Today's Landsat week post brings to you: art!
I really don't know how to better describe this wonderful picture. But I will do my very best to try.
While on first sight this could be many things, even biologically grown structures, this shows a river delta. To be exact it's the Yukon River Delta in Alaska and forms the Yukon Delta National Wildlife Refuge. The delta makes up one of the largest in the world
The Yukon river originates in British Columbia, Canada and crosses the Yukon territory, lending its name. Then it crosses the border to Alaska and flows into the Bering sea. When water from the Yukon hits the Bering sea, it is no longer confined to a channel. This decreases the flow energy of the water. Therefore, the water loses some capability to carry sediments. These sediments are being deposited at the mouth of the river, forming the first depositional state of a delta.
Now something interesting happens. The deposition of sediments at the mouth of the river elongates the channel. Yet the change of elevation stays constant. Hence, the slope decreases leaving the path of the river unstable. This leaves two physical options to retain stability. The river can ?take a shortcut? and by that shortens the path and increases the slope. Alternatively, what happens is that the decreased flow decreases the stress on the river bed. Then deposition happens in the river bed, decreasing the depth of the river. Actually this makes it more likely for the river to make the ?shortcut?. Often both channels stay active forming a distributary network. Those are branches of rivers flowing from the main river.
Another thing that happens, is that the river gets in its own way at the mouth. It deposits sediments in the middle of the channel, forcing the water to find ways around the new barrier.
This way the river starts to separate into several branches, forming complex structures. These structures are one part that (for me) make the beauty of this image. It borders to the beauty of a Mandelbrot sets.
Obviously this picture is a so called false-color picture. It is a composite of different wavebands that were combined for this final picture. If you would like to have a look at how these pictures are set up head over to the NASA webpage: http://amplt.de/ld
This picutre placed number 2 on the big vote at NASA & USGS: http://amplt.de/l8
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