Northwoods Lake Study Aims to Give Insight to Future Lake Health in Warming Climate
Right now, there is a lake in Vilas County that has no snow on it.
Researchers based out of UW-Trout Lake Station in Boulder Junction use shovels, snowblower, and plows to keep it clear all winter long, leaving the thick ice exposed.
It’s the second year of field work for the study that is looking at the impact of what no snow or ice cover could mean for the health of lakes in the Northwoods. WXPR first told you about study last winter on The Stream.
“This year we actually had freeze up. You might recall that the lakes this year froze really nicely before it started snowing,” said Hilary Dugan, an assistant professor at UW-Madison’s Center for Limnology. “We got this really nice black ice so the conditions this even better for our experiment than the conditions last year.”
The study uses Trout Bog as a control lake for the study. There are no homes on the lake, and it’s been untouched except for where the researchers are collecting samples in the middle of the lake.
Dugan and her team will use the measurements as comparison to the ones they take at other snow-free lake.
The research assistants are each working on a different task to collect different kind of samples. The researchers take these and other samples multiple times throughout the winter at both Trout Bog and the one clear of snow.
“We’re trying to see influence that has on ice conditions and water chemistry and biology, thinking that if there’s no snow on a lake you’re going to get a lot of light penetrating through the ice and that light is going to let algae synthesize and have a lot of feedbacks to other parts of the system,” said Dugan.
Dugan says after one winter of data, they’re already seeing some differences on the snow-free lake.
“We saw that there was more algae, more both phytoplankton biomass and chlorophyl concentrations, so that supported that,” said Dugan. “If you increase the light, you’re going to get more algae production. We saw really high concentrations of methane. We’re still not sure if that relates to the plowing or now, so more measurements this winter to compare that too.”
Dugan noticed some physical changes to the ice as well.
“The other lake does have less white ice and more black ice so, so far the plowing is doing what we want it to do. I think the ice is actually a little thicker over at the other lake too,” Dugan said.
A lot of their findings so far support what they expected to happen. Dugan says one surprising thing was the lake temperature.
Most people would expect the snow-covered lake water temperature to be warmer because the snow acts as an insulator.
“What we found last year was that the lake that we cleared actually got a little bit warmer,” said Dugan. “Just a little bit so it’s hard to know yet if it’s just air temperature related or if clearing the snow actually allowed more sunlight into the lake so more energy warmed the water.”
This research gives some insight to what the future may hold for the Northwoods. The average Northwoods temperature in the winter is four degrees warmer than what it was 50 years ago.
If warming trends continue as expected, there could be less snow and less ice on lakes which would have more implications down the line.
“Temperature has such a huge influence on all life processes that warming a lake would definitely impact things like microbes and other cells that are trying to do their thing,” said Dugan.
Dugan and other researchers will continue to collect and process the data from this winter.
“From there we look at how the data matches up with our hypothesis on what we thought might happen and kind of compare the two years against each other, the two lakes against each try and understand how snow and ice are driving ecosystem processes,” said Dugan.
While figuring out the full extent of the impact of warming winters still requires more research, studies like this are key finding the answers.