Instead of assuming that the pole stands 1 mile above the earth, I'm going to assume the pole is actually 1 mile below the surface of the ocean, with the top sticking out a few feet above it. I would tie one end of the rope to each can, and throw one can to a crew member on a passing barge. Hopefully the can will hit him or land near him and, therefore, get his attention so he can alert his captain to turn the boat around and rescue me and the dog. When we pull into port, I and the dog will disembark and will once again be safely on the ground.