John Hall wrote:

In article ,
Peter Hayes writes:
Keith (Southend) wrote:

Peter Hayes wrote:


How much does the Gulf Stream contribute to warming the UK compared to
our traditional warm and moist south westerlies?


Surely the two go hand in hand.

Would we lose these warm and moist south westerlies if the Gulf Stream
stopped?

No, but they would be less warm and perhaps less prevalent.

My guess is that the change in sea temperature pattern would produce a
virtually permanent change to a strongly positive NAO, with strong,
cyclonic westerlies prevailing over the UK. This is assuming the SST
anomaly work by Lamb and others in the 60s still applied.

In Summer, in spite of increased cyclonicity, it is likely that the weather
would be drier than it is now - due to the reduced amount of moisture
picked up from the cold sea to the west of the UK - dull, except to the lee
of high ground where there would be breaks in the Sc sheet, and cool.

In Winter, the weather pattern should prevail but the cold ocean would still
be warm enough to add moisture to the cold air sweeping eastwards into the
Atlantic from Canada. This means that we could see cold winters with snow
showers affecting west-facing coasts. Longer periods of snow could be
associated with frontal waves running across, or to the south of the
country or *maybe* polar lows running eastwards across the Atlantic.

One further thought. If this change in circulation comes about, what will be
the effect on the Arctic? The change in circulation will not only cut off
the supply of warm water from the Gulf Stream source, the water returning
to the Arctic from the returning Labrador and East Greenland currents will
not only be colder but less saline. How will that impact ice cover in the
Arctic? Could there be a cooling of the Arctic, reduced melting of the
Greenland ice and, consequently, a switching back on of the NAD?


--
Graham Davis
Bracknell