Slope Calculations for Dummy Map Readers

Channel slope

In the bad old days before Google's Panda update made it impossible for people writing quality online content to make any money from their efforts, the internet was awash in people writing crap content at sites like Helium, AssociatedContent, Lunch, and eHow.com; all reasons Google installed the update in the first place. Although eHow was the poster child for the content Panda was intended to kill, it's one of the few such sites still functioning. If you want to see the sort of rubbish that made the site a laughingstock, the managers have left much of it in place. We're talking about content such as that written by contributor Jennifer Fleming, who's visited some pretty awful content on the 'net; including today's award winner, "How to Calculate Channel Slope" (now residing at BizFluent.com... ooops, Sciencing.com).

Unlike most of Fleming's content, which regularly incorporates oversimplification of complex subjects and gross misinterpretation of anything remotely "science-y," Jennifer more or less got this one right... we think. The reason we said "we think" is that, perhaps to meet eHow's self-imposed minimum word count and perhaps because she's simply a lousy writer, it's difficult to untangle the syntax to get to the point. The point, by the way, is that channel slope is the rise over the run: the difference in elevation between two points divided by the distance between them measured along the course of the channel. 

Jennifer gets the definition pretty much right when she explains that "Slope or gradient is the vertical distance divided by horizontal distance, and channel slope is how far a channel drops over a horizontal distance..." ...which is pretty much what we just said, although she really should have mentioned measurement along the channel instead of as the crow flies. But then, as is her custom, Fleming expands on this in her scientifically illiterate way: "Essentially, a channel slope is the valley between the peaks of elevation created by a stream." "Peaks of elevation"? WTF does that horse puckey even mean?! Why she couldn't leave well enough alone remains a mystery... Getting to the point, though, Jennifer instructs her readers to

"Find the creek for the channel. Find the source and mouth of the creek. Begin tracing the blue line on the map denoting the creek. Document the elevation line starting at the source and following the creek upstream to each cross of the contour line."

...which is wrong in so many ways: for instance what could "find the creek for the channel"? possibly mean? and why do you need to "document the elevation... to each cross of the contour line"? In case you wondered, you simply note the elevation at the two ends of the channel section you're observing -- not at each "cross of the contour line." Jennifer's obviously hung up on these "cross[es] of the contour lines," since she next instructs you to

"...measure the distance along the blue line of the creek from contour line 1 to contour line 2... Repeat this for all adjacent contour lines to the source of the creek..."

Which makes us wonder why not just measure the distance from the start of the section to the end instead of all these measurements? Because Jennifer is a dumbass, that's why... When all is said and done, Jennifer's "answer" is more or less correct: divide the rise by the run (though she insists on stating it in percent instead of the more common feet per mile or simply a decimal value). 
Many of our college professors refuse to give full credit for getting the right answer unless a student shows his or her work. After all, guesswork doesn't make it in the real world - you have to know the facts. We say that getting the right answer (more or less) but completely screwing up the "work" means that Jennifer Fleming is, once again, highly deserving of the accolades accorded to her as our Dumbass of the Day.

Note: Jennifer cited a source for her "knowledge" (we use that term very loosely). something called "sotoyome" -- she's such a dummy (and so's eHow) that she hosed that information, too: it's actually "sonomarcd"! What an idiot!

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