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Is it true that military branches (navy, airforce) from around equator use a grid-square reference system for radars and have issues when going further north, while triangle-based reference systems are a really good model in polar countries that doesn’t scale well when going South?

It’s a problem so predictable that I can’t believe I have been told the truth, and it’s impossible to find the right keywords to search that on Google ;)

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The military does use a grid square reference system, Military Grid Reference System (MGRS), and to resolve the issues when sufficiently far north, the grid squares stop being aligned with the latitudes and longitudes, but rather just sit lined up with the 0/90/270/180 longitudes, as a sort of circular cap cut out of grid paper. (Properly speaking, it's Universal Transverse Mercator (which is a series of 60 Mercator projections) between 80S and 84N, and Universal Polar Stereographic near the poles).

Best bit of weirdness about UTM is the exception made for zone 32V so that Norway fits into a single zone, see: https://en.osm.town/@opencage/109694749637123570

There's a similar weirdness for Svalbard, which results in 32/34/36X not existing.

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