jäämägesid

Jäämägesid, often translated as icebergs, are large pieces of freshwater ice that have broken off from glaciers or ice shelves and are floating freely in open water. The vast majority of an iceberg's mass, typically around 90%, is submerged beneath the surface, making them a significant hazard to shipping. Only about 10% of an iceberg is visible above the water, a phenomenon commonly referred to as the "tip of the iceberg."

Icebergs originate from land-based ice formations, primarily in polar regions like Antarctica and Greenland. As glaciers or ice shelves advance towards the sea, the immense pressure and tidal forces can cause large sections to calve, or break off. These calved pieces then become icebergs, carried by ocean currents.

The size of icebergs can vary dramatically, from small fragments to colossal masses measuring kilometers in length and hundreds of meters in height. Their shapes are also diverse, influenced by the melting process, collisions with other ice, and the way they originally broke off. Common shapes include tabular icebergs, which are flat-topped and resemble floating mesas, and irregular or dry-docked icebergs, which have more complex and often dramatic forms.

The melting of icebergs contributes to the salinity and temperature of ocean waters. As they melt, they release freshwater, which can locally affect marine ecosystems. Their journey from polar regions to warmer waters is often long, and they eventually melt completely, returning their water to the ocean.