-LRB-- NAO) This sea ice then melts in the Sub Polar Atlantic, releasing fresh water into the sub - polar Atlantic waters, which in turn impedes the formation
of NADW, which slows down the thermohaline
circulation causing warm
air not to be brought up from the lower latitudes as far north as previous while in lessening
amounts.
According to their modeling studies, the difference in the
amount of incoming solar radiation, in this case, primarily in the ultraviolet (UV) wavelengths, during the minima and maxima
of the 11 - yr solar cycle are large enough to produce a characteristic change in the winter
circulation pattern
of the atmosphere over North America... When the NAO is in its negative phase, more cold
air can seep south from the Arctic and impact the lower latitudes
of Europe and the eastern U.S., which helps spin up winter storm systems.