ER">
<PRE>
     <B>Contact:</B>   Isaac Held
     <B>Reviewers:</B>

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<A NAME="OVERVIEW">
<HR>
<H4>OVERVIEW</H4>
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<PRE>

     Adds the tendencies due to vertical diffusion to the tendencies
     of model prognostic variables  
     

</PRE>
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<A NAME="DESCRIPTION">
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