Cruise Ship Pollution
This picture was originally supposed to be a picture of harbor seals on the float at the Douglas Harbor.
It turned out to be a shot showing just how horrible cruise ships are. All that crud in the air is from them, and they alone. You can even follow them around for hours after they've gone past. Contrast the blue smoke coming from the ship with the white steam rising from the water treatment plant on the right.
If you know anyone who's against large ship emissions standards, send them the link to this photo.