The term shelf ice describes a floating mass of ice attached to a coastline. The spelling of shelf ice is straightforward: /ʃɛlf/ for the base word shelf, and /aɪs/ for ice. The phonetic representation highlights the 'sh' sound created when pronouncing the 's' and 'h' sounds in sequence in shelf. The 'i' in ice produces a long 'a' sound, while the 's' blends with the following vowel to create an 's' sound. Overall, the correct pronunciation of shelf ice is /ʃɛlf aɪs/.
Shelf ice, also commonly referred to as an ice shelf, is a large, floating mass of ice that extends out over the ocean from a landmass or a glacier. It forms when glaciers or ice sheets flow into the ocean, and the frozen ice continues to advance and push outwards until it reaches a point where it begins to float on the water's surface. This floating ice shelf typically remains connected to the land or glacier through the process of calving, in which large chunks or icebergs break off and detach from the main ice mass.
Shelf ice is distinct from sea ice, which forms directly from the freezing of seawater. It is composed of compacted snowfall over many years, forming a thick layer of ice that can extend for several kilometers. The thickness of shelf ice can vary greatly, with some reaching hundreds of meters in thickness.
These massive ice shelves not only contribute to the overall stability of glaciers and ice sheets but also act as a buffer, inhibiting the direct interaction between the ocean and the land ice. Shelf ice acts as a barrier to reduce the rate at which glaciers and ice sheets melt and contribute to sea-level rise. However, due to climate change and rising temperatures, shelf ice is increasingly vulnerable to melting and disintegration, leading to the release of immense volumes of ice into the ocean and subsequent sea-level rise. The collapse of major shelf ice formations, such as those in Antarctica, can have significant global consequences on ocean currents, ecosystems, and coastal areas.
The etymology of the word "shelf ice" can be traced back to its individual components.
The word "shelf" comes from the Old English word "sceald", meaning "ledge" or "shelf". The term was also influenced by the Old English word "scylfe", which meant "projection" or "shelf".
The word "ice" derived from the Old English word "īs", which can be traced back to the Proto-Germanic word "īsaz". This term is related to the Old Norse word "ís" and the Dutch word "ijs", all of which signify "ice".
When these two components are combined, "shelf ice" refers to a mass of ice that forms along the edge of a body of water, such as a lake or sea, typically projecting outwards like a ledge or shelf.