Twenty years after its launch, the network that taught Americans about isobars and Icelandic lows is a cable TV staple and a big moneymaker.
12.
The band are named after the North Atlantic Oscillation, a fluctuating change in the atmospheric pressure differential that exists between the Icelandic Low and Azores High.
13.
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.
14.
A permanent low-pressure system over Iceland ( the Icelandic Low ) and a permanent high-pressure system over the Azores ( the Azores High ) control the direction and strength of westerly winds into Europe.
15.
By the end of September temperatures are already falling to near freezing and October sees the beginning of the long winter and a return to heavy snow drive by the western side of the Icelandic Low.
16.
During the winter, when the index is high ( NAO + ), the Icelandic low draws a stronger south-westerly circulation over the eastern half of the North American continent which prevents Arctic air from plunging southward.
17.
Labrador, in eastern Canada, is similarly wet throughout the year due to the semi-permanent Icelandic Low and can receive up to of rainfall equivalent per year, creating a snow cover of up to that does not melt until June.
