How thick is the ice on Madison's lakes? Researcher Ted Bier almost didn't have enough drill to find out this week.
Bier takes ice depth samples as part of his work for the UW-Madison Center for Limnology, and he was out in the middle of Lake Monona on Thursday to get a reading. The drill kept going and going until finally reaching water underneath the ice.
When they extracted the ice core that you can see in the photo above, the depth measured 65 centimeters, more than 25 inches.
"Generally speaking, all the lakes in the area had 2 feet or more of ice on them at some point in time this winter," Bier said. "That's 40 to 50 percent thicker than we usually have. I've been here 13 years and it's the thickest I've ever seen."
In records dating to 1996 from the North Temperate Lakes Long Term Ecological Research project that Bier works with, the previous high depth on Lake Monona was 50 centimeters (about 20 inches) in 2008.
Bier said a measurement for Lake Mendota a few weeks ago showed 63 centimeters of ice, just over 2 feet.
Here's a look at the recordings over the years on lakes Monona and Mendota:
Barring a sudden heat wave, it's going to be a while before the lakes thaw, Bier said.
It'll take a good string of temperatures in the 50s and 60s with sunshine and wind to get the ice off the water, he said.
"It's going to take a lot of heat energy to melt all that down," Bier said. "People get panicky when they see the ice fishermen out there, 55 degrees, the sun's beating down, they're sitting there in shorts ice fishing. The truth is they're just fine there."
Bier's ballpark guess on the thawing of the lakes, given the current ice depth and normal spring weather conditions, is between April 7 and April 15.
The median date of Lake Mendota's opening is April 4, and if the thaw doesn't take place until the late end of Bier's estimate, Mendota will have had 121 days of ice cover, the most since 1978.
That would go against the trend of shorter ice seasons on Madison's lakes as time goes on. The 158-year median is 105 days, and Friday is the 89th day of ice cover on Lake Mendota for the 2013-14 season
Here are the recordings for Lake Mendota from the winters of 1855-56 to 2012-13, with trend lines showing an earlier date of the ice thawing and fewer days of ice cover:
In December, we showed that Madison's lakes froze earlier than the median. Lake Monona froze on Dec. 10, while Lake Mendota closed on Dec. 16.