Last October, Antarctica set an all-time record for HIGHEST ever sea ice extents (area) at 19.5 million square kilometers at maximum.
This spring, Antarctica sea ice set a second-high highest sea ice minimum extents.
And, Antarctic sea ice extents has been steadily increasing ever May 2011 through ALL seasons of the year: If this rate of increase continues - which is admittedly uncertain - the Cape Horn passage will be blocked by Antarctic sea ice within 8-10 years!
Not only Lake Michigan, but also the channels (where the rivers meet the Lake) have been frozen over. Not that walking out on the river ice is a good idea of course...