Liquid Water

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We have already seen water molecules freeze into ice on the surface of dust grains in space. We now meet an amazing thing about water. When they are as warm as the Earth, water molecules have enough movement energy to move around, sticking first to one partner and then to another. They form a liquid. As we will see, this movement is essential for life.
One odd thing about water is that liquid water takes up less space than ice, because as the molecules move past each other they are able to squash closer together. This is unusual. Most substances take up more space in liquid than solid form. The result of this is that water expands when it freezes, so that ice floats on top of liquid water. In most liquids the frozen part sinks to the bottom.

Question

What would happen to the oceans of the Earth in winter if water behaved like most liquids?