How are Antarctic seas below 0 degrees Celsius and not frozen?

Answer 1

This is possible because of the oceans high-salt-content, you may have heard before that if you mix salt into water it cools it down. The way this works is that when the NaCl(Salt) comes into contact with the H20(Water) there is a chemical reaction in which the two compounds bond, the energy required for the dissolving and bonding process is taken from the kinetic(or "movement") of the water molecules which slows them down and that which we call "Temperature" is simply the amount of energy inside an object at any given time. Thus having slowed down the water molecules the water is much colder, BUT, because the salt breaks the bonds between the ice crystals that would have normally appeared in such cold water the H20 remains a liquid. I hope you understood that.