Stabeno
Phyllis J.
Stabeno
Phyllis J.
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ArticleMean and seasonal circulation of the eastern Chukchi Sea from moored timeseries in 2013-2014(American Geophysical Union, 2021-04-30) Tian, Fei ; Pickart, Robert S. ; Lin, Peigen ; Pacini, Astrid ; Moore, G. W. K. ; Stabeno, Phyllis J. ; Weingartner, Thomas J. ; Itoh, Motoyo ; Kikuchi, Takashi ; Dobbins, Elizabeth ; Bell, Shaun ; Woodgate, Rebecca ; Danielson, Seth L. ; Wang, ZhaominFrom 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.
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PreprintAn introduction and overview of the Bering Sea Project : volume IV( 2016-08-18) Van Pelt, Thomas I. ; Napp, Jeffrey M. ; Ashjian, Carin J. ; Harvey, H. Rodger ; Lomas, Michael W. ; Sigler, Michael F. ; Stabeno, Phyllis J.The seasonal rhythm of sea-ice advance and retreat in the eastern Bering Sea (EBS) moves ice hundreds of kilometers across the broad continental shelf and exerts a powerful influence on the ecology of these waters. In winter, the combination of latitude, geology, winds, and ocean currents produces ice cover extending far into the southern Bering Sea. In the spring and summer, retreating ice, longer daylight hours, and nutrient-rich ocean water result in exceptionally high marine production, vital to both sea life and people. The intense burst of spring production, together with more episodic summer and early fall production, provides the energy that powers the complex food web and ultimately sustains nearly half of the US annual commercial fish landings, as well as providing food and cultural value to thousands of Bering Sea coastal and island residents.
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ArticleMonitoring Alaskan Arctic shelf ecosystems through collaborative observation networks(Oceanography Society, 2022-04-28) Danielson, Seth L. ; Grebmeier, Jacqueline M. ; Iken, Katrin ; Berchok, Catherine L. ; Britt, Lyle ; Dunton, Kenneth ; Eisner, Lisa B. ; Farley, Edward V. ; Fujiwara, Amane ; Hauser, Donna D.W. ; Itoh, Motoyo ; Kikuchi, Takashi ; Kotwicki, Stan ; Kuletz, Kathy J. ; Mordy, Calvin W. ; Nishino, Shigeto ; Peralta-Ferriz, Cecilia ; Pickart, Robert S. ; Stabeno, Phyllis J. ; Stafford, Kathleen M. ; Whiting, Alex V. ; Woodgate, RebeccaOngoing scientific programs that monitor marine environmental and ecological systems and changes comprise an informal but collaborative, information-rich, and spatially extensive network for the Alaskan Arctic continental shelves. Such programs reflect contributions and priorities of regional, national, and international funding agencies, as well as private donors and communities. These science programs are operated by a variety of local, regional, state, and national agencies, and academic, Tribal, for-profit, and nongovernmental nonprofit entities. Efforts include research ship and autonomous vehicle surveys, year-long mooring deployments, and observations from coastal communities. Inter-program coordination allows cost-effective leveraging of field logistics and collected data into value-added information that fosters new insights unattainable by any single program operating alone. Coordination occurs at many levels, from discussions at marine mammal co-management meetings and interagency meetings to scientific symposia and data workshops. Together, the efforts represented by this collection of loosely linked long-term monitoring programs enable a biologically focused scientific foundation for understanding ecosystem responses to warming water temperatures and declining Arctic sea ice. Here, we introduce a variety of currently active monitoring efforts in the Alaskan Arctic marine realm that exemplify the above attributes.
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ArticleParalytic shellfish toxins in Alaskan Arctic food webs during the anomalously warm ocean conditions of 2019 and estimated toxin doses to Pacific walruses and bowhead whales(Elsevier, 2022-03-03) Lefebvre, Kathi A. ; Fachon, Evangeline ; Bowers, Emily K. ; Kimmel, David G. ; Snyder, Jonathan A. ; Stimmelmayr, Raphaela ; Grebmeier, Jacqueline M. ; Kibler, Steve ; Hardison, D. Ransom ; Anderson, Donald M. ; Kulis, David M. ; Murphy, James M. ; Gann, Jeanette C. ; Cooper, Daniel W. ; Eisner, Lisa B. ; Duffy-Anderson, Janet T. ; Sheffield, Gay ; Pickart, Robert S. ; Mounsey, Anna ; Willis, Maryjean L. ; Stabeno, Phyllis J. ; Siddon, ElizabethClimate change-related ocean warming and reduction in Arctic sea ice extent, duration and thickness increase the risk of toxic blooms of the dinoflagellate Alexandrium catenella in the Alaskan Arctic. This algal species produces neurotoxins that impact marine wildlife health and cause the human illness known as paralytic shellfish poisoning (PSP). This study reports Paralytic Shellfish Toxin (PST) concentrations quantified in Arctic food web samples that include phytoplankton, zooplankton, benthic clams, benthic worms, and pelagic fish collected throughout summer 2019 during anomalously warm ocean conditions. PSTs (saxitoxin equivalents, STX eq.) were detected in all trophic levels with concentrations above the seafood safety regulatory limit (80 μg STX eq. 100 g−1) in benthic clams collected offshore on the continental shelf in the Beaufort, Chukchi, and Bering Seas. Most notably, toxic benthic clams (Macoma calcarea) were found north of Saint Lawrence Island where Pacific walruses (Odobenus rosmarus) are known to forage for a variety of benthic species, including Macoma. Additionally, fecal samples collected from 13 walruses harvested for subsistence purposes near Saint Lawrence Island during March to May 2019, all contained detectable levels of STX, with fecal samples from two animals (78 and 72 μg STX eq. 100 g−1) near the seafood safety regulatory limit. In contrast, 64% of fecal samples from zooplankton-feeding bowhead whales (n = 9) harvested between March and September 2019 in coastal waters of the Beaufort Sea near Utqiaġvik (formerly Barrow) and Kaktovik were toxin-positive, and those levels were significantly lower than in walruses (max bowhead 8.5 μg STX eq. 100 g−1). This was consistent with the lower concentrations of PSTs found in regional zooplankton prey. Maximum ecologically-relevant daily toxin doses to walruses feeding on clams and bowhead whales feeding on zooplankton were estimated to be 21.5 and 0.7 μg STX eq. kg body weight−1 day−1, respectively, suggesting that walruses had higher PST exposures than bowhead whales. Average and maximum STX doses in walruses were in the range reported previously to cause illness and/or death in humans and humpback whales, while bowhead whale doses were well below those levels. These findings raise concerns regarding potential increases in PST/STX exposure risks and health impacts to Arctic marine mammals as ocean warming and sea ice reduction continue.
