An obscure but very interesting and important fact mentioned was the increased albedo effect from the larger ice in the Antarctic. Albedo, or reflective loss of solar radiation (by the ice) effectively cools the earth as the heat energy that would have been absorbed by open water is not absorbed to the same extent by ice, and is reflected into the atmosphere and into space. The loss of solar energy by albedo is limited by the insulating effect of the atmosphere, but the overall loss would be greater than the gain. net effect=cooling
Albedo works “against” the “We are melting all of the Arctic sea ice and will perish” syndrome so often propagandized.
First, ALL of the Arctic sea ice expends (freezes) and contracts (melts out again) like a “beanie cap” roughly centered on the north pole. Working out the arithmetic and geometry, you can pretty accurately summarize that “Arctic sea is at its maximum at latitude 71 north each year in early April, and is at its minimum at latitude 79-80 north each fall in mid-September.)
So it cycles between 71 north and 80 north.
Antarctic sea ice also expands and contracts: But much, much closer to the equator (at a LOWER altitude). Antarctic sea ice is at its minimum in late February at latitude 66 south, and expands until it reaches its maximum in mid-September at latitude 59-60 south!
Because the Antarctic sea is is closer tot he equator at all times of the year, it reflects much more sunlight than the Arctic sea ice does on an annual total basis. You have to play some mathematics to account for the changing solar output each day, the changing solar elevation angles, the changing tilt of the earth, the changing ice edge extents, etc ... but the Antarctic sea ice controls how much sunlight is reflected back into space 7 months of the year (September-March), and the smaller arctic sea ice only 5 months of the year (April-May-June-July-August).
Also, the Arctic sea ice tends to be 50% multi-year ice, so its gets dirtier and dust-covered. This reduces its albedo significantly during the summer: going from a clean & pristine 0.93 albedo to as low as 0.45 in June and July.
The Antarctic sea ice almost completely melts each Antarctic summer. So, each antarctic winter, spring and fall it is a fresh surface often covered with fresh snow and no industrial or “desert” dust. (No land area in the south, just the ice-covered high plateaus of Antarctica itself.)
So, any “excess” antarctic sea ice edge in September reflects over 5 times the energy that the same area of arctic sea ice would.