NTT communications

You may feel that the sky over Japan is less blue, if you are from drier countries. When I was in the Midwest, where is less humid than Japan, I was impressed with the intense blue sky. And, of course, vice versa. This seems not a mere subjective perception.

The linked article below also supports my belief. Water vapor particles in the atmosphere seem to make the sky less blue. I took the pic just after the rain let up. So the air contains ample amout of water molecules, and few dusts since the rain washed them away. What do you think of the color?
http://www.findarticles.com/p/articles/mi_qn4196/is_20011002/ai_n10731255