Yo, Don:
You can't do that, but you CAN mitigate the strength of sunlight in OpenGL.
If you turn the sun intensity down and the ambient intensity up, the contrasting light effect is reduced.
Likewise in rendering: a second sun object manually set to shine from a prescribed location can "fill" or neutralize strong shadows cast by the main sun.
PS: Send us your Google Earth coordinates so we can see your place in the Turks....
Dwight Atkinson