The quadrants are divided counter-clockwise in the following manner:Ĭ = 180-90E (Western Ross Sea/Wilkesland) Iceberg names are derived from the Antarctic quadrant in which they were originally sighted. Due to the work of the USNIC, scientists are able to learn more about climate and ocean processes and ships traversing the Antarctic waters are informed of any icebergs which might pose a danger along their journey. This information is invaluable for scientists who study icebergs. They provide global ice analyses and forecasts, and more than 95% of the data used in its sea ice analyses are derived from the remote sensors on polar-orbiting satellites. National Ice Center (USNIC), which is the only organization that names and tracks all Antarctic icebergs larger than 1650 meters (5,400 square feet).
Icebergs are monitored worldwide by the U.S.
The icy waters surrounding Antarctica are home to a vast majority of the icebergs that navigate Earth’s oceans. They are often transparent but can appear green or black in color. Growlers are smaller fragments of ice that extend less than 1meter (three feet) above the sea surface and measure about the size of a grand piano. Its height is generally greater than three feet, but less than 5 meters (16 feet) above sea level. A bergy bit is a medium-to-large fragment of ice about the size of a small house. Bergy bits and growlers can originate from glaciers or shelf ice, and may also be the result of a large iceberg that has broken up. Smaller pieces of floating ice are known as bergy bits and growlers. It differs from tabular icebergs in that its shape resembles more a block rather than a flat sheet of ice.īlocky iceberg (left), Pinnacle iceberg (center) and a Wedge iceberg (right) in the Ross Sea © Toine Hendriks - Oceanwide Expeditions Blocky: An iceberg with steep, vertical sides and a flat top.Dry-dock: An iceberg that has eroded to form a little U-shaped harbor-like enclosure.Wedge: An iceberg with a steep edge on one side and a slope on the opposite side, the top is shaped into a pyramid-like tip.Pinnacle: An iceberg with one or more spires.Dome: An iceberg with, of course, a rounded top.The following are some common types of icebergs and the names used to describe them in iceberg observation. Non-tabular icebergs have different shapes. Tabular iceberg in the Ross Sea © Rolf Stange - Oceanwide Expeditions Non-tabular icebergs This type of iceberg can be quite large, and it can sometimes be referred to as an ice island, such as in the case of the Pobeda Ice Island. Tabular icebergs have steep sides and a flat top, much like a plateau. Typically, they are divided into two main categories, tabular and non-tabular icebergs. But in reality, any chunk of ice larger than 5 meters (16 feet) across and at least 30 meters (98 feet) thick can be called an iceberg - and they come in various sizes and shapes to boot. When one imagines icebergs, the first image that usually comes to mind is that of an immense spiky iceberg, majestically floating in the freezing waters. Icebergs near Cape Evans, Ross Sea © Rolf Stange - Oceanwide Expeditions Types of icebergs So that you may appropriately ready yourself for that joyous moment, in this article you will find everything you need to know about Antarctic icebergs. Regardless, the sighting of the first iceberg is always a moment to celebrate in any and all Antarctic expeditions. This fact is actually what gave rise to the nowadays popular phrase “the tip of the iceberg”. They float freely along with the Antarctic currents, with about 90 per cent of their mass below the surface of the water. Pieces of ice are continuously breaking off from ice shelf, glaciers or other icebergs. The ice in Antarctica might seem static, but it is constantly moving. This paper reports a glacier slip law based on rate-and-state friction, evidenced by laboratory observations.Everything you need to know about Antarctic icebergs A slip law for glaciers on deformable beds. An article presenting how icequakes are useful for studying glacier stick–slip behaviour. Changing friction at the base of an Alpine glacier. A report reviewing the key areas of uncertainty in current sea-level-rise projections. in IPCC Special Report on the Ocean and Cryosphere in a Changing Climate (eds Pörtner, H.-O. This paper reports how glacier slip is poorly constrained in numerical ice dynamics models. Potential sea-level rise from Antarctic ice-sheet instability constrained by observations. An article that highlights the importance of glacier slip for moving ice off the continent and into the oceans.
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