<html><head><meta http-equiv="Content-Type" content="text/html charset=windows-1252"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">Use aave when your data is on a lat/lon grid, use amean when your data are on an abstract or non-earth-based grid. The amean function assumes all gridpoints have equal areas and get equal weights. The aave funciton applies a weighting based on the sine of the latitude. If you are looking at data on a curvilinear grid, then you are probably interpolating it to a regular lat/lon grid using PDEF, in which case you should use aave(). <div>—Jennifer<br><div><div><br><div><div>On Aug 7, 2015, at 3:29 PM, LI Qi <<a href="mailto:liqi123sh@qq.com">liqi123sh@qq.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div><div>Dear grads community,</div><div><br></div><div>Forgive what is probably a stupid question, but I do not really know the difference between the two.</div><div>I check the docu, and it says:</div><div>aave area average with latitude weighting</div><div>amean area means are not weighted by latitude. Means are weighted by grid interval to account for non-linear grid spacing.</div><div><br></div><div>My question is:</div><div>[1] when to use aave and when amean? why?</div><div>[2] if I have data A on a regular lon/lat grid, and data B on a curvilinear grid, both at regional scale, which function should I use? and what about at global scale?</div><div><br></div><div>Thanks a lot!</div><div>Qi</div></div>_______________________________________________<br>gradsusr mailing list<br><a href="mailto:gradsusr@gradsusr.org">gradsusr@gradsusr.org</a><br>http://gradsusr.org/mailman/listinfo/gradsusr<br></blockquote></div><br><div apple-content-edited="true">
<span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px;"><span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; -webkit-text-decorations-in-effect: none; text-indent: 0px; -webkit-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div>--</div><div>Jennifer M. Adams<br>Center for Ocean-Land-Atmosphere Studies (COLA)<br>111 Research Hall, Mail Stop 2B3<br>George Mason University<br>4400 University Drive<br>Fairfax, VA 22030 <br><br></div><div><br class="khtml-block-placeholder"></div><br class="Apple-interchange-newline"></span></span><br class="Apple-interchange-newline">
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