|MadSci Network: Earth Sciences|
Hello, Bhav! Ice has some unusual properties, the most important of which is that it floats. It is rather rare in nature that the solid of a substance (in this case, water) is less dense than the liquid phase. It is because ice floats that lakes, for example, do not freeze solid in the wintertime. Ice forms first, and tends to insulate the water below from further heat loss. Moreover, if ice did sink, the arctic and antarctic regions would be solid ice down the bottom of the ocean basin. This could have a considerable effect on the deep ocean currents, and all sorts of effects on the climate.
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