Originally Posted by Gidji
Happens to me sometimes. I belive its the height :) All that air pressure and pollution just rises right up and makes it worse.
Actually, I think air pressure/pollution decreases with altitude. Hence the higher pressure maintained within a flying airplane, and "clean mountain air."
I have that problem, too, occasionally. More often and more noticable in the winter. I think it has to do with the wind, as Saskia said, but that humidity (or lack therof) can make it better or worse. It gets really humid in the summer, and really dry in the winter, at least in my area, so that explains the seasonal change. Maybe you guys who have the same thing all year live in drier climates than me?