Wednesday, September 25, 2013

Jackson, Mississippi

I'm a pretty big fan of oxbow lakes (and the process of their formation!)  Unfortunately, oxbow lakes probably don't have a lot of "fans" and probably don't even hold most folks' attention for more than a few minutes.  However, I'd like to argue that they really should.  Why?

1) They can happen in your lifetime!  Unlike mountain building, continental rifting, volcanic island-chain formation, and ice age cycles, oxbow lakes can easily form and change the physical geography of a place in a relatively short amount of time.  They share a category in this regard with things like glacial retreat and natural disasters (only the implications of a meander cutoff aren't as dooming, so there's another plus.)

2) They ignore the petty politics of geographical borders.  Thinking about splitting from your neighbors?  Why not use the nearby stream as the geographical border between your newly divided lands?  That's easier than having to put up a fence, right?  Think again!  That stream might decide to move at some point!  What happens when that fancy apple orchard growing inside the meander gets cut off and ends up on your neighbor's side of the stream?  Who owns your precious apples now???

3) They're all about taking shortcuts.  Who doesn't love a shortcut?  Point A and Point B will briefly be a little closer together before the continuous erosion of cut banks extend the remaining meanders outwards.

4) They influenced my decision to keep this blog going.  Last time I blogged about a meander cutoff it spread all over Google+ and Twitter and was shared by a number of other science and non-science bloggers.  To this day, that blog entry is my most popular – being viewed almost 100x more than my next highest viewed entry.  I'm extremely proud of this, and it was one of the reasons I kept this blog going.  Oxbow lakes saved my life blog!

That lengthy introduction was to lead up to this new oxbow lake blog entry!  The occurrence is just south of Jackson, Mississippi on the Pearl River and looks great in this imagery:

Here's a good example of county boundaries (shown as the thin green line and probably designated over a century ago) that were ignored by the Pearl River:

You can find it yourself on Google Earth using these coordinates:     32°11'20"N  90°12'00"W  

More info: Wikipedia

Check back in two weeks to see a large scar in Wisconsin!

Wednesday, September 11, 2013

Aq Qala, Iran

Unfortunately, I don't have a whole lot of information to associate with this imagery.  I was browsing Google Earth with my free time and exploring northern Iran when I came across a flood just outside of the city of Aq Qala in the Golestan province.  I tried looking up "March 2012 Golestan floods" and other related search terms but couldn't find anything in particular that detailed the extent of the flooding.  If you happen to find anything, feel free to leave a comment below.

What is most notable about this image to me is the extent of flooding in the low-lying farms south of the main river channel.  You can see how the flood waters travelled up a small tributary stream that connects to the river in the northeast portion of the image.

The following gif shows June 2003, September 2007, October 2012, and March 2012:

You can find it yourself on Google Earth using these coords:     37°00'N  54°30'E  

More info from sources referenced: Wikipedia

Check back in two weeks to explore another oxbow lake formation in the Deep South!