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Discrete samples were collected on research cruise ID NRS2022 (-01T, -01S, -02S) between July 12, 2022 and September 5, 2022, and analyzed for oxygen/argon ratios and triple oxygen isotopes. Samples were collected intermittently from the underway seawater supply throughout the cruise, which departed from Homer, Alaska (AK) and sampled waters of the Bering, Chukchi, and Beaufort Seas, ending in Nome, AK. Samples were also collected at various depths from a selection of conductivity, temperature, and depth (CTD) casts during the second leg of the cruise (NRS2022_02S). The measurements here contribute to characterizing both the chemical environment and the rates of net and gross biological oxygen production in the Pacific-influenced Arctic. 

Data were collected between July 13, 2022 and September 5, 2022 using an equilibrated inlet mass spectrometer (EIMS, Cassar et al., 2009) connected to the surface seawater supply of Norseman II on Cruise ID NRS2022 (01T, 01S, 02S). Data were collected near-continuously over the cruise track which departed from Homer, Alaska (AK) and sampled waters of the Bering, Chukchi and Beaufort seas, ending in Nome, AK. The measurements here contribute to characterizing both the chemical environment and the rate of net biological oxygen production. 

Abstract The production and export of organic matter to deep‐sea sediments is a key driver in modulating glacial‐interglacial carbon cycles. Yet, it remains unsettled whether productivity has increased or decreased over glacial‐interglacial transitions, in part because productivity proxies may be complicated by sediment re‐deposition and diagenetic alterations. Here, we explore using non‐spinose foraminifera Ba/Ca ratios as a proxy for surface ocean productivity. We analyze foraminifera Ba/Ca ratios since the Last Glacial Maximum in cores that span a productivity gradient along the equatorial Pacific. Ba/Ca is low and invariable in the spinose speciesTrilobatus sacculifer. In contrast, Ba/Ca is higher and more variable in the non‐spinose speciesNeogloboquadrina dutertreiandPulleniatina obliquiloculata. Ba/Ca enrichment in non‐spinose species is hypothesized to be linked to the degradation of organic matter within the species' particulate microhabitat and reflects surface ocean particulate organic matter productivity at the time of shell calcification (Fehrenbacher et al., 2018,https://doi.org/10.1016/j.gca.2018.03.008). Ba/Ca in core‐top and sediment trap derived non‐spinose foraminifera correlate with organic matter productivity. We reconstruct an increase in non‐spinose species Ba/Ca during the deglacial in the western and eastern equatorial Pacific and suggest this may be linked to an increase in productivity, as observed in several other regional records. The 16–17 ka BP peak in non‐spinose foraminifera Ba/Ca is evident in specimens obtained from a deep ocean core and from regions that experience sediment focusing, suggesting the Ba/Ca proxy may be useful even in regions where samples are poorly preserved or complicated by sediment re‐deposition. 

Abstract The Bering Sea is a highly productive subarctic ecosystem with some of the most valuable commercial fisheries in the United States. This seasonally ice‐covered sea has been rapidly changing due to ocean warming with impacts to the ecosystem structure and fisheries. The long‐term effects of these shifts on primary producers, however, are still unknown. Continuous monitoring of primary productivity in the Bering Sea is critical, yet observations that capture the ephemeral nature of plankton are challenging to sustain. To address this gap, high temporal resolution primary productivity rates were quantified at a mooring site (M2) in the southeastern Bering Sea in 2021. From a suite of sensors at M2 (fluorescence, dissolved oxygen, temperature, and total dissolved gas pressure), we calculated gross primary productivity (GPP), net primary productivity (NPP), and net community productivity (NCP), the latter based on net biological oxygen saturation using dissolved oxygen/nitrogen (O₂/N₂) ratios. These estimates elucidate weekly patterns from the spring bloom through fall, when the water column becomes well‐mixed. In 2021, we observed average productivity during the spring bloom, yet wind patterns and mixing dynamics during the spring contributed to low productivity during summer and fall. The 2021 productivity metrics (GPP, NPP, and NCP) were compared across the growing season and contrasted with seasonal productivity estimates at M2 in previous years with consideration given to variability of ice conditions (warm/cold years) and wind stress. 

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 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 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.