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  1. Story 450223212

    As Google is discontinuing the email subscription function of the Feedburner service (https://developers.google.com/search/blog/2021/04/changes-to-feedburner) C-CAN posts can be delivered via email by registering to subscribe to the following feed: https://follow.it/c-can-california-current-acidification-network?action=followPub

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  2. Story 444454469

    In response to the April announcement; https://developers.google.com/search/blog/2021/04/changes-to-feedburner C-CAN has been researching alternative services such as MailChimp, as well as WordPress plugins that would serve as the best solution to replace the current Feedburner service which will be discontinuing it’s email subscription function.

    Posts will continue to reside under NEWS in the menu bar, but having it delivered to your door via an email subscription was the one  feature of Feedburner that benefited readers the most. This RSS Redirect Test is being made to determine whether a redirect solution can be made seamlessly without asking readers to resubscribe via another service.

    Unfortunately, as announced by Google, a solution or a change will have to be made in order to continue to deliver C-CAN posts to subscribers via Feedburner.

    There are a number of solutions, but most all require readers to resubscribe. This RSS Redirect Test will determine whether that will be the direction that will need to be followed.

  3. Story 444353405

    Assessing the vulnerability of marine invertebrates to ocean acidification (OA) requires an understanding of critical thresholds at which developmental, physiological, and behavioral traits are affected. To identify relevant thresholds for echinoderms, we undertook a three-step data synthesis, focused on California Current Ecosystem (CCE) species. First, literature characterizing echinoderm responses to OA was compiled, creating a dataset comprised of >12,000 datapoints from 41 studies. Analysis of this data set demonstrated responses related to physiology, behavior, growth and development, and increased mortality in the larval and adult stages to low pH exposure. Second, statistical analyses were conducted on selected pathways to identify OA thresholds specific to duration, taxa, and depth-related life stage. Exposure to reduced pH led to impaired responses across a range of physiology, behavior, growth and development, and mortality endpoints for both larval and adult stages. Third, through discussions and synthesis, the expert panel identified a set of eight duration-dependent, life stage, and habitat-dependent pH thresholds and assigned each a confidence score based on quantity and agreement of evidence. The thresholds for these effects ranged within pH from 7.20 to 7.74 and duration from 7 to 30 days, all of which were characterized with either medium or low confidence. These thresholds yielded a risk range from early warning to lethal impacts, providing the foundation for consistent interpretation of OA monitoring data or numerical ocean model simulations to support climate change marine vulnerability assessments and evaluation of ocean management strategies. As a demonstration, two echinoderm thresholds were applied to simulations of a CCE numerical model to visualize the effects of current state of pH conditions on potential habitat.

    Bednaršek N., Calosi P., Feely R. A., Ambrose R., Byrne M., Chan K. Y. K., Dupont S., Padilla-Gamiño J. L., Spicer J. I., Kessouri F., Roethler M., Sutula M. & Weisberg S. B., 2021. Synthesis of thresholds of ocean acidification impacts on echinoderms. Frontiers in Marine Science 8: 602601. doi: 10.3389/fmars.2021.602601. Article.


    Original post: https://news-oceanacidification-icc.org/2021/05/20/synthesis-of-thresholds-of-ocean-acidification-impacts-on-echinoderms/

  4. Story 444353404

    Faycal Kessouri, James C. McWilliams, Daniele Bianchi, Martha Sutula, Lionel Renault, Curtis Deutsch, Richard A. Feely, Karen McLaughlin, Minna Ho, Evan M. Howard, Nina Bednaršek, Pierre Damien, Jeroen Molemaker, and Stephen B. Weisberg


    1. aDepartment of Biogeochemistry, Southern California Coastal Water Research Project, Costa Mesa, CA 92626;

    2. bDepartment of Atmospheric and Oceanic Sciences, University of California Los Angeles, Los Angeles, CA 90095;

    3. cLaboratoire d’Études en Géophysique et Océanographie Spatiale, Institut de Recherche et de Developpement, CNRS, Université Paul Sabatier, Toulouse 31400, France;

    4. dSchool of Oceanography, University of Washington, Seattle, WA 98195;

    5. ePacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, Seattle, WA 98115;

    6. fNational Institute of Biology, Marine Biological Station Piran, 6330 Piran, Slovenia

    Significance

    We conduct a modeling study of the effects of enhanced coastal nutrient export from human activities on the carbon, nitrogen, and oxygen cycles of the Southern California Bight, in the context of emerging global climate change. The modeling approach used is innovative in the breadth of its scope, and simulations are generally consistent with local measurements. The human effects on the regional ecosystem from coastal nitrogen inputs of 23 million people are substantial, leading to significant increases in the photosynthesis and biomass of phytoplankton and increased oxygen loss and acidification of the water column. These changes are likely to compress habitat for a variety of marine organisms, with cascading ecological effects and implications for marine resources and water-quality management.

