• Login
    About WHOAS
    View Item 
    •   WHOAS Home
    • Woods Hole Oceanographic Institution
    • Academic Programs
    • WHOI Theses
    • View Item
    •   WHOAS Home
    • Woods Hole Oceanographic Institution
    • Academic Programs
    • WHOI Theses
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of WHOASCommunities & CollectionsBy Issue DateAuthorsTitlesKeywordsThis CollectionBy Issue DateAuthorsTitlesKeywords

    My Account

    LoginRegister

    Statistics

    View Usage Statistics

    Development and application of the mollusc Arctica islandica as a paleoceanographic tool for the North Atlantic ocean

    Thumbnail
    View/Open
    Weidman_Thesis (41.12Mb)
    Date
    1995-09
    Author
    Weidman, Christopher R.  Concept link
    Metadata
    Show full item record
    Citable URI
    https://hdl.handle.net/1912/5634
    Location
    41°N-70°N
    Northern North Atlantic Ocean
    DOI
    10.1575/1912/5634
    Keyword
     Clams; Paleoclimatology; Ocean quahog 
    Abstract
    Until now there has been no tool comparable to corals for reconstructing long term high-resolution geochemical time-series for the colder, higher-latitude oceans. In this thesis, the long-lived (+100 years) boreal mollusc (Bivalvia) Arctica islandica is shown to be practical for this purpose in the northern North Atlantic Ocean. The evidence, compiled here, demonstrates that the carbonate shell of this species faithfully records the ambient dissolved inorganic carbon's (DIC) radiocarbon (Δ14C) concentration and accurately reflects the ambient temperature in its stable oxygen isotope (δ180) composition. However, the stable carbon isotope (δ13C) composition of the A. islandica shell likely is not a good recorder of ambient DIC δl3C, and likely responds to physiological controls. Four Δ14C time histories are reconstructed from the annual bands of A. islandica shells for the higher-latitudes of the northern North Atlantic Ocean (from 41°N to 70°N). These ocean records show significant spatial and temporal differences in the evolution of the radiocarbon signal between the subpolar and subtropical regions and between eastern and western regions of the northern North Atlantic, which are attributed to regional differences in mixed-layer depth and the presence of deepwater sources. A 109-year interannual record of bottom temperatures for a location near the former Nantucket Lightship position has been reconstructed for the period 1875-1983 from the overlapped stable oxygen isotope composition of four A. islandica shells. This record's annual temperature anomalies (variation from the running ten-year mean) show significant positive correlation with regional bottom, sea surface and air temperature anomalies. However, the shell-derived bottom temperature record describes a century-long cooling (~1°C) in contrast to a century-long warming of regional sea surface temperatures of equal magnitude, indicating a long term divergence between surface and bottom conditions. It is suggested that this contrast may be owed to a reduction in vertical mixing and increased seasonal stratification of shelf waters. This thesis fulfills the prophesy laid out nearly two decades ago by Thompson and Jones [1977] that Arctica islandica could someday be used to reconstruct past ocean history as "the tree of the North Atlantic".
    Description
    Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Woods Hole Oceanographic Institution and the Massachusetts Institute of Technology September 1995
    Collections
    • Geology and Geophysics (G&G)
    • WHOI Theses
    Suggested Citation
    Thesis: Weidman, Christopher R., "Development and application of the mollusc Arctica islandica as a paleoceanographic tool for the North Atlantic ocean", 1995-09, DOI:10.1575/1912/5634, https://hdl.handle.net/1912/5634
     

    Related items

    Showing items related by title, author, creator and subject.

    • Thumbnail

      Understanding the ocean carbon and sulfur cycles in the context of a variable ocean : a study of anthropogenic carbon storage and dimethylsulfide production in the Atlantic Ocean 

      Levine, Naomi M. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2010-02)
      Anthropogenic activity is rapidly changing the global climate through the emission of carbon dioxide. Ocean carbon and sulfur cycles have the potential to impact global climate directly and through feedback loops. Numerical ...
    • Thumbnail

      Near-inertial and thermal upper ocean response to atmospheric forcing in the North Atlantic Ocean 

      Silverthorne, Katherine E. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2010-06)
      Observational and modeling techniques are employed to investigate the thermal and inertial upper ocean response to wind and buoyancy forcing in the North Atlantic Ocean. First, the seasonal kinetic energy variability of ...
    • Thumbnail

      Scale closure in upper ocean optical properties : from single particles to ocean color 

      Green, Rebecca E. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2002-06)
      Predictions of chlorophyll concentration from satellite ocean color are an indicator of phytoplankton primary productivity, with implications for foodweb structure, fisheries, and the global carbon cycle. Current models ...
    All Items in WHOAS are protected by original copyright, with all rights reserved, unless otherwise indicated. WHOAS also supports the use of the Creative Commons licenses for original content.
    A service of the MBLWHOI Library | About WHOAS
    Contact Us | Send Feedback | Privacy Policy
    Core Trust Logo