2784: Drainage Basins

Explain xkcd: It's 'cause you're dumb.
(Redirected from 2784)
Jump to: navigation, search
Drainage Basins
After a pail of water was thrown on the Wicked Witch of the West outside Salt Lake City, Utah's Great Salt Lake was measured to be 7 parts per trillion witch by volume.
Title text: After a pail of water was thrown on the Wicked Witch of the West outside Salt Lake City, Utah's Great Salt Lake was measured to be 7 parts per trillion witch by volume.


Alex Mack, the main character in the Nickelodeon show The Secret World of Alex Mack, developed superpowers after being drenched by an experimental substance. One of these is the ability to turn into a puddle of liquid.

A drainage basin is an area of land where all flowing water converges by one or more outlets to the same body of water. The comic shows a watershed map for the United States by depicting its drainage basins.

When Randall sees a map of the US's major drainage basins, he thinks of Alex turning into liquid and flowing as part of the basin she happens to be in at the time.

The title text refers to the Wicked Witch of the West, a character from The Wonderful Wizard of Oz, wherein a bucket of water is thrown on her, causing her to dissolve into a puddle. If this happens near Salt Lake City she would flow into Utah's Great Salt Lake, as its location in the Great Basin would prevent her from flowing to an ocean. If its dissolved particles are measured, a tiny fraction will be witch. Seven trillionths of the lake's nominal 18.93 cubic km volume is about 130 liters, which is approximately twice the volume of a typical human being. Randall may be approximating the lake's current, lower volume, which was 27% of its nominal volume at one point but has risen substantially in 2022-23 due to heavier rains than other recent years; or witches may be twice the size of normal people; or witch matter may be particularly dense, and double in volume when dissolved in water; or he may be including the Witch's sister, the Wicked Witch of the East, as well. The Land of Oz is described to be somewhere else entirely, surrounded by desert, and thus perhaps has its own salt-lake basin(s); but famously it is not in Kansas, from which any witch-water would have ultimately flowed down to the Gulf of Mexico via the Mississippi. It is possible that Randall's choice of Salt Lake City is referencing the Surrender Dorothy meme that LDS temples look like Oz.

There is an error in the map. The map does not show the border between Michigan's Upper Peninsula and Wisconsin; in reality, this peninsula is part of Michigan.


Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[Title, scribbled out in red:] US Drainage Basins
[New title, in red, added below:] Where Alex Mack Will End Up
[Map of the United States, the state borders in light pen; the national borders, seaboards and major lakes in black pen, plus additional boundaries as appropriate between the following labeled drainage basins:]
[Much or all of Washington, Idaho, Oregon, California, Arizona and about half of Utah:] Pacific Ocean
[Hawaiian islands, in typical US map repositioning:] Pacific Ocean
[Alaska, in typical map repositioning, below a line approximately the three quarters up from the south:] Pacific Ocean
[Remainder of Alaska:] Arctic Ocean
[Most of Nevada, the western half of Utah (including the Great Salt Lake, outlined) and about a third of California (with the Salton Sea outlined):] Great Basin
[A small patch of Wyoming, a triangle of New Mexico lying on the Mexican border and a separate thin swath through parts of New Mexico and Texas:] Various Basins
[About half of North Dakota and a small section of northern Minnesota:] Hudson Bay
[From northeast Minnesota across two thirds of Wisconsin, Michigan, a bit of northern Indiana, northern half of Ohio, and most of the eastern seaboard states of Maine, Vermont, New Hampshire, Massachusetts, New York, Long Island, New Jersey, Maryland, Virginia (not West Virginia), North and South Carolinas, half of Georgia and half of Florida (Lake Okeechobee visible):] Atlantic Ocean
[All remaining states or parts of states:] Gulf of Mexico

[Caption below the panel:]
How I still think of these maps, deep down

comment.png add a comment! ⋅ comment.png add a topic (use sparingly)! ⋅ Icons-mini-action refresh blue.gif refresh comments!


For anyone else who didn’t recognize “Alex Mack” and was confused when the first result on Wikipedia was an American football player with seemingly no reference to the joke at hand, I’m pretty sure this is referencing “Alex Mack” from “The Secret Life of Alex Mack” which was a Nickelodeon TV show in the 1990s. One of their powers is turning into water.

