[HOT] What's water?

Pat Tressel ptressel at myuw.net
Mon May 4 03:48:53 UTC 2015


I'm seeing some rivers mapped in areas that didn't have high-res imagery,
that (in the DG imagery) cross over dry land, or through areas were tree
tops are visible against a dark background that could be either water or
shadow -- it's a dark gray-purple.  What I'm interpreting as the actual
river channel is more turquoise and has (what look like) white rapids.  The
imagery has no clouds, and land looks fairly dry, so this imagery may,
perhaps, be dry season.

Note the previously mapped rivers in this area are very rough -- points are
far apart -- which implies they were mapped from low-res imagery.

Some questions:

Is there a large change in water volume in rivers during the dry season?
I'm wondering if water recedes to the deepest channel, and does show more
whitewater then.

Do trees grow in standing water (deep enough to appear dark) in Nepal?
That's not unheard of -- it's true in the Everglades in Florida.  Or is an
area with treetops and dark between more likely dry but shadowed?


-- Pat
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