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ArticleResults of the first Arctic Heat Open Science Experiment(American Meteorological Society, 2018-04-19) Wood, Kevin R. ; Jayne, Steven R. ; Mordy, Calvin W. ; Bond, Nicholas A. ; Overland, James E. ; Ladd, Carol ; Stabeno, Phyllis J. ; Ekholm, Alexander K. ; Robbins, Pelle E. ; Schreck, Mary-Beth ; Heim, Rebecca ; Intrieri, JanetSeasonally ice-covered marginal seas are among the most difficult regions in the Arctic to study. Physical constraints imposed by the variable presence of sea ice in all stages of growth and melt make the upper water column and air–sea ice interface especially challenging to observe. At the same time, the flow of solar energy through Alaska’s marginal seas is one of the most important regulators of their weather and climate, sea ice cover, and ecosystems. The deficiency of observing systems in these areas hampers forecast services in the region and is a major contributor to large uncertainties in modeling and related climate projections. The Arctic Heat Open Science Experiment strives to fill this observation gap with an array of innovative autonomous floats and other near-real-time weather and ocean sensing systems. These capabilities allow continuous monitoring of the seasonally evolving state of the Chukchi Sea, including its heat content. Data collected by this project are distributed in near–real time on project websites and on the Global Telecommunications System (GTS), with the objectives of (i) providing timely delivery of observations for use in weather and sea ice forecasts, for model, and for reanalysis applications and (ii) supporting ongoing research activities across disciplines. This research supports improved forecast services that protect and enhance the safety and economic viability of maritime and coastal community activities in Alaska. Data are free and open to all (see www.pmel.noaa.gov/arctic-heat/).
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ArticleThe Pacific water flow branches in the eastern Chukchi Sea(Elsevier, 2023-11-10) Pickart, Robert S. ; Lin, Peigen ; Bahr, Frank B. ; McRaven, Leah T. ; Huang, Jie ; Pacini, Astrid ; Arrigo, Kevin Robert ; Ashjian, Carin J. ; Berchok, Catherine L. ; Baumgartner, Mark F. ; Cho, Kyoungho ; Cooper, Lee W. ; Danielson, Seth L. ; Dasher, Doug H. ; Fuiwara, Amane ; Gann, Jeanette C. ; Grebmeier, Jacqueline M. ; He, Jiangfeng ; Hirawake, Toru ; Itoh, Motoyo ; Juranek, Laurie ; Kikuchi, Takashi ; Moore, G. W. Kent ; Napp, Jeffrey M. ; John Nelson, R. ; Nishino, Shigeto ; Statscewich, Hank ; Stabeno, Phyllis J. ; Stafford, Kathleen M. ; Ueno, Hiromichi ; Vagle, Svein ; Weingartner, Thomas J. ; Williams, Bill ; Zimmermann, Sarah L.The flow of Pacific-origin water across the Chukchi Sea shelf impacts the regional ecosystem in profound ways, yet the two current branches on the eastern shelf that carry the water from Bering Strait to Barrow Canyon – the Alaskan Coastal Current (ACC) and Central Channel (CC) Branch – have not been clearly distinguished or quantified. In this study we use an extensive collection of repeat hydrographic sections occupied at three locations on the Chukchi shelf, together with data from a climatology of shipboard velocity data, to accomplish this. The data were collected predominantly between 2010 and 2020 during the warm months of the year as part of the Distributed Biological Observatory and Arctic Observing Network. The mean sections show that mass is balanced for both currents at the three locations: Bering Strait, Point Hope, and Barrow Canyon. The overall mean ACC transport is 0.34 ± 0.04 Sv, and that of the CC Branch is 0.86 ± 0.11 Sv. The dominant hydrographic variability at Bering Strait is seasonal, but this becomes less evident to the north. At Barrow Canyon, the dominant hydrographic signal is associated with year-to-year variations in sea-ice melt. Farther south there is pronounced mesoscale variability: an empirical orthogonal function analysis at Bering Strait and Point Hope reveals a distinct ACC mode and CC Branch mode in hydrography and baroclinic transport, where the former is wind-driven. Finally, the northward evolution in properties of the two currents is investigated. The poleward increase in salinity of the ACC can be explained by lateral mixing alone, but solar heating together with wind mixing play a large role in the temperature evolution. This same atmospheric forcing also impacts the northward evolution of the CC Branch.