22
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      Ocean warming since 1982 has expanded the niche of toxic algal blooms in the North Atlantic and North Pacific oceans

      research-article

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Significance

          This study used high-resolution (daily, quarter-degree resolution) sea-surface temperature records to model trends in growth rates and bloom-season duration for two of the most toxic and widespread harmful algal bloom species indigenous to the North Atlantic and North Pacific oceans. Alexandrium fundyense synthesizes saxitoxin and Dinophysis acuminata synthesizes okadaic acid, which cause the human health syndromes paralytic and diarrhetic shellfish poisoning, respectively. The model provided hindcasts of harmful algal bloom (HAB) events that were consistent with in situ observations from long-term monitoring programs during the same time period. This study provides evidence that increasing ocean temperatures have already facilitated the intensification of these, and likely other, HABs and thus contribute to an expanding human health threat.

          Abstract

          Global ocean temperatures are rising, yet the impacts of such changes on harmful algal blooms (HABs) are not fully understood. Here we used high-resolution sea-surface temperature records (1982 to 2016) and temperature-dependent growth rates of two algae that produce potent biotoxins, Alexandrium fundyense and Dinophysis acuminata, to evaluate recent changes in these HABs. For both species, potential mean annual growth rates and duration of bloom seasons significantly increased within many coastal Atlantic regions between 40°N and 60°N, where incidents of these HABs have emerged and expanded in recent decades. Widespread trends were less evident across the North Pacific, although regions were identified across the Salish Sea and along the Alaskan coastline where blooms have recently emerged, and there have been significant increases in the potential growth rates and duration of these HAB events. We conclude that increasing ocean temperature is an important factor facilitating the intensification of these, and likely other, HABs and thus contributes to an expanding human health threat.

          Related collections

          Most cited references50

          • Record: found
          • Abstract: found
          • Article: found

          Ocean acidification: the other CO2 problem.

          Rising atmospheric carbon dioxide (CO2), primarily from human fossil fuel combustion, reduces ocean pH and causes wholesale shifts in seawater carbonate chemistry. The process of ocean acidification is well documented in field data, and the rate will accelerate over this century unless future CO2 emissions are curbed dramatically. Acidification alters seawater chemical speciation and biogeochemical cycles of many elements and compounds. One well-known effect is the lowering of calcium carbonate saturation states, which impacts shell-forming marine organisms from plankton to benthic molluscs, echinoderms, and corals. Many calcifying species exhibit reduced calcification and growth rates in laboratory experiments under high-CO2 conditions. Ocean acidification also causes an increase in carbon fixation rates in some photosynthetic organisms (both calcifying and noncalcifying). The potential for marine organisms to adapt to increasing CO2 and broader implications for ocean ecosystems are not well known; both are high priorities for future research. Although ocean pH has varied in the geological past, paleo-events may be only imperfect analogs to current conditions.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Impact of climate change on marine pelagic phenology and trophic mismatch.

            Phenology, the study of annually recurring life cycle events such as the timing of migrations and flowering, can provide particularly sensitive indicators of climate change. Changes in phenology may be important to ecosystem function because the level of response to climate change may vary across functional groups and multiple trophic levels. The decoupling of phenological relationships will have important ramifications for trophic interactions, altering food-web structures and leading to eventual ecosystem-level changes. Temperate marine environments may be particularly vulnerable to these changes because the recruitment success of higher trophic levels is highly dependent on synchronization with pulsed planktonic production. Using long-term data of 66 plankton taxa during the period from 1958 to 2002, we investigated whether climate warming signals are emergent across all trophic levels and functional groups within an ecological community. Here we show that not only is the marine pelagic community responding to climate changes, but also that the level of response differs throughout the community and the seasonal cycle, leading to a mismatch between trophic levels and functional groups.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Climate-driven trends in contemporary ocean productivity.

              Contributing roughly half of the biosphere's net primary production (NPP), photosynthesis by oceanic phytoplankton is a vital link in the cycling of carbon between living and inorganic stocks. Each day, more than a hundred million tons of carbon in the form of CO2 are fixed into organic material by these ubiquitous, microscopic plants of the upper ocean, and each day a similar amount of organic carbon is transferred into marine ecosystems by sinking and grazing. The distribution of phytoplankton biomass and NPP is defined by the availability of light and nutrients (nitrogen, phosphate, iron). These growth-limiting factors are in turn regulated by physical processes of ocean circulation, mixed-layer dynamics, upwelling, atmospheric dust deposition, and the solar cycle. Satellite measurements of ocean colour provide a means of quantifying ocean productivity on a global scale and linking its variability to environmental factors. Here we describe global ocean NPP changes detected from space over the past decade. The period is dominated by an initial increase in NPP of 1,930 teragrams of carbon a year (Tg C yr(-1)), followed by a prolonged decrease averaging 190 Tg C yr(-1). These trends are driven by changes occurring in the expansive stratified low-latitude oceans and are tightly coupled to coincident climate variability. This link between the physical environment and ocean biology functions through changes in upper-ocean temperature and stratification, which influence the availability of nutrients for phytoplankton growth. The observed reductions in ocean productivity during the recent post-1999 warming period provide insight on how future climate change can alter marine food webs.
                Bookmark

                Author and article information

                Journal
                Proc Natl Acad Sci U S A
                Proc. Natl. Acad. Sci. U.S.A
                pnas
                pnas
                PNAS
                Proceedings of the National Academy of Sciences of the United States of America
                National Academy of Sciences
                0027-8424
                1091-6490
                9 May 2017
                24 April 2017
                : 114
                : 19
                : 4975-4980
                Affiliations
                [1] aSchool of Marine and Atmospheric Sciences, Stony Brook University , Southampton, NY 11968;
                [2] b Eagle Rock Analytics , Sacramento, CA 95820;
                [3] cCenter for Coastal Fisheries and Habitat Research, National Ocean Service, National Oceanic and Atmospheric Administration , Beaufort, NC 28516
                Author notes
                1To whom correspondence should be addressed. Email: christopher.gobler@ 123456stonybrook.edu .

                Edited by David M. Karl, University of Hawaii, Honolulu, HI, and approved March 23, 2017 (received for review November 28, 2016)

                Author contributions: C.J.G. and O.M.D. designed research; O.M.D. and T.K.H.-L. performed research; C.J.G. and O.M.D. contributed new reagents/analytic tools; C.J.G., O.M.D., T.K.H.-L., A.W.G., Y.K., and R.W.L. analyzed data; and C.J.G., O.M.D., T.K.H.-L., A.W.G., Y.K., and R.W.L. wrote the paper.

                Article
                PMC5441705 PMC5441705 5441705 201619575
                10.1073/pnas.1619575114
                5441705
                28439007
                3f91558b-f82c-47cb-a0de-1bda4a16ed4b
                History
                Page count
                Pages: 6
                Funding
                Funded by: Simons Foundation (SF) 100000893
                Award ID: none
                Funded by: DOC | National Oceanic and Atmospheric Administration (NOAA) 100000192
                Award ID: NA11NOS4780027
                Funded by: DOC | National Oceanic and Atmospheric Administration (NOAA) 100000192
                Award ID: NA15NOS4780183
                Categories
                Biological Sciences
                Ecology

                climate change,bloom duration,sea-surface temperature, Dinophysis , Alexandrium

                Comments

                Comment on this article