Adrian D. Shaw wrote:

Felly sgrifennodd Graham P Davis :
Although the NAD may be weaker, it hasn't shut off yet. Before our weather
is affected, it needs the ocean current system in the North Atlantic to
flip from the stable system we have now to the other stable system.

Did you mean "... to another stable system."? Because what you says
implies that there are only two possible stable states; it also sort of
implies that we know what the other stable state is. Can we trace this
through the records of ice cores, ocean sediment, tree rings or whatever?


From what I remember - and it was forty years ago I first read about it -
there are two stable systems for the currents in the North Atlantic. One is
the one we're used to, and the the other is the system I've described where
the Gulf Stream is a mostly closed system (at the surface) consisting of an
anticyclonic circulation and, to the north is the cyclonic, cold
circulation.

As far as I remember, the existence of these two types of circulation, and
the sudden changes from one to the other, was discovered from ice and
bottom sediment cores. I can't remember who the author of the book was, but
I believe he worked at Woods Hole Oceanographic Institute. Strange that one
of the scientists apparently claiming to have recently discovered the same
sudden circulation change works at the same institute. I suspect that it's
just lazy research work rather than plagiarism. I'd normally blame
mis-reporting by the media if I hadn't heard the same claim on various
programs.


--
Graham Davis
Bracknell