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    <div class="moz-cite-prefix">Where the concept is relevant  (with an
      enormous number of caveats, yes) is to answer the fundamental
      question, will TC interaction with baroclinicity, induce
      transition to a growing or stable baroclinic system (often
      observed) or will the TC perturbation just damp out (also often
      observed) with a theoretically expected but hard to actually point
      out, increase in baroclinic available potential energy for some
      future perturbation to extract.<br>
      <br>
      I am obviously not an expert either (and my M.S is 31 years
      stale)  and I did sleep at home last night, not in a Holiday Inn 
      Express but I think it is a tractable forecast and theoretical
      modeling problem, again with the caveats mentioned below.<br>
      <br>
      Casually plugging this into a program without understanding the
      concepts is worrisome, also agreed.<br>
      <br>
      Thanks everyone for the response!<br>
      <br>
      On 02/09/2018 10:25 AM, Dennis Shea wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:CAOF1d_7smX9kWrASHy7mjCg8LpOqTNViDz2xSb3+EzpdA+LOAg@mail.gmail.com">
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        <div>
          <div>I am not really knowledgeable about Eady Growth Rate
            (EGR) so  I asked a person and got the following response:<br>
            --------<br>
            <div>
              <div>
                <div>Hi Dennis,<br>
                  <br>
                </div>
                Ha!  When I google Eady growth rate, the first thing
                that comes up is your NCL function and the second thing
                that comes up are some class notes that I wrote when I
                taught a course.  Apparently we are the state of
                knowledge on Eady growth rate, which is slightly
                concerning.<br>
                <br>
              </div>
              Erm, for [1] I don't think the Eady model is intended to
              tell you something about tropical cyclone environments. 
              It's really intended to describe the growth of
              mid-latitude eddies.  Since it's formulated on an f-plane,
              I don't think it's really appropriate for use in tropical
              environments.  That being said, the eady growth rate
              really is just a measure of baroclinicity so it might be
              fine to determine what the baroclinicity is in their
              tropical cyclone environments.  <br>
            </div>
            <div><br>
            </div>
            <div>For [2b] I'd say no too.  But I don't think using
              equivalent potential temperature would work either.  I
              think you'd have to include a diabatic heating term in the
              thermodynamic equation that's being solved to account for
              the release of heat associated with the convergence of
              moisture and precipitation that accompanies the growing
              wave.  WIth my expert googling skils, I came across
              this...     <a
                href="https://iri.columbia.edu/%7Etippett/pubs/moist.pdf"
                target="_blank" moz-do-not-send="true">https://iri.columbia.edu/~<wbr>tippett/pubs/moist.pdf</a></div>
            <div><br>
            </div>
            For [2a] I don't really know the answer.  But I'm also not
            sure how you would measure the real world growth rates.  The
            eady model is intended to describe the growth of the normal
            modes and I think you could compare the predictions with a
            normal mode calculation using the real world basic state but
            I'm not sure how you would actually measure the growth rates
            of the real world.  I also think it might give you a
            dimensionless growth rate which tells you what scales
            dominate by growing fastest, but I'm not sure to what extent
            it is something that can be compared with the real world. 
            In short, I don't really know. <br>
            -----------<br>
          </div>
          HTH<br>
        </div>
        D<br>
      </div>
      <div class="gmail_extra"><br>
        <div class="gmail_quote">On Wed, Feb 7, 2018 at 10:56 AM, George
          Vandenberghe <span dir="ltr"><<a
              href="mailto:george.vandenberghe@noaa.gov" target="_blank"
              moz-do-not-send="true">george.vandenberghe@noaa.gov</a>></span>
          wrote:<br>
          <blockquote class="gmail_quote">
            <div class="HOEnZb">
              <div class="h5">On 02/07/2018 12:47 PM, Prashanth
                Bhalachandran wrote:<br>
                <blockquote class="gmail_quote">
                  Hello all,<br>
                  I want to compare the baroclinity of two tropical
                  cyclone environments. What is the best way to do this
                  using NCL?<br>
                  <br>
                  I did some digging and found a function to calculate
                  Eady growth rate in v6.4 . I have never used it thus
                  far, so I want to know what the options are.<br>
                  <br>
                  Thank you,<br>
                  Prashanth<br>
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                </blockquote>
                <br>
              </div>
            </div>
            Okay this is tangential to the topic but VERY INTERESTING in
            its own right.  How well do the observed growth rates<br>
            <br>
            for (presumably large scale because small length scale
            damps) compare with the theoretical Eady growth rates<br>
            <br>
            and (something I should know but don't) do Eady growth rates
            incorporate the effect of moisture on stratification?
            <div class="HOEnZb">
              <div class="h5"><br>
                <br>
                <br>
                <br>
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          </blockquote>
        </div>
        <br>
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    </blockquote>
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