Saturday, October 22, 2016

You're So Vein: Strahler Stream Order Classification System and Open-Source QGIS

       A colorful new map shows the complicated network of rivers and streams in the contiguous United States, dominated, of course, by the Mississippi River catchment area, shown in pink below.
  


       The map was created by Imgur user Fejetlenfej, using open-source QGIS (Geographic Information System) software.






      The map creator also used Strahler Stream Order Classification, with higher stream orders indicated as thicker lines. 




      There are 18 major river basins in the 48 states of the contiguous US, but, as noted above, much of the map is dominated by the massive catchment area for the Mississippi River, including the Upper and Lower Mississippi River Basins, along with Missouri River Basin and the Arkansas-White-Red Basin.




      The map is not perfect (note the straight-line, perpendicular, feathery lines within the Great Lakes, rather than solid bodies of water)






as well as the inconsistencies in the Columbia River-Snake River Plain area.





        The most exciting part of the map, for me, though, is that all the data were obtained gratis and put on an open-source GIS platform. It makes a dazzling display (overlooking those few issues). And people are buying it on Etsy! Maps getting good press is always exciting. 




     Maizie (pictured here on her 10th birthday Monday) and I are off to enjoy our 80 degree October day. Maybe we'll even hike streamside ;-) with a stream of consciousness running in our heads. . .

     



Are you live streaming streams this week? Steph






25 comments:

  1. Thanks for shining a spotlight (German: Strahler) on the system for measuring the branching complexity of mathematical trees and their wetter geographical counterparts. How does QGIS define a stream? How much of the year does it actually have to contain water? Or are these streams just theoretical constructs, based on how water would flow downhill from any point, based on topography?

    I was a little disappointed that the images weren't zoomable. And those Great Lakes are bizarre.

    What's new with Zoë? Is she someplace safe, I hope?

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    1. The creator of the map says they are "permanent and temporary streams" so ephemeral stream beds are included. The guide to QGIS software is here if you want to read more.

      Yeah, zoomability is a problem.

      Zoë has decided to stay, even though the newest state of emergency in ET declares that the safety of both locals and Americans is at risk. She will be at her new site this weekend but is not telegraphing exactly where. I am guessing it will be within 40 km of Addis Ababa. We spoke briefly Friday before the line dropped off. Thanks for asking, jan.

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  2. I recommend nibbling tasty mandelbrot when contemplating half-baked ideas, like mine, about the fractal geometry of nature. As opposed to twice-baked pastries like biscotti (Italian for "twice baked"), zweiback (German, ditto), or biscuits (from Latin, you guessed it).

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    Replies
    1. Your ideas seem fully baked to me, jan! The mandelbrot looks yummy. . .

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    2. Speaking of edibles and being fully baked, we watched an interesting documentary a few weeks back, Rolling Papers, about the Denver Post's decision to name a marijuana editor. Hilarity ensues. Actually, they seem to be doing a pretty respectable job there.

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    3. Yeah, we hear all about that often. . .What I note most since legalization is an increase in 1) traffic and 2) crime in the 'hood.

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    4. So far, Maizie's been quite healthy, but I did run the pot idea by her. Perhaps canis cannabis could help down the road. . .

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  3. Happy 10th, Mazie. You look young beyond your dog ears... er, dog years.
    I second jan's concern for Zoe (sorry, umlautless!).
    I hail from the Great Upper Mississippi Basin!... a phrase that sounds majestic, except for the final word.

    LegoSays"I'veTried'Em,HaveYouTried'Em?

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  4. Thanks, Lego, for the wishes for Zoë's well-being.

    . . .And for the PMB link. Do you like the new PHC guy? A little soon to tell for me.

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    1. Too soon too for me on the new PHC MC. Very different, impossibly unfillable shoes, and all that. GK's appeal, to me anyway, is that he was a writer first, entertainer second. This new guy is an excellent musician... but I will miss weekly "News from Lake Wobegon" reports.

      LegoWhoWhenHeWasChildWasAboveAverage...WhatHappened?!

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    2. This was his best line: "Thile took a jab at both major-party candidates, admitting that he, too, had used an unsecured e-mail account once and he, too, had not paid income taxes for 18 consecutive years — 'after that I graduated high school.'"

      I agree, music was great. He sounded a little stilted at moments. . .but he'll get the hang of it.

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  5. Replies
    1. OK, but why just maps of the bottoms of lake, which you can't see unless the dam breaks or the drought worsens, rather than the land? Turns out you can buy those, too, or make your own/ (What a relief!) QGIS again, in that last link, BTW.

      When my mother-in law remarked that she like to eat on the deck in Martha's Vineyard so she could see the water, her husband would remind her, "Just the top".

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    2. Such a relief, indeed! The how-to blog is cool (but Shamblog as a name?). They would make awesome holiday gifts!

      Just the top? Clearly your mother-in-law needed a bathymetric map! ;-)

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  6. Replies
    1. Enjoyed all of them but especially Pinocchio and Grapes of Wrath.

      Thing one. Thing two. Your mother. Coming home. It's a mess, I tell you, a mess. #TrumpBookReport

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  7. October 23, 4004 B.C. -- Happy Birthday Earth! (According to Archbishop Ussher, (1581-1656))

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    1. And I just thought it was Mole Day (6:02 on 10/23).

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    2. Ussher said it was the night before October 23, i.e., October 22. And he was using the proleptic Julian calendar, which means the Earth's actual birthday was October 9 by our Gregorian calendar. Rats, again!

      Using the same sources, apparently, Maimonides calculated Day 1 to be October 7, 3761 BC/BCE (Julian, again), although it seems the actual creation didn't happen until about a year later.

      As a Pastafarian, I prefer a colander to either calendar.

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    3. So funny to discuss these details in the realm of geology where dates of +- 1 million years are no big deal.

      9 a.m., lunchtime, October 23, the night before, October 9, October 7, -- all dates +- 4.543 billion years. How about that? Works for me to Ussher in this new year.

      Great Colander/Calendar comment, jan. Pastafarians Unite!

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  8. The checker at the grocery store shook his head at my buying "ridiculous Artisanal Water," until I pointed out it was actually "Artesian Water."

    Well, well, well.

    Never mind.

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  9. Continuing our "Stream Theme," and branching off into earthquakes, the latest post on "Whose Fault Was It Anyway?: The Endorheic Salton Sea and A "New" Salton Trough Fault" is now up.

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