Latitude and Longitude for Dummies, the Rewrite

Note 1) convergence at poles,
2) angle measurement

Several of the more than 1,200 freelance posts we've featured in this blog have disappeared since their initial selection for the singular award of DotD. A few were deleted (or moved) by the writer, several were at now-defunct websites, and most of the rest were dropped by Leaf Group or disappeared by HubPages because someone discovered they were sub-par. A few, however, have met the tender ministrations of the Leaf Group rewrite team: "professional freelancers" assigned to spiff up old copy. We'd like to think it's because someone follows us, but it's probably because some SEO type said they needed "fresh content." Unfortunately, not all the rewrites are improvements on the originals: let's see how well Rachelle Dragani performed with the Sciencing.com post "How to Read Longitude and Latitude."

Dragani's rewrite showed up in June, 2018, replacing a post written by Alan Li (we discussed that one here last year). Rachelle's rewrite pretty much gutted Li's version, but although more literary, her post was little more accurate than the original. Dragani introduced the topic by telling her readers that,

"Longitude and latitude are tools that pinpoint any location on Earth. With the dawn of GPS systems and smartphone maps, it’s not as common to map out locations using long numerical coordinates. But the latitude and longitude system is the basis of many of those mapping apps..."

First, GPS systems aren't "apps." Second, and far more importantly, lat-long is not the basis of the GPS system: a network of 24 satellites and some tedious, though fairly simple mathematics are the basis of the "mapping apps." Latitude-longitude coordinates are merely one method of communicating locations based on satellite navigation, the same as UTM, what 3 words, or any other coordinate system. Dragani goes on to further confuse the issue, telling us that,

"Under the longitude and latitude system, the Earth is divided into a grid of horizontal and vertical lines."

No, the planet is not divided into lines. Maps and globes of the Earth display a grid of lines, but those are not "divisions": they are imaginary reference lines. And while we're at it, latitude and longitude do not represent "horizontal and vertical": they represent north-south and east-west. Specifically, they represent the angular coordinates of a point on a sphere, measured in portions of a 360-degree circle from two arbitrary planes at right angles to one another. For similar  reasons, Rachelle's claim that,

"Each line of latitude both north and south of the equator increases by one degree..."

...is equally nonsensical. Dragani also explains that,

"To read the coordinates of any location, start with the number of degrees on the latitude line, and clarify whether it is in the Northern or Southern Hemisphere. The Earth is nearly 25,000 miles around, so once divided into 360 degrees, it means each degree is about 69 miles wide."

That statement is correct: simplistic, but correct. What it leaves out, and what is not mentioned anywhere else in the post is that lines of longitude converge on the poles. In other words, one degree of longitude covers about 69 miles at the equator, but becomes ever smaller as you approach either pole. Dragani misinforms her readers about the GPS system, treats latitude and longitude as if there are lines printed on the surface of the Earth, and fails to mention one of the most important facts about the lat-long system. Is it a good rewrite? It's better than the content it replaces, but it's still worthy of a Dumbass of the Day award.

Confidential to RD: if we were to provide the lat-long of Wrigley Field, we'd use home plate (41.947904, -87.655818); not a random spot in short left-center where Texas-leaguer might land.

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