It does make you wonder where all this is leading.

When you look at previous warm and cold climate regimes, you can see a
cycle. This cycle, however is not a constant and has progressively
shortened. I did some theoretical research a few years ago, regarding what
the climate may do just before the start of the next Ice Age. My conclusion
was: Climatic temperature trends would start to become unstable. Instead of
flipping from one regime to another at a constant pace, this pace would
start to quicken. Effectively, you would have shorter and shorter warm
periods and shorter and shorter cold periods. At some point in time, the
climate would SNAP ( if you like ) and a new constant would begin, i.e. the
start of an Ice Age. Obviously, if that is the case, then it's safe to
assume that we are not going to have an Ice Age just yet, or are we?. The
only fly in the ointment is CO2 induced global warming. Could this
artificial warming of the Earth, caused by a build-up of CO2 in the
atmosphere, cause a premature SNAP in the climate to a new constant?? That
is the only question I really have and I am not sure anyone has an answer!

Actual Previous Warm and Cold Climatic Periods:

975bc-250bc Subatlantic cold period ( lasted approx 725 years )
250bc-450ad Roman warm period ( lasted approx 700 years )
450ad-950ad Dark ages cold period ( lasted approx 500 years )
950ad-1400ad Medieval warm period ( lasted approx 450 years )
1400ad-1850ad Little Ice Age ( lasted approx 450 years )
1850ad-2003ad Modern warm period ( 153 years and counting... )

Notice how the durations of warm and cold periods are shortening, just as my
earlier theoretical work suggested.

Shaun Pudwell.


"Waghorn" wrote in message
...
Well contrary to popular belief, colder climate regimes are stormier
and
have wilder temperature swings, "Little Ice Age" of which 1779 was a
part of. Warmer climates regimes are generally less stormy, mainly
because
the temperature differential between the poles and the equator is
somewhat
less.
........About time this point was made because it has relevance to global
warming.
No doubt about the world being a considerably warmer place than it was
(whatever the cause) but why it should lead to greater storminess is not
obvious.
Dunno about the CET but a recent paper on SH trends -
Fyfe, John C., 2003: Extratropical Southern Hemisphere Cyclones:
Harbingers of Climate Change?. J.
Climate, 16 (17), 2802-2805.
In concert with a poleward shift in baroclinicity, the synoptic
environment south of 40°S appears to
have changed significantly over recent decades. South of 40°S and north of
the Antarctic Ocean the
number of cyclones has dramatically decreased, while over the Antarctic
Ocean a modest increase has
occurred. A global climate model with anthropogenic forcing produces
similar historical changes, and
under a "business-as-usual" emissions scenario predicts that the number of
sub-Antarctic Ocean
cyclones will drop by over 30% between now and century's end.

--
regards,
david
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