Maps, Grids, and Coordinates, the Dummy Version

Reading map grid coordinates

One of the Antisocial Network founders worked for many years making maps. By his count, he's probably pumped out several hundred thousand (maybe a million!) big sheets of paper and/or digital representations of the earth, both its surface and subsurface features. Along the way he learned quite a bit about map projections and coordinate systems. To be blunt, he says he forgets a helluva lot more about those subjects in a single day than Sciencing.com's Tasos Vossos ever knew. Should you need any proof of Vossos' unfamiliarity with the topic, look no further than "How to Convert Map Grid Coordinates to Latitude and Longitude"
A self-described "professional journalist," Tasos was obviously out of his comfort zone from the get-go with this post. Take, for instance, the way he differentiates between grid coordinates and lat-long in his introduction:

"...it is better to use latitude and longitude than non-standard scales that may appear on certain maps. It is not difficult to convert grid coordinates to latitude and longitude, as both use a Cartesian plane..."

...both of which claims, as anyone who has ever used grid coordinates could tell you, are utter bull. Oh, yeah, and Tasos? Latitude and longitude are not Cartesian coordinates, they're spherical coordinates.

Whatever the case, Vossos clearly has no idea what map coordinates – which some people think of as UTM coordinates, but which encompass many, many projection systems – actually are. You can tell that because Tasos (with the tacit assistance of an obviously moronic "content editor") provides his readers some truly idiotic instructions. For instance, on "Regional Maps with Scales." Tasos says you should "Determine a location's position on the map based on your coordinates. For example, count from left to right and from bottom to top to locate position (3,5), where the first number is the horizontal axis value and the second number is the vertical axis value..."

It's clear that here, Vossos is envisioning one of those city maps that says Main Street is in square B5. Sorry, Tasos, that's not what map grid coordinates are: they're projected coordinates, and they're a damned sight more accurate than "B5"! When it comes to "World Map Conversion," Tasos goes even farther afield. Here. he advises readers to

"Measure the length of the x-axis in inches, starting from point 0 and ending at the left and right side of the map. This is to establish that the distance on both directions is equal and the coordinate plane is centered on the map. Repeat the process with y-axis and the top and bottom sides of the map."

But wait: it gets better...

"Divide the length of the x-axis by 180 and the y-axis by 90. This will give you the equivalent of each latitude (LA) and longitude (LO) angle in inches."

Ummm, yeah. That'll be "accurate." No, people the real way to convert map grid coordinates to latitude-longitude is to 1) determine the projection and 2) use a conversion program. Idiot! But who cares, anyway? Anyone stupid enough to follow the directions written by this Dumbass of the Day deserves to be lost!

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