Winter on Ice

There has been a decent amount of snow this winter. Still, recent winters feel different than the winters of my childhood. While there have been years with large snowfall amounts over the past decade, the snow does not linger the way I remember. Especially this year, we have experienced a consistent cycle of freezes and thaws.

This pattern has impacted the ice cover of Lake Michigan and the many inland lakes in Michigan. The lack of ice on Lake Michigan has led to lower lake levels. It may be impacting both winter and summer rainfall patterns. The Muskegon Chronicle recently highlighted the change (here). The article discusses a National Science Foundation study which concludes that there are 16 less days of ice cover today then there was thirty years ago.

During my regular duties at work, I recently came across a sign of this change. Our department is responsible for four sets of aerial photography of Ottawa County over the past thirty years. In order to preserve the photos and make it easier to produce copies of the photos, the mylar sheets have been scanned into digital photos.

In Michigan, aerial photos used for property review purposes are typically obtained in April, after the snow has melted and before leaves grow on trees.

I am currently reviewing the photos as a quality check. As I was reviewing the 1984, I began to notice a strange pattern which I thought was a imperfection in the mylar sheet. As the pattern appeared in later photos, I realized that it was not an imperfection. It was ice.

This lingering ice is isolated to our 1984 photos. I have not been able to locate any freely available climate summary of 1984, but I'm guessing that there must have been a large ice build-up that year and a consistently cold winter.

I know that this year when we get new photos that there will not be any ice. I can not imagine that photos we obtain in the future will have ice.

Is this another sign of climate change, a companion to the retreating glaciers in Europe, the Andes, and Glacier National Park? Or it is just evidence of a very cold year in a normal cycle of cold. I'm not sure, but it definitely feel different.

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