During the deep freeze of January 2014, the shore of Lake Michigan near South Haven filled with hundreds of rounded lumps of ice, bobbing and knocking together in the waves. The Chicago Tribune shared the video as "Ice balls in Lake Michigan", and the scene quickly became one of the strangest sights of that harsh Midwest winter.
The Lake Michigan ice balls video
The clip shows a shoreline packed with pale, roughly round pieces of ice. The water is still open and moving between them, so the balls rise and fall with each wave, turn slowly and bump into their neighbours. The snowy beach behind them stays still, which makes the motion of the ice all the more obvious. Watch it on YouTube: Ice balls in Lake Michigan.
How ice balls form on the Great Lakes
Ice balls start with slush. When lake water is cooled below its normal freezing point while still being churned by wind and waves, fine needle-like crystals called frazil ice form throughout it. According to the Universities Space Research Association’s account of Lake Michigan ice spheres, the process runs like this:
- Turbulent water breaks up a layer of slush near the shore.
- Slush and frazil crystals clump together in the churning, supercooled water.
- Where wave action is strongest, usually close to the beach, the clumps are rolled and shaped into spheres.
- If the conditions last, the balls keep growing until waves push them up onto the beach.
In February 2013, ice balls the size of basketballs and weighing up to 23 kilograms (50 pounds) piled up at Sleeping Bear Dunes National Lakeshore, further north on Michigan's coast. The park's deputy superintendent, Tom Ulrich, said such balls turn up on beaches in winter "with some regularity but they seldom attain this size."
Winter 2014: a record year for Lake Michigan ice
The winter that produced the South Haven clip was exceptional. Waves of Arctic air through January and February 2014 froze the Great Lakes faster and further than in decades. On 8 March 2014, ice covered 93.29 percent of Lake Michigan, beating the lake's previous record of 93.1 percent from 1977. The Great Lakes as a whole peaked at 92.19 percent on 6 March, just short of the all-time record of 94.7 percent set in February 1979.
Ice balls form early in that process, while there is still open, moving water along the shore. Once the lake surface locks into solid ice, the waves stop and the balls are frozen in place.
Visiting South Haven in winter
South Haven sits at the mouth of the Black River on Lake Michigan's eastern shore, mostly in Van Buren County. Its South Pier Lighthouse, built in 1903 and still working, is reached from a public beach. The town is also the western end of the Kal-Haven Trail, used by snowmobilers in winter, and has a seasonal ice rink.
Enjoy the ice from the beach, not from the pier: Great Lakes shore ice and frozen piers are dangerous, and waves can sweep across them without warning.
For more winter ice and snow shapes, see cylindrical snow rollers on land and delicate crystals on a lake surface.
Related reading
- Tom Gill’s Ice-Covered Lake Michigan Lighthouses
- Yellowknife’s Hot-Water Cloud in Extreme Cold
- The January 2014 US Cold Outbreak: Forecasts, Observations and Winter Impacts
- A Wisconsin Cold-Weather Stunt in Its Original Setting
- New York’s January 2014 Snowstorm in Time-Lapse
- North America’s January 2014 Cold Outbreak on a Globe
No comments