Excellent link, thanks! Here are some key points for convenience (although the article's so short that this is practically half of it): > the rate of rotation

Excellent link, thanks! Here are some key points for convenience (although the article's so short that this is practically half of it): > the rate of rotation varies by up to a millisecond per day [regardless of ice melting] > Melting land ice ... will change the Earth’s rotation only if the meltwater flows into the oceans > For example, if the Greenland ice sheet were to completely melt and the meltwater were to completely flow into the oceans, then ... the length of the day [would become] longer ... by about two milliseconds > Melting sea ice, such as the Arctic ice cap, does not change sea level because the ice displaces its volume and, hence, does not change the Earth’s rotation.