Posted by Bo Qiu on November 13, 2000 at 14:27:28:
In Reply to: Bo Qui's results show that recirulation gyres are now a climate problem posted by Bill Johns on November 07, 2000 at 11:08:43:
Hello Bill,
Thank you for your very thoughtful comments. It is interesting
that you noted that the Latif-Barnett model does not resolve the
recirculation gyre dynamics. One point I didn't emphasize well
in the poster is that the anomalous geostrophic heat advection
(u Det T)' in the upper ocean heat balance is determined by
(u' Det T^bar), namely, the anomalous geostrophic flow advecting
the mean temperature. In other words, it is the large-scale KE
variability that is important, not the KE that brings in
anomalous warm/cold water masses. (This point is made in the
full paper of mine: JPO, 2000, 1486-1502.) This feature seems
to be the case in the Latif-Barnett scenario.
What determines the low-frequency oscillation in the
recirculation gyre is clearly the next question and
something I am hoping to address.
Thanks, Bo
: This poster makes a compelling argument that the
: subtropical recirculation gyres, at least in the Pacific, may
: be linked to decadal climate variability. So they are not
: just a dynamical curiosity any more. Though the poster
: mentions the Latif and Barnett (LB) mechanism for modulating the
: PDO, in fact the LB mechanism does not explicitly involve the
: inertial recirculation gyre.
: This leaves open the very interesting question of whether the
: recirculation gyre could amplify air sea interaction effect in the
: LB mechanism, if its changes in intensity are directly linked to
: changes in intensity of the broader subtropical gyre circulation.
: On the other hand, one can think of reasons why the recirculation
: gyre might vary independently of the large scale gyre spin up and
: spin down. An important question to answer.
: Bo is probably working on it already...