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If my memory serves me correctly, the U.S. National Geodetic Survey (NGS) computed the Mexican geoid. Dr. Tomas Soler was involved as I recall who is/was the Senior Geodesist at NGS. I think it's public domain.</div>
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<p><font face="Copperplate Gothic Bold">Clifford J. Mugnier, c.p., c.m.s.</font></p>
<p><font face="Copperplate Gothic Bold">Chief of Geodesy</font></p>
<p><font face="Copperplate Gothic Bold">LSU Center for GeoInformatics (ERAD 266)</font></p>
<p><font face="Copperplate Gothic Bold">Dept. of Civil Engineering (P.F. Taylor 3240H)</font></p>
<p><font face="Copperplate Gothic Bold"><b>LOUISIANA STATE UNIVERSITY</b></font></p>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> PROJ <proj-bounces@lists.osgeo.org> on behalf of Javier Jimenez Shaw <j1@jimenezshaw.com><br>
<b>Sent:</b> Monday, July 19, 2021 3:43 AM<br>
<b>To:</b> proj <PROJ@lists.osgeo.org><br>
<b>Subject:</b> [PROJ] About Mexican Geoid</font>
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<div>Hi</div>
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<div>Recently I found that Mexico has a geoid model, used with vcrs NAVD88: GGM10 - Geoide gravimétrico mexicano 2010<br>
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<div><a href="https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fen.www.inegi.org.mx%2Ftemas%2Fgeoide%2F%23Downloads&data=04%7C01%7Ccjmce%40lsu.edu%7C21f6ad5c27544f9d08ac08d94a914bf1%7C2d4dad3f50ae47d983a09ae2b1f466f8%7C0%7C0%7C637622810781009658%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000&sdata=dl22Hz7HsFb81wsjH0RLnIpDfjfXf7xMIz98nVxwoGQ%3D&reserved=0" originalsrc="http://en.www.inegi.org.mx/temas/geoide/#Downloads" shash="h8DxnpP1VC8nXP2f8gFsStShSlUAuYn+Yw+9/cyVRJGkLvhL2dkhV875hHOntzoPEl0LzSREH5ci1g/L2jHBKbSb+CgeRDyNZLp40rmS/KqWbVBzQ+VpzIpDLmgE5TnLW246HCqy2q5jjJu2pPlnKFePgZpnI1cxG9vysM/G2FA=">http://en.www.inegi.org.mx/temas/geoide/#Downloads</a></div>
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<div>The file is a text format, lat, long, undulation. It should be easy to import.</div>
<div>The reference is ITRF2008 epoch 2010 (it sounds strange to me not using NAD83x, but it is fine, right?... well, epoch 2010 instead of 2005 may be a problem)</div>
<div>Unfortunately I didn't find any transformation in EPSG from ITRF2008 (epoch 2010) to NAVD88. We should do a PROJ one for the database (or ask them to do in EPSG, but without much hope).<br>
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<div>The main problem, as usual, is the "home made" license (for everything in their webpage). It seems to be very open, but it is not a "standard" one:<br>
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<div><a href="https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fen.www.inegi.org.mx%2Fcontenidos%2Finegi%2Fdoc%2Fterminos_info_t.pdf&data=04%7C01%7Ccjmce%40lsu.edu%7C21f6ad5c27544f9d08ac08d94a914bf1%7C2d4dad3f50ae47d983a09ae2b1f466f8%7C0%7C0%7C637622810781019648%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000&sdata=f115p6f4ROTS8fr8IKTaV17gjrVCBph8bYGIIAQhHw0%3D&reserved=0" originalsrc="http://en.www.inegi.org.mx/contenidos/inegi/doc/terminos_info_t.pdf" shash="kVmTACjwRORgPcNUuKOLyBR6XI4OCQtfM034pKjGEitUXiL2//sv9HDFTBx6SlqbK1mTR+ixmaJWsEwEepQH5Fg7L7Slm9kwEYL88mZo2PgQiopC+khVkFUrlUChP68xiFI1FZreAk7uh+mBzzxA8C9mMBgUSN1Pa8A+NqYWy8g=">http://en.www.inegi.org.mx/contenidos/inegi/doc/terminos_info_t.pdf</a></div>
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<div>What should we do?</div>
<div>Maybe somebody already researched this geoid previously.</div>
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<div>Cheers,</div>
<div>Javier.<br>
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<div dir="ltr" class="x_gmail_signature">.___ ._ ..._ .. . ._. .___ .. __ . _. . __.. ... .... ._ .__<br>
Entre dos pensamientos racionales <br>
hay infinitos pensamientos irracionales.<br>
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