There are minor secondary physics effects from the future of the part of the Larsen C ice shelf that broke off on July 12, 2017. We briefly note them here, but expect earth system scientists will do full studies of them.
Of course, since the ice shelf was already floating, it did not raise sea levels when it detached, nor will it in the long run. When the landed glacier behind it melts, however, it will raise sea levels a dangerous and expensive 10 cm or 4 inches.
The new iceberg, called A-68, is 5,800 square-kilometers in area, or 2,200 square-miles. It is more than 200 meters or 700 feet thick, and weighs more than a trillion tons.
The secondary effect noted here is that we have had a large reflective mirror in A-68, which will eventually melt, and leave heat absorbing sea water in its place. The iceberg size has been compared in size to the state of Delaware, or the country of Luxembourg (no insults intended to either).
Since the shelf is at high latitude, it has low insolation, but near the poles the days are longer. While the yearly average insolation at the equator is 400 watts/m^2, at the poles it is 200 Watts/m^2.
As A-68 fulfills its destiny by moving more toward the equator as it breaks up, calves and melts, it’s reflection may increase in parts slightly, while it eventually drops to zero.
A much greater loss in reflectivity occurs in the declining Arctic sea ice, but it is again surrounding the North Pole.
