<div dir="ltr"><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">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">george.vandenberghe@noaa.gov</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="HOEnZb"><div class="h5">On 02/07/2018 12:47 PM, Prashanth Bhalachandran wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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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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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