Fram Strait
Encyclopedia
The Fram Strait is a passage from the Arctic Ocean
to the Greenland Sea
and Norwegian Sea
, between Greenland
and Spitsbergen
. It is named after the Norwegian
ship Fram
. The Fram Strait is the major connection between the Arctic Ocean
and the world ocean
.
the Arctic ice pack has been diminishing in size and thickness. Most of the ice pack appears over the winter, freezing up to 1 m deep, but then melts back to open water by August. The area covered by multi-year ice, however, is thought to have remained relatively stable, an equilibrium between creation (first-year ice that persists into its second winter, becoming multi-year ice) and destruction (flow of sea ice through the Fram Strait and southward along the eastern coast of Greenland). Approximately 90% of sea ice exported from the Arctic is transported by the Eastern Greenland Current
, joining the current as it passes through the Fram Strait.
The amount of sea ice passing through the Fram Strait varies from year to year, as seen in this animation.
As the icepack size diminishes, the speed at which it diminishes is thought to accelerate summer melting of multi-year ice because of a positive feedback loop: open water is less reflective than sea ice, absorbing heat that ice reflects. Transport of sea ice through the Fram Strait affects the global climate through its influence on the thermohaline circulation
. This is because sea ice essentially corresponds to fresh water; its salt content is about 4 parts per thousand compared to about 35 parts per thousand for sea water.
Based upon computer modelling, it is believed that 60 to 70% of the fluctuation in the quantity of sea ice flowing through the Fram Strait is correlated with a fluctuation with period 6–7 years in which the Icelandic Low Pressure system
extends eastward into the Barents Sea
.
In the past century, the sea surface temperature
at Fram Strait has on average warmed roughly 1.9°C (3.5°F), and is 1.4°C (2.5°F) warmer than during the Medieval Warm Period
. The warming in this area has likely amplified Arctic shrinkage
, and serves as a positive feedback
mechanism for transporting more heat to the Arctic.
Arctic Ocean
The Arctic Ocean, located in the Northern Hemisphere and mostly in the Arctic north polar region, is the smallest and shallowest of the world's five major oceanic divisions...
to the Greenland Sea
Greenland Sea
The Greenland Sea is a body of water that borders Greenland to the west, the Svalbard archipelago to the east, Fram Strait and the Arctic Ocean to the north, and the Norwegian Sea and Iceland to the south. The Greenland Sea is often defined as part of the Arctic Ocean, sometimes as part of the...
and Norwegian Sea
Norwegian Sea
The Norwegian Sea is a marginal sea in the North Atlantic Ocean, northwest of Norway. It is located between the North Sea and the Greenland Sea and adjoins the North Atlantic Ocean to the west and the Barents Sea to the northeast. In the southwest, it is separated from the Atlantic Ocean by a...
, between Greenland
Greenland
Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...
and Spitsbergen
Spitsbergen
Spitsbergen is the largest and only permanently populated island of the Svalbard archipelago in Norway. Constituting the western-most bulk of the archipelago, it borders the Arctic Ocean, the Norwegian Sea and the Greenland Sea...
. It is named after the Norwegian
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
ship Fram
Fram
Fram is a ship that was used in expeditions of the Arctic and Antarctic regions by the Norwegian explorers Fridtjof Nansen, Otto Sverdrup, Oscar Wisting, and Roald Amundsen between 1893 and 1912...
. The Fram Strait is the major connection between the Arctic Ocean
Arctic Ocean
The Arctic Ocean, located in the Northern Hemisphere and mostly in the Arctic north polar region, is the smallest and shallowest of the world's five major oceanic divisions...
and the world ocean
World Ocean
The World Ocean, world ocean, or global ocean, is the interconnected system of the Earth's oceanic waters, and comprises the bulk of the hydrosphere, covering almost 71% of the Earth's surface, with a total volume of 1.332 billion cubic kilometres.The unity and continuity of the World Ocean, with...
.
Role in Arctic Sea ice
The Fram strait plays a central role in whether the north ice cap will survive future summers. With global warmingGlobal warming
Global warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...
the Arctic ice pack has been diminishing in size and thickness. Most of the ice pack appears over the winter, freezing up to 1 m deep, but then melts back to open water by August. The area covered by multi-year ice, however, is thought to have remained relatively stable, an equilibrium between creation (first-year ice that persists into its second winter, becoming multi-year ice) and destruction (flow of sea ice through the Fram Strait and southward along the eastern coast of Greenland). Approximately 90% of sea ice exported from the Arctic is transported by the Eastern Greenland Current
East Greenland Current
The East Greenland Current is a cold, low salinity current that extends from Fram Strait to Cape Farewell . The current is located off the eastern coast of Greenland along the Greenland continental margin. The current cuts through the Nordic Seas and through the Denmark Strait...
, joining the current as it passes through the Fram Strait.
The amount of sea ice passing through the Fram Strait varies from year to year, as seen in this animation.
As the icepack size diminishes, the speed at which it diminishes is thought to accelerate summer melting of multi-year ice because of a positive feedback loop: open water is less reflective than sea ice, absorbing heat that ice reflects. Transport of sea ice through the Fram Strait affects the global climate through its influence on the thermohaline circulation
Thermohaline circulation
The term thermohaline circulation refers to a part of the large-scale ocean circulation that is driven by global density gradients created by surface heat and freshwater fluxes....
. This is because sea ice essentially corresponds to fresh water; its salt content is about 4 parts per thousand compared to about 35 parts per thousand for sea water.
Based upon computer modelling, it is believed that 60 to 70% of the fluctuation in the quantity of sea ice flowing through the Fram Strait is correlated with a fluctuation with period 6–7 years in which the Icelandic Low Pressure system
Icelandic Low
The Icelandic Low is a semi-permanent centre of low atmospheric pressure found between Iceland and southern Greenland and extending in the Northern Hemisphere winter into the Barents Sea. In summer it weakens and splits into two centres, one near Davis Strait and the other west of Iceland...
extends eastward into the Barents Sea
Barents Sea
The Barents Sea is a marginal sea of the Arctic Ocean, located north of Norway and Russia. Known in the Middle Ages as the Murman Sea, the sea takes its current name from the Dutch navigator Willem Barents...
.
In the past century, the sea surface temperature
Sea surface temperature
Sea surface temperature is the water temperature close to the oceans surface. The exact meaning of surface varies according to the measurement method used, but it is between and below the sea surface. Air masses in the Earth's atmosphere are highly modified by sea surface temperatures within a...
at Fram Strait has on average warmed roughly 1.9°C (3.5°F), and is 1.4°C (2.5°F) warmer than during the Medieval Warm Period
Medieval Warm Period
The Medieval Warm Period , Medieval Climate Optimum, or Medieval Climatic Anomaly was a time of warm climate in the North Atlantic region, that may also have been related to other climate events around the world during that time, including in China, New Zealand, and other countries lasting from...
. The warming in this area has likely amplified Arctic shrinkage
Arctic shrinkage
Ongoing changes in the climate of the Arctic include rising temperatures, loss of sea ice, and melting of the Greenland ice sheet. Projections of sea ice loss suggest that the Arctic ocean will likely be free of summer sea ice sometime between 2060 and 2080, while another estimate puts this date at...
, and serves as a positive feedback
Positive feedback
Positive feedback is a process in which the effects of a small disturbance on a system include an increase in the magnitude of the perturbation. That is, A produces more of B which in turn produces more of A. In contrast, a system that responds to a perturbation in a way that reduces its effect is...
mechanism for transporting more heat to the Arctic.
External links
- Daily Satellite Picture