These articles explain lake concepts in layman's terms. Lake Associations are welcome to publish these articles in their newsletters and websites as long as they give RMBEL credit.

Spring Clarity

Was your lake water clarity lower than usual this May?  Many lakes in northern Minnesota experienced this.  It is most likely because of the late ice-out and/or the rainy last few weeks.

cloudywaterWhen the ice goes off the lake in the spring, the lake turns over (see article on lake stratification and mixing).  When the lake turns over, the water becomes cloudy and the nutrients that mix up from the bottom can feed algae blooms.  Usually spring turnover happens in late April or early May, but this year with the late ice out spring turnover occurred in late May.

In addition to the late ice out, we received 2-6 inches of rain in late May and early June.  This rain could have caused runoff and erosion, which can also make the lake cloudy.

This week, lake clarity should be very good because the lakes have started to stratify, and we’ve had a dry week.

Spring Turnover in our Lakes

We are now near to the summer season on our lakes again. This marks the fourth installment of my lake stratification (layers) and mixing articles. Once the ice melts off the lake, the lake goes through another period of mixing like it did back in the fall. [Read more…]

Water under the ice: winter layers and oxygen levels

We’ve actually had a real Minnesota winter this year, and we currently have a good thick ice cover. Today is the third installment of my articles about lake layers and mixing. We already talked about summer stratification and fall turnover; so what happens to the water under the ice in the winter? [Read more…]

Fall turnover in our lakes

Lake_layers_summerThe temperature has cooled lately and the wind has picked up. These are the ingredients needed for fall turnover in our lakes. A couple months ago I wrote about how the lakes separated into layers in the summer, which is called stratification. To recap, the layering of lakes has to do with the relationship between water density and temperature. [Read more…]

Right now, lakes are like layer cakes

Have you noticed lately while swimming that the surface water in the lake is very warm and deeper water is cooler? At this time in the summer, the lakes are separated into vertical layers like a cake; limnologists call this phenomenon stratification. Stratification is a major reason our Minnesota lakes behave the way they do. To understand lake stratification, we first must address the relationship between water density and temperature. Water is unique in that it is denser as a liquid than a solid; therefore, ice floats. If ice sank, our lakes would behave much differently in the winter! [Read more…]