Because of the temperature difference, arid areas near the coast suck ocean clouds in, where at night they cool and rain out. The freshwater can then be collected and channeled. Nature just needs a little nudge to get the saltwater droplets a few feet off the surface during sunlight hours, then takes over. Arid areas like California could economically be turned into a rainforest.
I once dated a girl from northern California, who sincerely believed that redwood forests sucked the fog in off the Pacific, and that cutting them down would cause a drought.