If water behaved like most substances, what would happen to lakes?

The behavior of water is unique due to its molecular structure and the hydrogen bonding that occurs between water molecules. Most substances contract and become denser as they cool, resulting in their solid form sinking to the bottom when they freeze. If water behaved like most substances, it would indeed freeze from the bottom up.

In this case, as the temperature drops, the water at the surface would cool first and solidify, forming ice that would sink. This would create a scenario where aquatic life would be impacted negatively because the ice layer on the surface would act as an insulating barrier, limiting the amount of oxygen dissolved at lower levels and potentially trapping heat. Furthermore, the bottom of lakes would remain liquid, which could lead to unpredictable conditions for organisms and overall ecosystem health.

Understanding this property of water is crucial, especially in the context of environmental science and ecology, as it helps explain why ice floats and why lakes and other bodies of water can support life even in freezing temperatures.