Thirty-nine point two degrees, a magic number to which we may well owe the gift of life here in the North. Water, like the three quadrillion gallons that make up the expanse of Lake Superior, grows denser as it cools, its molecules gathering closer and closer together as the temperature drops. That is until it reaches 39.2 degrees. At that point something akin to magic occurs. Those same molecules begin expanding again making the water less dense as it begins to freeze, arranging themselves into the intricate latticework of crystals that we call ice.
Or, put another way: ice floats. If it didn’t, our lakes would freeze from the bottom up. That simple fact allows for aquatic life to get through the long winter in relative warmth beneath a dome of ice, and continuing as a vital part of the ecosystem both below and above the waterline.
That strange property of fluid physics is worth pondering as we cross a wind-blown stretch of ice in a quiet bay on the edge of the Apostle Islands. We tip-toe across crackling stretches, slide and shuffle holding our breath across marbled ice as black as deep space, slide on our bellies like freshwater seals through caves bejeweled with more of that water turned to crystal artwork worthy of any Chihuly exhibit.
Nothing to see here - just five friends walking on the frozen roof of a lake above warmer, denser water as deep as our dreams, taking each step as if it were an everyday miracle, and it is.
— Jeff Rennicke (all photography by the author unless otherwise noted).
(Note: our trip was not to the famous Mawikwe sea caves near Meyers Beach. Those caves remain closed and unsafe. For information on those caves please check updates on the Apostle Islands National Lakeshore website.)
Your articles remind me of precious days growing up on Lake Superior and Bark Point. All seasons of the year provided us interesting, exciting and fun experiences. Thanks for being there now reminding us of those wonderful days on the Big Lake.