• 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

    Linear normal mode analysis of baroclinic instability in a meridional channel

    Thumbnail
    View/Open
    Walker_thesis.pdf (1.732Mb)
    Date
    2001-03
    Author
    Walker, Alison  Concept link
    Metadata
    Show full item record
    Citable URI
    https://hdl.handle.net/1912/3046
    DOI
    10.1575/1912/3046
    Keyword
    Baroclinicity
    Abstract
    Numerical solutions of the unstable, growing modes are found for the two-layer inviscid quasigeostrophic equations in a meridional channel. A steady mean flow in the N-S direction is imposed in the upper layer, and it is assumed that changes in planetary vorticity following this mean flow are balanced by the input of vorticity from an imposed wind stress curl. Thus in the two-layer system, the vertical shear, in thermal wind balance, is associated with an interface slope which provides a gradient of potential vorticity (PV) in the x-direction, of equal magnitude and opposite sign in the two layers. In the y-direction the PV gradient has the value of planetary beta, β in both layers. The unstable modes of this system exhibit a boundary-layer structure across the channel. They are intensified in the west. The growth rates of the unstable modes are of the same order as the zonal case, however the range of wavenumber and shear for which instability is possible is larger. Established cutoff criteria for the equal-layer zonal case are not applicable, and no analogous criteria has yet been found. Growing modes are found even for very weakly sheared flows, and this suggests that baroclinic instability may represent a more significant source of mid-ocean eddy energy than previously believed.
    Description
    Submitted in partial fulfillment of the requirements for the degree of Master of Science at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution March 2001
    Collections
    • WHOI Theses
    • Physical Oceanography (PO)
    Suggested Citation
    Thesis: Walker, Alison, "Linear normal mode analysis of baroclinic instability in a meridional channel", 2001-03, DOI:10.1575/1912/3046, https://hdl.handle.net/1912/3046
     

    Related items

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

    • Thumbnail

      Baroclinic instability of a meridionally varying basic state 

      Meacham, Stephen P. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1984-06)
      Several problems are addressed herein. They are loosely connected by the theme of resonant triad interactions. The main topic is the finite amplitude evolution of weakly unstable, linear eigenmodes in a meridionally ...
    • Thumbnail

      Generation of mid-ocean eddies : the local baroclinic instability hypothesis 

      Arbic, Brian K. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2000-08)
      The plausibility of local baroclinic instability as a generation mechanism for midocean mesoscale eddies is examined with a two-layer, quasi-geostrophic (QG) model forced by an imposed, horizontally homogeneous, vertically ...
    • Thumbnail

      Instabilities and radiation of thin, baroclinic jets 

      Talley, Lynne D. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1982-06)
      Oceanic fluctuations are dependent on geographical location. Near intense currents, the eddy field is highly energetic and has broad meridional extent. It is likely that the energy arises from instabilities of the intense ...
    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