Encore - Lake Michigan Ice Balls Recurrence

November 02, 2019


KAScott_20140101_6598-MsnToday and every Saturday Earth Science Picture of the Day invites you to rediscover favorites from the past. Saturday posts feature an EPOD that was chosen by viewers like you in our monthly Viewers' Choice polls. Join us as we look back at these intriguing and captivating images.

Photographer: Ken Scott
Summary Author: Ken Scott

Ferbuary 2014 Viewer's Choice The photo at top shows a crop of ice balls just deposited from the frigid waters of Lake Michigan during the polar vortex event of January 6-8. These nearly spherical concretions accumulated along Sleeping Bear Dunes National Lakeshore, on the northeastern shore of Lake Michigan. The ones featured here are somewhat smaller than the basketball-sized spheres that blanketed the shore last winter.

Ice balls form where water turbulence breaks up a layer of slush. Click here for animation. Slushy ice mattes and frazil ice accrete in the wind-whipped supercooled water. The mattes eventually form into rounded lumps and will continue to grow until big waves push them on shore or until they end up in a protected inlet - photo at left.

Photo Details: Camera: NIKON D600; Lens: 24.0-85.0 mm f/3.5-4.5; Focal Length: 28.0mm (35mm equivalent: 28mm); Aperture: f/11.0; Exposure Time: 3.000 s; ISO equiv: 800; Software: Photomatix Pro 5.0.