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.

Another view through the trees at the top of the cliff in northern Door County, Wisconsin

Another view through the trees at the top of the cliff in northern Door County, Wisconsin

Me atop a pile of ice at the "ice shoves" of 2015, Door Bluff County Park, Wisconsin

Me atop a pile of ice at the “ice shoves” of 2015, Door Bluff County Park, Wisconsin

Ice piled up just off Door Bluff County Park, March 26, 1015

Ice piled up just off Door Bluff County Park, March 26, 1015

The blue ice looks downright unnatural.

The blue ice looks downright unnatural.

Huge chunks of blue ice pile up against tops of the 30-foot high cliffs.

Huge chunks of blue ice pile up against tops of the 30-foot high cliffs.

4 comments

What do you think? Please comment!