Describe how lakes are stratified during the summer.

Deep lakes are stratified during the summer and winter. In summer, the lake will have three different temperature zones. The epilimnion is the surface layer that is warmed by the sun. The thermocline is the middle layer that decreases 1^oC per meter of depth. The lowest layer is the hypolimnion and is cold water. The warmer, less dense water floats on top of the colder, more dense water.