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As far as I can recall, few studies of long-distance migratory species state what projections are used. Is there any published study of the effect of projections on analyses of animal movement?</div>
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<div>M. J. McGrady </div>
<div>Am Rosenhugel 59</div>
<div>A-3500 Krems</div>
<div>Austria</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> Qgis-user <qgis-user-bounces@lists.osgeo.org> on behalf of Hernán De Angelis <variablestarlight@gmail.com><br>
<b>Sent:</b> Thursday, October 22, 2020 6:57 AM<br>
<b>To:</b> qgis-user@lists.osgeo.org <qgis-user@lists.osgeo.org><br>
<b>Subject:</b> Re: [Qgis-user] Projections</font>
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<p style="margin-top: 0px; margin-bottom: 0px;">Mike</p>
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<p style="margin-top: 0px; margin-bottom: 0px;">For measuring the kind of distances you are mentioning I would suggest using ellipsoidal (geodetic) distances rather than projected distances. This is because projected distances can become very inaccurate over
large regions (depending on the particular projection of course).<br>
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<p style="margin-top: 0px; margin-bottom: 0px;">If measuring areas is important consider an equal area projection, like Albers for example, not a conformal one like Lambert.</p>
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<p style="margin-top: 0px; margin-bottom: 0px;">Hope this helps.<br>
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<p style="margin-top: 0px; margin-bottom: 0px;">/H.<br>
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<div class="x_moz-cite-prefix">On 2020-10-22 07:43, MIKE MCGRADY wrote:<br>
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I have data on tracked migratory birds, and want accurate measures of distance travelled during migration and areas of summering and wintering ranges. These birds are summering in central Asia (mostly Kazakhstan and southern Russia), and wintering in Arabia.
Any advice on which projection to use? My guess is Lambert conformal conic. I'd really like to avoid using different projections for different phases of the birds' annual cycle, unless absolutely necessary. </div>
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<div>M. J. McGrady </div>
<div>Am Rosenhugel 59</div>
<div>A-3500 Krems</div>
<div>Austria</div>
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