What is the difference between sea ice and land ice?
Sea ice, as in Arctic ice cap, consists of salt water on the surface of the ocean, which has been frozen. Land ice such as glaciers, ice caps and ice sheets, which are immense glaciers, consist of fresh water from precipitation.
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00:00Sea ice, as in the Arctic, consists of salt water on the surface of the ocean which has
00:14been frozen.
00:17When temperatures rise in summer, it melts, or partially melts, before refreezing the
00:21following winter.
00:23Just like an ice block melting in a glass of water, the melting of sea ice does not
00:27raise sea levels.
00:28But the reduction of sea ice does amplify the heating of the oceans, as the darker
00:32water absorbs more sunlight than the more reflective ice, an effect known as albedo.
00:38Land ice, such as glaciers, ice caps and ice sheets, which are immense glaciers, consists
00:44of fresh water from precipitation, sometimes kilometers thick.
00:48These glacial ice formations flow towards the sea, pushed by the weight of their ice.
00:53They can extend into the ocean, forming ice shelves.
00:56There are two ice sheets on Earth, in Antarctica and Greenland, with the smaller ice caps found
01:02elsewhere such as Iceland.
01:04Due to the effect of heat, these ice shelves become thinner until they break off and become
01:09icebergs, a process known as carving.
01:12In this case of glacial ice, water is transferred from the land to the oceans, which does raise
01:18sea levels.
01:19Ice shelves can also act to retain the ice sheet, or glacier, and slow its movement.
01:23If the shelves are sufficiently weakened, the movement of the ice sheet will increase,
01:28releasing even more fresh water into the oceans.
01:31According to the scientific group known as the IPCC, just the melting of the Antarctic
01:36ice sheet would raise sea levels by 10 to 30 centimeters by the end of the century.