octoboy
I Crush Everything
My guess would be humidity in the air. As for Magikarp, I think it's kind of like Iceland being green and Greenland being icy.
This makes even more sense with the theory of magikarp as being "magi karp" instead of "magik karp". In Japanese it was called "Koiking", so the magi may very well represent its king-like appearance (crown-shaped fins), not its being magical in any way.
And surf probably just does follow the same logic as hydro pump. Though dive is an odd one.