ESS200A
Prof. Jin-Yi Yu
Transient Eddies
qMid-latitude cyclone and anticyclone are the major transient eddies that play an important role in meridional transports of heat, momentum, and moisture.
qThese
mid-latitude weather systems grow from the
baroclinic instability associated with the
strong north-south temperature gradients in mid-latitudes.
qMid-latitude
cyclones have typical spatial scales of
wavenumbers 5-6 and have typical time scale
of 7-10 days.
qMid-latitude cyclones are marked by well-defined fronts separating the warm air mass from the south and the cold air mass from the north. (Very different from tropical hurricanes, which do not have frontal features).
(From Weather & Climate)