<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;">Dear all<br>Hi,<br>How can I calculate zonal -mean zonal wind anomaly(propagation for polar vortex) at 500hpa for northern hemisphere in Grads?<br>Best Regards<br>kashki<br><br>Abdolreza&nbsp;Kashki <br>
Ph.D. Student of Climatology<br>
Department of Physical Geography<br>
Faculty of Planing &amp; Geography Science&nbsp;<br>
University of Isfahan&nbsp; <br>
Isfahan, Iran<br>
Postcode:81746-73441<br>
Tel:+98(311)7933119<br>
Fax:+98(311)7932257<br>
Cell:+989151731453</td></tr></table>