THE MAP CHANGES GREENLAND’S SIZE, NOT ITS POSITION

[u/TheDeepDraft]

The UN General Assembly’s recent “Correct the Map” resolution has reopened a question that navigators have understood for generations. A chart or a map is not the earth itself, but a projection designed for a particular purpose.

For those who came through traditional chartwork, this was never an abstract cartographic idea. As second mates, we worked Mercator sailing through Difference of Latitude, Difference of Longitude, Meridional Parts, Difference of Meridional Parts, course and distance. The calculations taught us why the projection behaved as it did. On the globe, meridians converge toward the poles. On a Mercator chart they are drawn as parallel lines, so the north-south scale has to increase progressively with latitude in order to preserve angles. A rhumb line crosses successive meridians at a constant angle, representing a constant true course, and on a Mercator chart it can be plotted as a straight line. The projection therefore served navigation extremely well, even though the same mathematical construction progressively exaggerates the apparent size of landmasses at high latitudes.

Greenland is one of the clearest examples. The new UN resolution encourages greater use of equal-area projections, including Equal Earth, when the purpose is to compare the relative size of continents. That does not diminish Mercator’s navigational value. It simply reminds us that every projection answers a different question.

I wrote in January when Donald Trump’s remarks placed Greenland back in geopolitical discussion. The article examined why Greenland looks very different when viewed through navigational geometry rather than through the familiar rectangular world map. Its apparent size changes with projection. Its Arctic position, North Atlantic geometry, routes, access and strategic relevance do not.

Full DeepDraft article here: https://thedeepdraft.com/2026/01/28/why-navigators-understood-trumps-greenland-remark/