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<DIV>Dear all</DIV>
<DIV>Hi</DIV>
<DIV>How can I calculate perimeter of a special contour for example 5400 in 500 hpa to km in Grads?</DIV>
<DIV>How can I calculate centriod (lat and lon) of a special contour(for example 5400) in 500 hpa ?</DIV>
<DIV>sincerely yours<BR>Abdolreza Kashki <BR><BR>Abdolreza Kashki <BR>Ph.D. Student of Climatology<BR>Department of Physical Geography<BR>Faculty of Planing & Geography Science <BR>University of Isfahan <BR>Isfahan, Iran<BR>Postcode:81746-73441<BR>Tel:+98(311)7933119<BR>Fax:+98(311)7932257<BR>Cell:+989151731453</DIV></td></tr></table>