Question

Объясните почему вода в озере не замерзает полностью

Answer 1

Так как озеро покрыто льдом, то теплоотдача с поверхности воды не происходит.
Но если озеро мелкое и температура будет очень низкая до 40-50 градусов то оно может и замерзнуть до дна.

Answer 2

Why Does the Water in a Lake Not Completely Freeze?

The phenomenon of a lake not completely freezing is due to a combination of factors, including the density of water, the insulating properties of ice, and the movement of water.

Density of Water: Water is most dense at around 4 degrees Celsius. As the temperature of water decreases from 4 degrees Celsius to 0 degrees Celsius, it becomes less dense. This means that the colder water tends to stay near the surface, while the denser, slightly warmer water remains at the bottom. This stratification prevents the entire body of water from reaching the freezing point at the same time, allowing some water to remain in a liquid state even when the surface is frozen.

Insulating Properties of Ice: Once the surface of the lake freezes, the ice acts as an insulating layer. It prevents further heat loss from the water below, helping to maintain the liquid state of the water beneath the ice. This insulation effect is crucial in preventing the entire body of water from freezing.

Movement of Water: The movement of water, caused by wind or currents, also plays a role in preventing complete freezing. The movement disrupts the formation of ice, particularly in areas where the water is shallow or where there are inflows and outflows. This continuous movement can prevent the entire body of water from reaching the freezing point.

In summary, the density of water, the insulating properties of ice, and the movement of water all contribute to the phenomenon of a lake not completely freezing, allowing some water to remain in a liquid state even when the surface is frozen.