An area containing a low atmospheric pressure system which remains between Greenland and Iceland. IL behavior is directly affected by the North Atlantic Oscillation (NAO). A positive NAO means that there is more pressure on the IL. This increase in pressure of the IL causes a greater amount of cold winds to be compressed in the area; this area is colder than usual and those areas farthest from it are warmer than usual. On the other hand, a negative NAO means that there is less pressure on the IL. Pressure decrease of the IL allows the cold winds to spread further south.