Madison lakes have an early “Spring Cleaning” – April 25, 2012
by Center for Limnology

If you head down to the shore of Lake Mendota, you’ll notice you can see right down to the bottom. In fact, the current Secchi reading is seven meters, meaning you can get a clear view of Lake Mendota’s depths more than 20 feet down.

At first glance, it might seem that there’s just not much going on down there, but Lake Mendota is actually teeming with life and right in the middle of an algae bloom.

So what gives on the clear water?

The secret to our currently crystal-clear lake is a tiny zooplankton called Daphnia pulicaria.

View full article

Deep freeze has yet to hit Madison lakes – December 27, 2011
by Chris Barncard

Wide swaths of lawn aren’t the only odd sight on campus this late in December.

There is still all kinds of open water on either side of Madison’s isthmus, as ice has yet to take hold on lakes Mendota or Monona.

That didn’t get odd in an official way until the last week, when the still-liquid lakes passed their average freeze-over dates. Lake Mendota is completely covered by ice by Dec. 20, on average, according to the Wisconsin State Climatology Office, affiliated with the Department of Atmospheric and Oceanic Sciences. Smaller Lake Monona is usually covered, on average, by Dec. 15.

“It’s Wisconsin,” says Stephen Carpenter, director of the UW–Madison Center for Limnology. “So expect the unexpected.”

View full article

Global grassroots lake science network has roots in Wisconsin – July 19, 2010
by David Tenenbaum

Inspired and led by freshwater scientists at the University of Wisconsin-Madison, researchers eager to understand global ecosystems from end to end are now monitoring a series of buoys in lakes on every continent except Africa. Each buoy carries instruments to measure fundamental data on the weather above the water and the temperature and chemistry below it.

The buoys are linked through GLEON — the Global Lake Ecological Observatory Network — but the motivation is mainly local, says UW-Madison limnologist Timothy Kratz, who chairs the network’s advisory board.

The network represents a grassroots approach to large-scale science, says Kratz. “We have these large, top-down initiatives, where all the instruments are as similar as possible, but this network is very much bottom-up. Each site already has its own local reasons for getting measurements. Banding together in the network makes the process more efficient, so we don’t repeat each other’s mistakes…”

View full article

Confronting toxic blue-green algae in Madison lakes – July 1, 2010

by David Tenenbaum

Harmful algal blooms, once considered mainly a problem in salt water, have been appearing with increasing severity in the Madison lakes, and a team of UW-Madison researchers has geared up to understand the when, where and why of these dangerous “blooms.”

No longer just a smelly, unsightly nuisance, the masses of blue-green algae can also exude toxins that attack the liver or nervous system.

One day, it may be possible to issue “algae forecasts” modeled on predictions of severe storms, says Katherina McMahon, a professor of civil engineering and bacteriology on campus. Eventually, she says, the results of research at UW-Madison could lead to a forecast: “Given the conditions today, we estimate an 85 percent chance of toxic blue-green algae tomorrow…”

View full article

From sky and lake, researchers study blue-green algae – April 2010

by Renee Meiller

It’s an unseasonably warm, early-April Friday afternoon in Madison, Wisconsin, and the calm day polishes the Lake Mendota surface to a sheen that’s just shy of glass.

A vintage flat-bottomed Boston whaler chugs slowly away from a dock adjacent to the famed University of Wisconsin-Madison Memorial Union Terrace. Soaking up the sun and expansive lake views, hundreds of Terrace-goers stare bemusedly at the whaler: Bobbing at the end of its tow rope is a 6-foot-tall, sunshine-yellow oceanographic buoy.

Its destination is the geographic center of Lake Mendota — essentially, the lake’s deepest point…

View full article