Jääkerrokset

Jääkerrokset, also known as ice sheets, are vast, permanent expanses of ice that cover large areas of land. They are characterized by their immense thickness, often exceeding kilometers, and their slow, creeping movement under their own weight. The two largest ice sheets on Earth today are the Antarctic ice sheet and the Greenland ice sheet. These massive bodies of ice play a significant role in global climate and sea levels.

The formation of ice sheets is a long-term process that occurs in regions where snowfall accumulates faster than it melts over thousands of years. As snow is buried under subsequent layers, it compresses and transforms into firn, and eventually into dense glacial ice. The weight of the overlying ice forces it to flow outwards from the center of accumulation, a process driven by gravity.

Jääkerrokset are crucial components of the Earth's cryosphere. They store a significant portion of the planet's freshwater and influence global ocean circulation patterns through the formation of dense, cold water that sinks in polar regions. Changes in the size and mass of ice sheets, particularly due to rising global temperatures, have profound implications for sea-level rise, posing a threat to coastal communities worldwide. Scientists monitor these ice sheets closely to understand their dynamics and predict future changes.