Degrees and Meters for Geography Dummies

great circle path

From time to time the Antisocial Network research staffers come across content that supposedly addresses questions that, to be honest, are damned near unanswerable (most commonly at eHow or some other member of the Leaf Group of niches). Sometimes it's because of the wording, but it's usually because of a lack of context. Take, for instance, a question about "How to Convert Distances from Degrees to Meters"¹: we suppose that might be a badly-worded question about the length of an arc, among other queries. Sciencing.com contributor Emile Heskey (back when he was using the name Andy Williamson) decided it had something to do with latitude and longitude on the Earth. Hmmm... maybe not...

Heskey, who trained in history, politics and Middle Eastern studies (but not math or geography), therefore "explained" that

"As measurements of latitude, degrees often appear as if they cannot be converted into meters or kilometers. The slight flattening of the globe at the poles means that degrees are not constant throughout the world. The extent of the discrepancy, however, is so slight that scientists work from a standard degree, which can easily be converted into meters. Knowing this will help with navigation and will improve your ability to find locations based upon latitudinal readings..."

...which is, of course, total bull. First, a latitude is pretty much useless without a longitude and second, the question was about conversion, not location. Whatever... Emile proceeded to tell his readers to convert the measurements from degree-minute-second format (DMS) to decimal degrees (DD), which took this dumbass a total of 133 words! Once that's out of the way, Heskey says to "Multiply the number of degrees by 111.325. This is the standard distance, in kilometers, of a degree. For example, if you have 2 degrees, this is 222.650 kilometers. To convert this to meters, multiply by 1,000. So, 2 degrees is 222,65 meters."

OK, so fine... people who like accuracy probably cringe at that "standard distance, in kilometers" rubbish; but it's close enough for government work, especially with Donald Trump in the White House (or at Mara Lago). Anyway, when you come right down to it, that information is well-nigh useless. What good is this "information" without context? What good is it to know that if you "have 2 degrees" – whatever that means – it's 222.650 kilometers? So what? That's not to mention that 222.650 kilometers multiplied by 1000 is not "222,65 meters"...

No, Heskey wanted his fifteen bucks so he just pounded out some bull. He had jack to say about measuring distances on a sphere using great circles (e.g., the haversine formula) and nothing to say about degrees of longitude, as well as making a pretty serious mathematical (or was it proofreading?) error. That's plenty to qualify Emile/Andy for his Dumbass of the Day award...

¹ The original has been rewritten by the Leaf Group team, but you can still see Heskey's original version using the Wayback machine at archive.org. Its URL was   ehow.com/how_7858322_convert-distances-degrees-meters.html

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