Here is a very good explanation for the increase in sea ice in the Antarctic:
Antarctic Sea Ice and Global Warming
quote:
there seem to be three things that can cause more of this ice. One might be the addition of fresh water to the system. That seems likely if the Antarctic glaciers are melting (which they are). Depending on where the fresh water goes, that could allow the formation of sea ice. Also, if precipitation increased in the area, that would add fresh water.
Second, the area where the sea ice is forming could be colder. That seems backwards in on a warming planet, but actually, that can happen too. Antarctica is, to a larger extent than the Arctic, a semi-closed system of air and sea currents, because it is a roundish continent surrounded by sea at one end of the planet. This means that cold air might be retained over the continent rather coherently. At the North Pole, “Winter (January) temperatures … can range from about −43 °C (−45 °F) to −26 °C (−15 °F), perhaps averaging around −34 °C (−29 °F),” while at the South Pole, “In winter, the average temperature remains steady at around −58 °C (−72 °F).” (source: Google). The north pole is sea, the south pole is land, and the south pole is at a higher elevation, but those differences are partly why the south pole is colder. Anyway, with all this cold air on the Southern Continent, perhaps one only needs to have air currents change a little to move that cold air over the sea a bit more to add to the chances of freezing water and making sea ice.
Third is the possibility that the disruptive effects of storms, waves, or surface currents could change, making for a calmer environment, allowing more ice formation.
Have any of these things happened?
Yes. Yes, they have.
Added cold seems to be a factor. Added fresh water seems to be a factor. Changes in where cold air and relatively fresh water goes seems to be a factor. I don’t know about storminess and currents at the outer edge of ice formation.
The dramatic and steady increase in Antarctic Sea Ice is yet another example of the effects of climate change.
(see article for data links)
Glacier ice melts during the summer, the fresh water from this stays near the surface where it is easier to freeze. Changing climate patterns cause colder air at the south pole in the winter, extending over the surrounding ocean, which causes more freezing.
Enjoy.