Pressure ridges, aka “ice shoves”
This week photos online and on the local news showed ice pressure ridges in northern Door County Wisconsin. People around here call them “ice shoves.” Some were claiming the ice was more than 30 feet high and carried a beautiful shade of blue. I decided to drive up there and check it out myself late this afternoon. My conclusion: It’s true. At Door Bluff County Park, I estimated the biggest pile I scrambled up was about 35 feet at its highest point. It was fascinating to see huge chunks rubbing against trees at the top of the cliffs. And the color! It looked as though someone dyed the clear waters of Lake Michigan blue before it froze. Unreal. The natural phenomenon of pressure ridges is caused by strong wind blowing huge sheets of ice against each other and against the shoreline until it piles up. It doesn’t happen every winter, but when it does it’s quite a spectacle.