Chow - Suspended solids/materials/plankton stain the water and are moved/positioned by currents. Darker areas adsorb light thus warm up and achieve warmer temperature. If you look at the modis pictures you'll see various degrees of staining with the heaviest near river/creek inflows. Dark Brown, light brown, dark green, light green, blue-gray and blue/clear. Browns are mud, greens are algea, blue is freek-N cold. Sustained winds will move it around as they locally alter the general ccw current of Big-O along the S shore.
Tom B.
(LongLine)