UK temps,SSTs,NAO etc
"Pete B" wrote in message
news:40237f95$0$916$9b0f33e3@clyde...
"Waghorn" wrote in message
...
Another recent paper from the Journal of Climate of interest-
Qian, Budong, and Mark A. Saunders, 2003: Summer U.K. Temperature and
Its
Links to Preceding
Eurasian Snow Cover, North Atlantic SSTs, and the NAO. J. Climate, 16
(24), 4108-4120.
Motivated by an attempt to predict summer (June-August) U.K.
temperatures,
the time-lagged
correlations between summer U.K. and European temperatures and prior
snow
cover, North Atlantic sea
surface temperatures (SSTs), and the North Atlantic Oscillation (NAO)
are
examined. The analysis
centers on the 30-yr period 1972-2001 corresponding to the interval of
reliable satellite-derived
land snow cover data. A significant association is found between late
winter Eurasian snow cover and
upcoming summer temperatures over the British Isles and adjacent areas,
this link being strongest
with January-March snow cover. Significant links are also observed
between
summer temperatures and
the preceding late winter NAO index and with a leading principal
component
of North Atlantic SST
variability. The physical mechanisms underlying these time-lagged
correlations are investigated by
studying the associated variability in large-scale atmospheric
circulation
over the Euro-Atlantic
sector. Seasonal expansion in the Azores high pressure system may play
an
important role in the
time-lagged relationships. The potential seasonal predictability of
summer
U.K. temperatures during
the period 1972-2001 is assessed by cross-validated hindcasts and usable
predictive skill is found.
However, the presence and cause of temporal instability in the
time-lagged
relationships over longer
periods of time requires further investigation.
--
regards,
david
(add 17 to waghorne to reply)
Sounds an interesting report. I've not read it but the following URL's
give
the snow info' for early 2003 which I was surprised to observe
Unfortunatly the relationship between snow cover and UK temperatures broke
down last year. There was very high snow cover during the winter, but a lot
of melting during the spring. The relationship depends on the persistence of
winter snow cover through to late spring/early summer, which failed last
year. However this correlation is strong enough over the last 30 years that
it is possible to predict summer temperatures with reasonable skill relative
to climatology.
Adam
|