Thanks! 00:42, 3 June 2023 (UTC)
I know of her by way of reading Diane Castle's work, The Secret Return of Alex Mack, which basically took over the Alex Mack fanfiction scene. Hadn't heard of the original until then. 03:56, 3 June 2023 (UTC)

I need to point out: Turning into a puddle of liquid is not a superpower. Anyone can do that. Turning back into a solid human again afterwards is the tricky part. ~ Xxj (talk) 04:12, 3 June 2023 (UTC)

I think turning into a puddle of liquid at will counts as a superpower. 04:23, 3 June 2023 (UTC)
Most things which a typical person does are typically done at will (other than breathing, sleeping, sneezing, and posting comments on the internet). ~ Xxj (talk) 04:52, 3 June 2023 (UTC)
Found the editor who has never had to dispose of a body. 08:48, 3 June 2023 (UTC)

Man I thought this was about the kid who jumped off the cruise ship on a dare this week and got pulled under, and was really weirded out that he would joke about that, really happy to see I was dead wrong.

he got a Darwin Award, not an XKCD comic 18:47, 3 June 2023 (UTC)

"approximately twice the volume of a typical human being"—that implies there was already a witch in the lake previously. After we add the wWotW, there are two dissolved witches. 04:44, 3 June 2023 (UTC)

It's Utah. On the basis of that alone, I'm surprised that there was only one. Vikinghelmet99 (talk) 05:39, 3 June 2023 (UTC)
The first witch was famously house-struck, not 'melted'. (Then sublimed, though perhaps condensed/redissolved off-screen the next time it rained.) 09:33, 3 June 2023 (UTC)

Oz is "famously not in Kansas" -- ha! Nicely done.

I didn't know what Drainage Basin was. I first thought it meant which ocean will come and cover this part of land if global warming continues. 2503: Memo Spike Connector (talk) 06:33, 3 June 2023 (UTC)

If it goes badly enough, that'd be the Neo-Panthalassic Ocean... ;) 09:13, 3 June 2023 (UTC)
Funnily enough, that's also a valid interpretation of a map like this (if your definition of "global warming" is expansive enough to include events like the Europa-Dutch dumping all their world's volatiles on us). Water runs off in exactly the same direction from which the sea would rise, so anywhere in the Mississippi Valley, for instance, would get flooded as an extension of the Gulf of Mexico. The endorheic basins (on this map, "Great" or "Various") are exceptions: they're areas which would flood more catastrophically due to water running down into them, as in Time. 01:17, 4 June 2023 (UTC)
While true, watershed maps abstract away information about elevation, which is more important for predicting what sea level rise will do than drainage. It's complicated by river flow volume and speed, geographical features, etc., but never significant more than a few hundred km above an estuary. Basically, if and only if the river has measurable tides, it will be affected by sea level rise (that almost goes without saying that way.) So Florida will be a lot more screwed than 90% of people's local Mississippi. 11:51, 4 June 2023 (UTC)

The explanation says: "Seven trillionths of its 18.93 cubic km volume is about 130 liters, which is approximately twice the volume of a typical human being" There have been stories recently that the water level is way down. Does that volume take this into account?

As a resident of the US Midwest, I'm minorly annoyed by the missing drainage "leak" from Chicago to the Gulf of Mexico due to the reversal of their river (first time commentator sorry for any edit error!) E sandrs (talk) 13:49, 5 June 2023 (UTC)

re: the change of "swathe" to "swath", and the summary explanation of tte Grammarian reason (that one is a noun, the other a verb)... Well, I'll accept that I was incorrect, but not in that way. I'm British and I honestly didn't know that (noun) "swathes" had an alternate Leftpondian spelling.

(Or pronunciation. Not sure I'd pronounce "swath" as /sweɪð/, ever, and I'd never say /swɒθ/ even for the mowing "swath", but that might just be my specific regional vernacular on top of being generally Rightpondian.)
I'm happy to be corrected(/Americanised, not necessarily the same thing), but I'd not like that kind editor to think I did it 'wrong' for the wrong reason. 16:59, 5 June 2023 (UTC)

To add to the list of pedantic errors: there's a mountain called Triple Divide Peak in Glacier National Park (in NW Montana) where water from that mountain can go to the pacific, the gulf of Mexico, or Hudson bay. Technically the Hudson bay basin must extend into Montana at least a little bit. 14:20, 10 June 2023 (UTC)