016 (NCEI Accession 0278971)

The Conductivity, temperature, and depth ((CTD) )data archived here were collected during a 2016 research cruise on the Research Vessel (R/V) Sikuliaq (SKQ201612S). The cruise departed Nome September 3, 2016 and returned Sept 25, 2016. CTD stations were occupied throughout the NE Chukchi and Western Beaufort. We occupied some Distributed Biological Observatory (DBO) stations as part of this work, including DBO4, DBO5, and DBO6.

Satellite measurements have documented significant reductions in sea ice cover, thickness, and duration throughout the Arctic Ocean in recent decades. Because of the complex interactions and feedbacks among physical, biogeochemical and ecological processes in the Arctic, there is significant uncertainty regarding how these changes in sea ice will impact the marine biological pump, which fuels the rich bottom communities on Arctic ocean shelves and is key to the regional carbon cycle. While responses of the biological pump to increased light availability in spring are currently being pursued, a considerable gap in knowledge exists regarding biological processes in the late summer and early fall. Recent studies indicate a several-decade trend of intensifying wind forcing over the Alaskan margin along the Chukchi and Beaufort Seas in the late, ice-free season (September-November). These events could lead to mixing of nutrients into surface waters, fueling increased biological production and sequestering additional carbon into shelf bottom waters prior to the winter ice advance. However, the lack of direct, concurrent observations of primary and net community productivity rates, and nutrient and carbon distributions during this poorly-sampled time of year hinders efforts to assess the ecosystem implications of such changes. The goal of this project was to address the question of increasing biological production in the late season through intensive field sampling in two successive years.