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Author Topic: Regional/Local Impacts of Global Warming in the Great Lakes  (Read 8163 times)


  • Frazil ice
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Re: Regional/Local Impacts of Global Warming in the Great Lakes
« Reply #50 on: January 11, 2020, 05:17:02 AM »
Great Lakes Ice Cover Nearly a Record Low For Early January

"Ice cover throughout the Great Lakes is nearly a record low for early January because warmer than average temperatures have dominated the region so far this winter.

The total ice coverage on the five Great Lakes was 1.5% on Tuesday, or the second lowest for Jan. 7, according to NOAA's Great Lakes Environmental Research Laboratory (GLERL). Ice cover on that date has averaged about 13.9% since records began in 1973.


Great Lakes ice cover usually peaks later in winter, sometimes in late February or early March. The current conditions are not reflective of what the peak might be in the next month or two because that will depend on long-term weather patterns.

Last year started out nearly as slow, but then colder conditions moved in and the ice cover peaked at 80.9% in early March. That's much above the average yearly peak of 55.7%.

On the flipside, early January 2017 had about 3% ice coverage. Persistently mild temperatures through February that year prevented ice growth and the season only had a maximum peak coverage of 19.4%.

What really stands out is Lake Erie has no ice coverage right now.

Lake Erie is the shallowest of the Great Lakes, which usually makes it freeze up fastest. The lake's ice coverage has averaged 27.7% by Jan. 7.

The lack of ice on Lake Erie could keep it primed for lake-effect snow deeper into the winter compared to normal unless more persistent cold air arrives soon.

All of the other four Great Lakes are also trailing behind their average ice cover for this time of year."

Attached is a graph showing the date of maximum ice extent on Lake Superior, from 1973 to 2019. Note that 50 days is Feb. 19th and 63 Days is March 4th.

Line is five year running average.

Shared Humanity

  • Young ice
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Re: Regional/Local Impacts of Global Warming in the Great Lakes
« Reply #51 on: January 11, 2020, 04:28:17 PM »
I live in Chicago and beaches line the shoreline. They are being destroyed this year and many will not exist this spring. On my drive to work this morning, there is a gorgeous beach house built in the early 1900's on the south side that has waves rolling through it. All of these old structures are masonry and brick with more roof than walls so this one will survive the storm. The beach is another story.


  • Nilas ice
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Re: Regional/Local Impacts of Global Warming in the Great Lakes
« Reply #52 on: January 18, 2020, 12:04:02 AM »
Chicago More Vulnerable to Climate Change than Miami, Says ‘Death and Life of Great Lakes’ Author
At the point when Egan was writing his book, which synthesizes a decade of his reporting on the lakes for the Milwaukee Journal Sentinel, Lake Michigan was at a near record low. In 2020, it’s at a near record high.

“In the past, it would take a quarter-century to go from low to high. We just did it in five years,” Egan said.

Going back to the 1840s, Lake Michigan has reliably peaked or bottomed out within 3 feet of an average level, for a total 6-foot swing. “Chicago was built on that assumption, so was Milwaukee,” said Egan.

The new norm could be 5-foot variations, for a 10-foot swing, he said, and that’s cause for alarm.