Lake temps/ ice in

[This'nThat]

Originally Posted by nj2nh

I am going to pass this along to my kids.nj2nh

NJ2NH, the 39 degree water temperature also explains why the whole lake doesn't freeze down to the bottom, and why the fish also don't freeze. The bottom layer of the lake ice is always in danger of being melted by the 39-degree temperature water underneath, which actually limits the thickness of the ice in our NH climate. Think about how much heat is in the massive body of water at a uniform 39 degrees! To put it in perpective, if you had a heat pump at your house, when the air temperature is 39 degrees outside, the heat pump can completely warm the entire house and keep it at a comfortable 68 degrees F inside -- that's a lot of heat at 39 degrees.

And of course, 39 degrees isn't freezing, so the fish are happy to be swimming in this relatively "warm" water -- given that they are a cold-blooded species and don't need to stay warm.