Fishes survive in ponds even when the atmospheric temperature is below zero degree celsius, why ?

Explain the following……

1-Fishes survive in ponds even when the atmospheric temperature is below 0⁰ C.

Ans-When the temperature of atmosphere falls below 0⁰ C, water on the surface loses heat to the atmosphere and gradually freezes into ice, but water below the ice layer remains at 4⁰ C. The  water layer just below the ice in contact with it will be at 0⁰ C. Thus, temperature of water in contact with ice is 0⁰ C, while the temperature of water layers below the ice gradually increases to 4⁰ C. As a result, fish and other aquatic creatures remain alive in water of pond (or lake), though water on the surface has frozen into ice.

ANOMALOUS EXPANSION OF WATER:

If we take some water at 0⁰ C and start heating it, we find that it contracts in the temperature range from 0^o C to 4^o C. On heating it further above 4^o C, it expand . Similarly, it water initially at a temperature above 4^o C is cooled , it contracts till the temperature of water reaches 4^o  C. On further cooling it below 4^o C to 0^o C, its expands. This unusual expansion of water on cooling it in the temperature range 4^o C to 0⁰ C is called anomalous expansion of water.

Related Question:

1- Do pipes burst in cold weather?

2-How cold does it have to be for pipes to freeze and burst?

3-What causes water pipes to burst?

4-In winter , water tank (or ocean) starts freezing from the surface and not from the bottom.?

4-In winter , water tank (or ocean) starts freezing from the surface and not from the bottom.?

6-A hollow glass sphere which floats with its entire volume submerge in water at 4⁰ C sinks when water is heated above 4⁰ C?

7- A glass bottle completely filled with water and tightly closed at room temperature, is likely to burst when kept in the freezer of a refrigerator?

Here the link you can see the Answer:

https://knowledgecraker.blogspot.com/2020/06/explain-following-water-pipes-in-cooler.html