Essential Terms Associated With Ice


Ice is the solid form of water, formed by freezing, the compaction of snow and the condensation of water vapour directly into crystals. The density of the ice is 0.9166, that is less than water, and thus Ice floats.
Ice Age- A geological period of widespread glacial activity, when Ice sheets covered large parts of the continents is called Ice Age.
Ice Barrier- The edge of the Ancient ice sheet is called ice barrier, for example, the Ross Ice Barrier.
Ice Blink- The glare from the underside of a cloud layer, produced by the reflection from an ice surface below, as in the case of an ice sheet or of pack ice, is called ice blink. This may produce eye irritation and even snow blindness.
Ice Cap- A permanent mass of ice covering plateaus and high latitude islands, but smaller than an ice sheet; for example Spitsbergen; Novaya Zemlya; Franz Josef Land
Ice Dam- A dam on river caused by clocks of ice, which may result in widespread flooding in spring and early summer, is called ice dam, as along the Siberian and Canadian rivers (also called Ice Jam)
Ice Edge-The boundary between open water and a mass of floating sea ice.
Ice- Field- The term refers to a large continuous area of Packice or sea ice by both USA and Britain definition. Generally it is used much more widely; for example, the Columbia Ice field in Jasper National Park, Alberta, Canada which is 130 square miles in area.
Ice Fall- A confused labyrinth of deep clefts and ice pinnacles formed by the intersection of ‘crevasses’ where a glacier steepens, is called Ice fall, for example, the glaciers moving down from the flanks of Mont Blank to the Chamonix valley, descending over 6000 feet in only 2 miles. The huge Khumbu ice fall was a major obstacle in the approach of dimbers to the South Col. Of Everest.
Ice Floe- a thin, detached, floating horizontal sheet of sea ice is called Floe; hence Ice Floe.
Ice Fog- A fog consisting of minute ice crystals suspended in the air, in conditions of calm air and low temperatures, is called Ice fog.
Ice Front- A cliff of ice, the seaward face of a floating mass of ice, such as an ice shelf or tidal glacier, is called an Ice Front.
Ice Jam- A mass of broken ice fragments, especially during spring melting jammed in a narrow channel, causing flooding is called Ice Jam.
Icelandic Low- The mean sub polar atmospheric low pressure area in the North Atlantic Ocean between Iceland and Greenland, most marked in winter, it is not a very intense, stationary ‘low’, but an area of rapidly moving individual ‘lows’, interrupted by occasional periods of higher pressure.
Ice Shelf-A large floating ice sheet attached to the coastline is called an Ice Shelf for example, the Ross Ice Shelf.

Essential Terms Associated With Snow


The type of precipitation formed when water vapour condenses at a temperature below freezing point, so passing directly from the gaseous to the solid stage, and forming minute spicules of ice. These unite into crystals which are either ‘flat hexagonal plates’ or ‘hexagonal prisms’, revealing infinite variations in their patterns. These crystals aggregate into Snow Flakes, where the lower atmosphere is sufficiently cool, they will reach the ground without melting. Snow may be dry and powdery under low temperature conditions, as in Antarctica.
Snow Avalanche- A fall of snow down a hill side is called Snow Avalanche. It may be-
1.      Wind Slab- where the snow is crusted and compacted.
2.      A dry Snow Avalanche- usually of new snow in winter and
3.      A Wet Snow Avalanche- caused by a sudden spring thaw.
Snow Drift- A bank of snow drifted by the wind which has accumulated against obstacles, sometimes to great depths; this may block roads and railway lines, unless protected by barriers, sheds or snow drift fences.
Snow Field- An area of permanent snow which has accumulated in a basin shaped hollow among the mountains or on a plateau; for example, the Ewig Schneefeld near the Jungrau in the Bernese Oberland.
Snow Line- The lowest edge of a more or less continuous snow cover is called a snow line.
The Permanent Snow Line- is the level at which wastage of snow by melting in summer fails to remove winter accumulation. This varies with latitude, altitude and aspect. At the poles it lies at sea level, in south Greenland at 2000 feet, in Norway at 4 to 5000 feet, in the Alps about 9000 feet, in Eastern Africa at 16000 feet.
The Winter Snow Line-fluctuates from year to year, but is markedly lower than the permanent snowline. There is no permanent snow line in Great Britain, though in winter in the Highlands of Scotland snowline lies above 3000 feet for about 80 days.