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Data were collected on Cruise identifier (ID) OS1901_L1 between August 1, 2019 and August 24, 2019 from either the surface uncontaminated seawater supply of research vessel (R/V) Ocean Starr or from Niskin-style water sample bottles attached to a conductivity-temperature-depth package maintained by the National Oceanic and Atmospheric Administration (NOAA) Pacific Marine Environmental Laboratory. Data were collected periodically over the cruise track which departed from Dutch Harbor, Alaska (AK) and sampled waters of the Bering and Chukchi Sea, ending in Nome, AK. This was a part of the Arctic Integrated Ecosystem Survey (Arctic IES) program. The objective of Arctic IES is to understand how reductions in Arctic sea ice and the associated changes in the physical environment influence the flow of energy through the ecosystems of the Chukchi and Beaufort seas. Two research expeditions in the Beaufort and Chukchi seas during late summer and early fall 2017 and 2019 were designed to address this objective. This survey takes measurements of the: 1) physical environment (temperature, salinity, nutrients); 2) seasonal composition, distribution and production of phytoplankton (plants); 3) distribution and standing stocks of zooplankton (bird, whale, and fish food); 4) assemblages, distributions, abundances, size, diet, and fitness of larval, early juvenile, and adult fishes; and 5) distribution and relative abundances of seabirds and marine mammals. The measurements here contribute to characterizing both the chemical environment and the rate of net biological oxygen production. 

Data were collected between August 1, 2019 and August 24, 2019 using a commercially available gas tension device (GTD) made by Pro-Oceanus (miniTDGP) connected to the surface uncontaminated seawater supply (which had a nominal intake depth of 3.5 meters) of Ocean Starr on leg 1 of Cruise identifier (ID) OS1901. Data were collected near-continuously over the cruise track which departed from Dutch Harbor, Alaska (AK) and sampled waters of the Bering and Chukchi Sea, ending in Nome, AK. The objective of Arctic IES is to understand how reductions in Arctic sea ice and the associated changes in the physical environment influence the flow of energy through the ecosystems of the Chukchi and Beaufort seas. Two research expeditions in the Beaufort and Chukchi seas during late summer and early fall 2017 and 2019 were designed to address this objective. This survey takes measurements of the: 1) physical environment (temperature, salinity, nutrients); 2) seasonal composition, distribution and production of phytoplankton (plants); 3) distribution and standing stocks of zooplankton (bird, whale, and fish food); 4) assemblages, distributions, abundances, size, diet, and fitness of larval, early juvenile, and adult fishes; and 5) distribution and relative abundances of seabirds and marine mammals. The measurements here contribute to characterizing both the chemical environment and the rate of net biological oxygen production. 

Data were collected between August 1, 2019 and August 24, 2019 using an equilibrated inlet mass spectrometer (EIMS, Cassar et al. 2009) connected to the surface uncontaminated seawater supply (which had a nominal intake depth of 3.5 meters) of Ocean Starr on leg 1 of Cruise identifier (ID) OS1901. Data were collected near-continuously over the cruise track which departed from Dutch Harbor, Alaska (AK) and sampled waters of the Bering and Chukchi Sea, ending in Nome, AK. This was a part of the Arctic Integrated Ecosystem Survey (Arctic IES) program. The objective of Arctic IES is to understand how reductions in Arctic sea ice and the associated changes in the physical environment influence the flow of energy through the ecosystems of the Chukchi and Beaufort seas. Two research expeditions in the Beaufort and Chukchi seas during late summer and early fall 2017 and 2019 were designed to address this objective. This survey takes measurements of the: 1) physical environment (temperature, salinity, nutrients); 2) seasonal composition, distribution and production of phytoplankton (plants); 3) distribution and standing stocks of zooplankton (bird, whale, and fish food); 4) assemblages, distributions, abundances, size, diet, and fitness of larval, early juvenile, and adult fishes; and 5) distribution and relative abundances of seabirds and marine mammals. The measurements here contribute to characterizing both the chemical environment and the rate of net biological oxygen production. 

Abstract From late‐summer 2013 to late‐summer 2014, a total of 20 moorings were maintained on the eastern Chukchi Sea shelf as part of five independent field programs. This provided the opportunity to analyze an extensive set of timeseries to obtain a broad view of the mean and seasonally varying hydrography and circulation over the course of the year. Year‐long mean bottom temperatures reflected the presence of the strong coastal circulation pathway, while mean bottom salinities were influenced by polynya/lead activity along the coast. The timing of the warm water appearance in spring/summer is linked to advection along the various flow pathways. The timing of the cold water appearance in fall/winter was not reflective of advection nor related to the time of freeze‐up. Near the latitude of Barrow Canyon, the cold water was accompanied by freshening. A one‐dimensional mixed‐layer model demonstrates that wind mixing, due to synoptic storms, overturns the water column resulting in the appearance of the cold water. The loitering pack ice in the region, together with warm southerly winds, melted ice and provided an intermittent source of fresh water that was mixed to depth according to the model. Farther north, the ambient stratification prohibits wind‐driven overturning, hence the cold water arrives from the south. The circulation during the warm and cold months of the year is different in both strength and pattern. Our study highlights the multitude of factors involved in setting the seasonal cycle of hydrography and circulation on the Chukchi shelf.