National Atmospheric Deposition Program
LONG BEACH — If you’ve ever wondered why iron objects left outside in Pacific County rust so quickly, wonder no longer: The wind delivers about 8 1/2 tons of sea salt per year to each of the county’s 933 square miles of land.
“How much salt is naturally in our environment, particularly salt that reaches the ground in precipitation or by dry deposition?” University of Washington Professor Cliff Mass asked Feb. 12 in his popular blog. “The answer is going to surprise you. A lot of salt is falling out of the sky! In fact, probably more than being spread by state and local departments of transportation.”
Mass explains the salt comes from breaking ocean waves. “The ocean is salty, of course, and when waves break or when wind produces spray, the air is filled with salt water droplets. These droplets can evaporate, leaving small particles of salt in the air. Here in the Northwest, salt particles can be easily blown inland by the prevailing westerly winds and brought back to the ground by precipitation or even dry settling (deposition).”
According to the professor’s analysis, maritime areas of Washington state are constantly under the salt shaker to the tune of 30 kilograms of salt per hectare per year — which translates into 17,130 pounds for each square mile of land area in Pacific County — or 26 pounds per acre per year.