Although ice cover is affected by elements of climate such as temperature, it also drives changes in climate in several ways. First, ice sheets can be thousands of feet high, and may actually block or redirect air flow, perhaps causing warm air to deflect away from the area covered by the ice sheet, and preventing warming.
Ice sheets also affect sea level when they melt, disintegrate, or calve icebergs, all of which cause ice to enter the oceans. The image to the right shows the Larsen B Ice shelf in Antarctica, which was roughly the size of Rhode Island and broke up during the summer of 2002 because of warming caused by humans. Scientists believe that as the ice shelf began to warm and melt, the meltwater collected on the surface and then ran down into crevasses within the ice. As this water then repeatedly refroze and melted again, the crevasses expanded and eventually the structure of the ice sheet could not handle the stress and fell apart.
Ice sheets also affect sea level when they melt, disintegrate, or calve icebergs, all of which cause ice to enter the oceans. The image to the right shows the Larsen B Ice shelf in Antarctica, which was roughly the size of Rhode Island and broke up during the summer of 2002 because of warming caused by humans. Scientists believe that as the ice shelf began to warm and melt, the meltwater collected on the surface and then ran down into crevasses within the ice. As this water then repeatedly refroze and melted again, the crevasses expanded and eventually the structure of the ice sheet could not handle the stress and fell apart.
The Greenland and Antarctic ice sheets are the two largest ice sheets in the world, and hold 2.85 million km3 and 30 million km3 of ice, respectively. If the Greenland ice sheet were to melt entirely, which scientists believe is possible within the next several hundred years if global warming continues unchecked, it could raise global sea level by almost 24 feet. If the Antarctic ice sheet melted, global sea level would rise by 230 feet.
Another way in which ice sheets influence climate is through their reflectance. Because ice sheets are shiny, they can reflect incoming radiation back into space, unlike ice-free ground, which tends to absorb incoming solar energy.
Another way in which ice sheets influence climate is through their reflectance. Because ice sheets are shiny, they can reflect incoming radiation back into space, unlike ice-free ground, which tends to absorb incoming solar energy.