    Abstract

    Global change is leading to warming, acidification, and oxygen loss in the ocean. In the Southern California Bight, an eastern boundary upwelling system, these stressors are exacerbated by the localized discharge of anthropogenically enhanced nutrients from a coastal population of 23 million people. Here, we use simulations with a high-resolution, physical–biogeochemical model to quantify the link between terrestrial and atmospheric nutrients, organic matter, and carbon inputs and biogeochemical change in the coastal waters of the Southern California Bight. The model is forced by large-scale climatic drivers and a reconstruction of local inputs via rivers, wastewater outfalls, and atmospheric deposition; it captures the fine scales of ocean circulation along the shelf; and it is validated against a large collection of physical and biogeochemical observations. Local land-based and atmospheric inputs, enhanced by anthropogenic sources, drive a 79% increase in phytoplankton biomass, a 23% increase in primary production, and a nearly 44% increase in subsurface respiration rates along the coast in summer, reshaping the biogeochemistry of the Southern California Bight. Seasonal reductions in subsurface oxygen, pH, and aragonite saturation state, by up to 50 mmol m−3, 0.09, and 0.47, respectively, rival or exceed the global open-ocean oxygen loss and acidification since the preindustrial period. The biological effects of these changes on local fisheries, proliferation of harmful algal blooms, water clarity, and submerged aquatic vegetation have yet to be fully explored.


    Original post: https://www.pnas.org/content/118/21/e2018856118

  5. Story 444353403

    Samantha A. Siedlecki1, Darren Pilcher2,5, Evan M. Howard3, Curtis Deutsch3, Parker MacCready3, Emily L. Norton2, Hartmut Frenzel3, Jan Newton4, Richard A. Feely5, Simone R. Alin5, and Terrie Klinger6

    • 1Department of Marine Sciences, University of Connecticut, Groton, CT 06340, USA
    • 2Joint Institute for the Study of the Atmosphere and Ocean, University of Washington, Seattle, WA, 98105, USA
    • 3School of Oceanography, University of Washington, Seattle, WA 98195, USA
    • 4Applied Physics Laboratory, Washington Ocean Acidification Center, University of Washington, Seattle, WA 98105, USA
    • 5NOAA Pacific Marine Environmental Laboratory (PMEL), Seattle, WA 98115, USA
    • 6School of Marine Environment and Affairs, Washington Ocean Acidification Center, University of Washington, Seattle, WA 98105, USA

    Correspondence: Samantha A. Siedlecki (samantha.siedlecki@uconn.edu)

    Received: 17 Jul 2020 – Discussion started: 05 Aug 2020 – Revised: 04 Mar 2021 – Accepted: 13 Mar 2021 – Published: 11 May 2021

     

    Abstract

    Global projections for ocean conditions in 2100 predict that the North Pacific will experience some of the largest changes. Coastal processes that drive variability in the region can alter these projected changes but are poorly resolved by global coarse-resolution models. We quantify the degree to which local processes modify biogeochemical changes in the eastern boundary California Current System (CCS) using multi-model regionally downscaled climate projections of multiple climate-associated stressors (temperature, O2, pH, saturation state (Ω), and CO2). The downscaled projections predict changes consistent with the directional change from the global projections for the same emissions scenario. However, the magnitude and spatial variability of projected changes are modified in the downscaled projections for carbon variables. Future changes in pCO2 and surface Ω are amplified, while changes in pH and upper 200 m Ω are dampened relative to the projected change in global models. Surface carbon variable changes are highly correlated to changes in dissolved inorganic carbon (DIC), pCO2 changes over the upper 200 m are correlated to total alkalinity (TA), and changes at the bottom are correlated to DIC and nutrient changes. The correlations in these latter two regions suggest that future changes in carbon variables are influenced by nutrient cycling, changes in benthic–pelagic coupling, and TA resolved by the downscaled projections. Within the CCS, differences in global and downscaled climate stressors are spatially variable, and the northern CCS experiences the most intense modification. These projected changes are consistent with the continued reduction in source water oxygen; increase in source water nutrients; and, combined with solubility-driven changes, altered future upwelled source waters in the CCS. The results presented here suggest that projections that resolve coastal processes are necessary for adequate representation of the magnitude of projected change in carbon stressors in the CCS.