Why would life in a lake be affected if ice sank and lakes freeze from the bottom up?
Why would life in a lake be affected if ice sank and lakes freeze from the bottom up? If water instead froze from the bottom of a lake or river to the top, there would be profound ecological consequences. Shallow lakes would freeze solid; unless the plants, animals, and other organisms living there had some sort of adaptation that would keep their tissues from freezing, they would die.
How do fish breathe in a frozen lake?
“In most lakes there is enough oxygen under the ice that they survive the winter.” It's like having a bank account, he says: The fish gradually draw down their banked oxygen and hope there's enough to get through to spring. If not, some of them die.
How long can you stay in a frozen lake?
In water that is around the freezing point, a person is likely to survive only 15 to 45 minutes with flotation and possibly up to an hour or so with flotation and protective gear before the brain and heart stop (Table 1). The surface temperature of Lake Superior in early to mid-summer is about 40 to 50 F.
Do fish survive in frozen lakes?
Do fish die in frozen lakes or in lakes that are partially frozen? Since fish are cold-blooded animals, they can survive because they are able to regulate their body temperature to match their environment. However, they could die if a body of water freezes over completely and remains frozen for an extended period.
Where is the warmest water in a frozen lake?
As ice-over approaches and temperatures continue to cool, the lake's water column becomes stratified again, this time with the warmest water on the bottom and coldest water on the top.
How cold is the water at the bottom of a frozen lake?
Th e point of maximum densi ty of fresh wat er iS 39 2 F. This is about the temperature of the bottom of the lake when the surface freezes. The several strata lie in their order of density, decreasing gradually until within a few feet of the surface, when they suddenly fall to the freezing point adjoining the ice.
Why can life exist under frozen surfaces in lakes and ponds?
Water is less dense as a solid than as a liquid. This means that ice is less dense than liquid water, which is why it floats. This property is important, as it keeps ponds, lakes, and oceans from freezing solid and allows life to continue to thrive under the icy surface.