Greenland and Antarctica are home to most of the world's glacial ice – including its only two ice sheets – making them areas of particular interest to scientists.
When an ice cube is exposed to a heat source, like warm water or air, it melts. So, it's no surprise that a warming climate is causing our glaciers and ice sheets to melt. However, predicting just how much the glaciers and ice sheets will melt and how quickly – key components of sea level rise – is not nearly as straightforward.
Glaciers and ice sheets are far more complex structures than ice cubes. They form when snow accumulates and is compressed into ice by new snow over many years. As they grow, they begin to move slowly under the pressure of their own weight, dragging smaller rocks and debris across the land with them. Glacial ice that extends to cover large landmasses, as it does in Antarctica and Greenland, is considered an ice sheet.
The processes that cause glaciers and ice sheets to lose mass are also more complex. An ice cube's surface melts when it's exposed to ambient (warm) air. And while warm air certainly melts the surface of glaciers and ice sheets, they're also significantly affected by other factors including the ocean water that surrounds them, the terrain (both land and ocean) over which they move, and even their own meltwater.
Continue reading at NASA Earth Sciences Division
Image via NASA Earth Sciences Division
