Revisiting winter

Clean Wisconsin members got our quarterly publication The Defender delivered to their door at the start of this month; if that’s not you, the full PDF is available here now: http://cleanwisconsin.org/defender.

Below is the full version of a story we printed in our summer issue, discussing the impacts of the mild winter we had in Wisconsin this year — some of which we are still feeling in the throes of a hot, dry summer. Clean Wisconsin spoke with an assortment of experts around the state, and they gave their take on a few oddities that have been seen: More algae, dry soil, lower lake levels and more.

Most Wisconsinites can agree, the winter we had this year was unusually mild: And how fabulous that was. We could go out of doors in just a few layers and a sweater some days. With less snow, there was less salt on the roads and sidewalks that could dirty up our shoes. Plus, game days at Lambeau became all the more bearable for those in the stands.

This is all old news by now, but the truth is, we are still feeling the impacts of this winter’s weird weather. Although Wisconsinites saved on heating costs and salting the roads this winter, we’re paying for it elsewhere in a number of ways.

Firstly, milder weather during the winter months led to thinning of ice sheets over our lakes. We heard all about sunken vehicles and disappointed ice fishermen in the news, but it wasn’t until this spring that another problem was discovered: an explosion of algal blooms below the surface.

Emily Stanley, from the University of Wisconsin Center for Limnology, says the warm conditions this winter caused an influx of smelly, green algae that has become a problem all over the state. Although phosphorous runoff from point-source polluters is the main source of algae in our lakes, thin ice and a lack of snow coverage to block out sunlight gave the emerald-hued goo a major head start.

Stanley and her colleagues study the water chemistry and nutrients in Dane County’s Lake Mendota; what they found during a routine check-up on the lake in February took them by surprise.

“We discovered that, in fact, there was a ton of algae under the ice,” she said. “Because enough light could get through the ice to allow the algae to do its ‘photosynthesis thing,’ if you drilled a hole into the ice to measure its clarity, in February it was about the same as it is in the center of the lake now [in June].”

Furthermore, the algae growth led to a secondary change. Normally, Lake Mendota (and, presumably, lakes all around the state) will release a bit of carbon dioxide into the atmosphere each spring — but this year, it actually took a bit back. Why?

“Bacteria will be chewing up their food, and, like us, producing CO2. So, normally, CO2 will build up in the lake water, and when the ice melts in the spring there’s usually a big release,” Stanley said. “[Algae] takes in C02. With the algae being there this winter, CO2 did not build up under the ice like it normally does. And when the lakes warmed up, instead of belching out CO2, it actually—briefly, for a moment—pulled in CO2 from the atmosphere.”

Stanley emphasized that such an occurrence is neither good nor bad. While slightly less carbon in the atmosphere is somewhat of a benefit to the global environment, algae in our lakes is not desirable.

Algal blooms make our once-clear waters look like Kermit the Frog skin, cause rashes and breathing problems, and even killed two dogs last year.

Unfortunately, the warm weather we’re currently enjoying in Wisconsin (or, for those without AC, suffering through) also helps it grow particularly well. To help see things from a climate perspective, Associate Scientist at the UW Center for Climatic Research Michael Notaro explains how gradual changes in climate over the past decade have shown a number of noticeable effects.

“Northern Wisconsin, until recently, had a severe drought where the lakes actually got to Dust Bowl levels,” Notaro said. “[In Wisconsin], we should have more frequent days without precipitation, but on the days where it does rain … it just dumps these heavy downpours of rain. So [it is considered] drought conditions because there are more days without any rain.”

Here in Wisconsin, we have seen warm springs that come earlier in the last several decades. What that means is, birds migrate back to the state sooner and lakes melt a few weeks earlier than they had been in the 1950s. Plants and crops are also apt to bloom too soon and be killed by a sudden frost before summer sets in, Notaro explained.

“You can start to have cold air outbreaks, or just cold nights, which is normal in April, and when that happens it does damage to the plants,” he said, adding that drought later on in the year can be just as hazardous. “What we’re having this summer, with about a third of an inch [of rain] in the last month, the corn crops are really dry; the soil is really dry. The soil in my garden is hard as rock.”

By the end of this century, trends show that Wisconsin will actually continue to get wetter on the whole—but since temperatures will also increase, more evaporation will take place. This would cause our soil to dry out even more, and lower lake levels.

Withered leaves, a favorite spring that has ceased to bubble, or your local dock that stands higher above the water than it once did, are some of the first visible signs that changes are taking place in our environment.

Data from the Wisconsin Geological and Natural History Survey shows that, in places like Dane and Monroe counties, groundwater levels are historically low. Madeline Gotkowitz, a WGNHS hydrogeologist, says downward spikes in these levels can be attributed to lack of snowfall and snowmelt.

While low water levels do not necessarily mean that anyone’s well is going dry, many places in Wisconsin are well below normal as far as available groundwater resources. Gotkowitz said it is important to remember that just because water continues to flow out of the tap, doesn’t undermine the need to conserve water during drought conditions.

This winter we missed out on snowmen, sledding, ice fishing, and plenty of other things that make Wisconsin, well, Wisconsin. The summer so far continues to show some more interesting developments with which residents must cope. Being aware of changes in Wisconsin weather and climate helps us to better understand what is going on in other aspects of our state’s ecology year-round.

Written by Sarah Witman, communications intern

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