North Atlantic Oscillation
qThe NAO is the dominant mode of winter climate variability in the North Atlantic region ranging from central North America to Europe and much into Northern Asia.
q
qThe NAO is
a large scale seesaw in
atmospheric mass between
the subtropical high and the
polar low.
q
qThe
corresponding index varies from year
to year, but also exhibits a
tendency to remain in one phase
for intervals lasting several
years.
(from http://www.ldeo.columbia.edu/res/pi/NAO/)