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<div class="moz-cite-prefix">On 10/09/16 20:23, Colin Smale wrote:<br>
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<blockquote cite="mid:50c2743a463dff9f9880ab446f7f4b8d@xs4all.nl"
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<p>On 2016-09-10 18:55, Oleksiy Muzalyev wrote:</p>
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<p>Latitude and longitude are physical values, they will never
change for a house on Earth, no matter what. They do not
depend on politics, economics, linguistics of the current
moment.</p>
<p> </p>
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<p>You sure about that? Plate tectonics means that everything is
in motion, albeit slowly. On top of that there have been a
couple of "adjustments" to WGS84 which have caused coordinates
to change.</p>
<p>//colin</p>
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<p>Indeed, 2 - 5 cm per year. It is a lot. I did not think they move
so fast. Two-five meters per century. Then if we use this method,
a marker should be pointed initially to the middle of a house, so
that in a hundred years it is still pointing to its edge.<br>
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<p>However, street names change too, - for example:
<a class="moz-txt-link-freetext" href="http://novgorod.me/media/live/2015/04/AS9dCvAZDuY-1-600x310.jpg">http://novgorod.me/media/live/2015/04/AS9dCvAZDuY-1-600x310.jpg</a> ,
sometimes several times per century as on this photo. Not even
street name, but even language and alphabet changed three times.</p>
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<p>I could not find out though how significantly coordinates changed
with "adjustments" to WGS84, and if such adjustments will
continue.</p>
<p>Best regards,</p>
<p>Oleksiy<br>
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<p><br>
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