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<p class="MsoNormal" style="line-height:6pt;margin:0in;font-size:11pt;font-family:"Aptos",sans-serif"><span style="font-family:"Times New Roman",serif">Hi, Phellow Phriammers,<span> </span>Nick, here. <span></span></span></p>
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<p class="MsoNormal" style="line-height:6pt;margin:0in;font-size:11pt;font-family:"Aptos",sans-serif"><span style="font-family:"Times New Roman",serif">I have been lost in the
weather.<span> </span>This publication,<span></span></span></p>
<p class="MsoNormal" style="margin:0in;font-size:11pt;font-family:"Aptos",sans-serif"><span style="font-family:"Times New Roman",serif"><br></span></p><p class="MsoNormal" style="margin:0in;font-size:11pt;font-family:"Aptos",sans-serif"><span style="font-family:"Times New Roman",serif"><a href="https://acrobat.adobe.com/id/urn:aaid:sc:us:d481610b-e5d5-4a03-879c-6db6ec1d5e4a" style="color:rgb(70,120,134);text-decoration:underline" target="_blank">https://acrobat.adobe.com/id/urn:aaid:sc:us:d481610b-e5d5-4a03-879c-6db6ec1d5e4a</a><br></span></p><p class="MsoNormal" style="margin:0in;font-size:11pt;font-family:"Aptos",sans-serif"><span style="font-family:"Times New Roman",serif"><span><br></span></span></p>
<p class="MsoNormal" style="margin:0in;font-size:11pt;font-family:"Aptos",sans-serif"><span style="font-family:"Times New Roman",serif">with its
glorious eye-candy, is an example of what seems to be a new perspective in
meteorology, the DT-PV perspective.<span> </span>PV
refers to a parameter, potential vorticity, which seems to be a measure of how
liable the atmosphere is to churn; DT refers to the DYNAMIC
tropopause.<span> </span>The tropopause is the
transition zone between the stratosphere and our own layer, the troposphere, through
which gas exchange is limited because the lapse rate of the troposphere<span> </span>-- its decline in temperature with fall of
pressure -- is reversed in the stratosphere.<span>
</span>In the Bad Old Days, we were taught that the tropopause was like a
ceiling, tilted upward from the poles to the tropics.<span> </span>Now we have begun to think of it as more like
a tent fly, still tilted up equator-ward, but loose and floppy and buffeted up
and down by the jetstreams’ winds. These floppings up and down have the power
to destabilize the lower atmosphere and lead to bad weather, if conditions there are
ripe. <span></span></span></p>
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<p class="MsoNormal" style="margin:0in;font-size:11pt;font-family:"Aptos",sans-serif"><span style="font-family:"Times New Roman",serif">This is
not one of my usual cries for help.<span> </span>I have
some good tutors. However, I would love to hear from others whom this paper
interests. In particular I am struggling with the notion of potential vorticity, whose formula seems to take many odd forms.<span></span></span></p>
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<p class="MsoNormal" style="margin:0in;font-size:11pt;font-family:"Aptos",sans-serif"><span style="font-family:"Times New Roman",serif">Best, <span></span></span></p>
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<p class="MsoNormal" style="margin:0in;font-size:11pt;font-family:"Aptos",sans-serif"><span style="font-family:"Times New Roman",serif">Nick<span></span></span></p>
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<p class="MsoNormal" style="margin:0in;font-size:11pt;font-family:"Aptos",sans-serif"><span><span style="font-family:"Times New Roman",serif">Nicholas S. Thompson<span></span></span></span></p>
<p class="MsoNormal" style="margin:0in;font-size:11pt;font-family:"Aptos",sans-serif"><span><span style="font-family:"Times New Roman",serif">Emeritus Professor of Psychology
and Ethology<span></span></span></span></p>
<p class="MsoNormal" style="margin:0in;font-size:11pt;font-family:"Aptos",sans-serif"><span><span style="font-family:"Times New Roman",serif">Clark University,<span></span></span></span></p>
<p class="MsoNormal" style="margin:0in;font-size:11pt;font-family:"Aptos",sans-serif"><span><span style="font-family:"Times New Roman",serif"><a href="mailto:nthompson@clarku.edu" target="_blank">nthompson@clarku.edu</a> <span></span></span></span></p>
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