Beaufort Gyre
Friday, 1. May 2009, 09:55:23
In oceanography a ‘gyre’ is a circular pattern of currents in an ocean basin. The Gulf Stream is a part of the North Atlantic Subtropical Gyre. Here is a map of the five major ocean gyres.
This kind of world maps often irritates me. I think that everybody should own a globe to realise what our Earth really looks like - after all it is a sphere, and not flat. Some of you may have noticed that I often use polar-centered maps, to give you another look. Here is such a map of the Arctic Ocean - well I know that we usually talk about only three oceans: the Pacific Ocean, the Atlantic Ocean, and the Indian Ocean. Again this may partly be a consequence of the sort of world maps we use. It is more correct to talk about five oceans, the three I mentioned plus the Southern Ocean (around Antarctica) and finally the smallest of the five, the Arctic Ocean.
The Beaufort Gyre is an ocean and ice circulation pattern in the Beaufort Sea, north of Alaska. I have marked it with a B on the map. This gyre moves in a clockwise direction (looking from above the North Pole). This circulation results from an average high-pressure system that spawns winds over the region. Ice that forms in or drifts into the Beaufort Gyre has historically remained in the Arctic ice system for years, accumulating snow and thickening each winter. Beginning in the late 1990s, the ice began melting away while in the southern parts of the gyre, before completing the circulation.
Over the last few weeks I have started on several posts without finishing them (getting occupied with other thoughts and ideas). One of them was supposed to be about Ekman, maybe I’ll finish that one later. Anyway Vagn Ekman was a Swedish oceanographer. During the expedition of the Fram expedition (1893-1896), Fridtjof Nansen had observed that icebergs tend to drift not in the direction of the prevailing wind but at an angle of 20°-40° to the right. Bjerknes invited Ekman, still a student, to investigate the problem, which he did, and what made his name famous within oceanography. - Sorry, I am deflecting a bit.
The short story is that Beaufort gyre is a result of the Coriolis force, the prevailing winds, and what is know as Ekman transport (in short: movement of water at a certain angle to the wind).
Finally a map showing the relationship with other ocean currents in the Arctic area. The map is from the Arctic Monitoring and Assessment Programme (AMAP)
• http://nsidc.org/seaice/processes/circulation.html
• http://www.whoi.edu/beaufortgyre/index.html
• http://www.amap.no/
More about the Fram vessel and the Fram expedition:
• http://www.fram.museum.no/en/
This kind of world maps often irritates me. I think that everybody should own a globe to realise what our Earth really looks like - after all it is a sphere, and not flat. Some of you may have noticed that I often use polar-centered maps, to give you another look. Here is such a map of the Arctic Ocean - well I know that we usually talk about only three oceans: the Pacific Ocean, the Atlantic Ocean, and the Indian Ocean. Again this may partly be a consequence of the sort of world maps we use. It is more correct to talk about five oceans, the three I mentioned plus the Southern Ocean (around Antarctica) and finally the smallest of the five, the Arctic Ocean.
The Beaufort Gyre is an ocean and ice circulation pattern in the Beaufort Sea, north of Alaska. I have marked it with a B on the map. This gyre moves in a clockwise direction (looking from above the North Pole). This circulation results from an average high-pressure system that spawns winds over the region. Ice that forms in or drifts into the Beaufort Gyre has historically remained in the Arctic ice system for years, accumulating snow and thickening each winter. Beginning in the late 1990s, the ice began melting away while in the southern parts of the gyre, before completing the circulation.Over the last few weeks I have started on several posts without finishing them (getting occupied with other thoughts and ideas). One of them was supposed to be about Ekman, maybe I’ll finish that one later. Anyway Vagn Ekman was a Swedish oceanographer. During the expedition of the Fram expedition (1893-1896), Fridtjof Nansen had observed that icebergs tend to drift not in the direction of the prevailing wind but at an angle of 20°-40° to the right. Bjerknes invited Ekman, still a student, to investigate the problem, which he did, and what made his name famous within oceanography. - Sorry, I am deflecting a bit.
The short story is that Beaufort gyre is a result of the Coriolis force, the prevailing winds, and what is know as Ekman transport (in short: movement of water at a certain angle to the wind).
Finally a map showing the relationship with other ocean currents in the Arctic area. The map is from the Arctic Monitoring and Assessment Programme (AMAP)
• http://nsidc.org/seaice/processes/circulation.html
• http://www.whoi.edu/beaufortgyre/index.html
• http://www.amap.no/
More about the Fram vessel and the Fram expedition:
• http://www.fram.museum.no/en/
WIDGETIZE