"Dave C" wrote in message
...
Philip, out of interest if the most anomalous CET (1 year) was taken out
of
each decade and the mean recalculated would it have made much difference?
For example missing out 1963 in that decade.

A good point ... a 10 year period is just a useful and simple way of playing
with the statistics, but it is short enough for individual months to have a
significant influence of the final figures. However, I don't think excluding
single months would change the pattern that we have observed using the
decadal means. Taking out November 1963 would make the 60s colder,
drier and sunnier, but it would also change the circulation indices:

Period 1961-70 without'63
CET 6.2ºC 6.0
RR(E&W) 105mm 98
SSS(E&W) 57hr 56
Icelandic Low1004mb 1004
Azores High 1020 1021
55N05Wppp 1009 1011
UK Flow dirn 260º 280
UK pr gradient 5.2mb 4.6
Westerliness I 5.2mb 5.4
Southerliness I 0.1mb -0.2

So the decade (or perhaps that should be 'nonade') is colder, but it
has a negative southerliness index; it is also drier but the mean pressure
at 55N 05W is higher, etc etc.

Philip Eden

I would hate to think what February would show! I don't think December would
be too horrific.
November and February are no longer Winter months, at least in the South.

Here is the same exercise for December ... a month which
has not exhibited a gradual warming trend over the last
four decades. It is one of the very few months of the year
when the 90s were cooler than the 80s and 70s:

Period 1961-70 1971-80 1981-90 1991-2000
CET 3.5ºC 5.4 5.0 4.7
RR(E&W) 88mm 96 101 106
SSS(E&W) 48hr 42 43 45
Icelandic Low1003mb 999 996 996
Azores High 1021 1022 1022 1022
55N05Wppp 1010.7 1010.2 1010.6 1009.6
UK Flow dirn 260º 250 240 230
UK pr gradient 7.0mb 11.2 10.2 9.9
Westerliness I 7.3mb 11.2 9.8 9.6
Southerliness I 0.5mb 2.5 2.6 3.0

So the pressure gradient and the westerliness index
(not really independent, of course) seem to correlate
with the mean temperature, while the southerliness
index seems to be less important than it was in
November. It is probably significant that winter
southerlies can range from very mild to very cold
whereas November southerlies are more often very
mild than they are very cold. The pressure at
55N 05W seems only loosely linked to mean rainfall ...
the gradually backing of the flow (southwesterlies are
probably wetter than westerlies ...?) may also be
important.

Philip Eden

"danny" wrote in message
...
I would hate to think what February would show! I don't think December
would
be too horrific.
November and February are no longer Winter months, at least in the South.

Here in the North West of England I would suggest that November is rarely
cold and wintery. Just from memory we rarely have much severe frost before
Christmas

Admittedly here we are very coastal but I can only remember one occassion
where we had snow at sea level on Christmas day

Snowy weather tends to be January/February

Jim Webster

In article ,
danny writes:
I would hate to think what February would show! I don't think December would
be too horrific.
November and February are no longer Winter months, at least in the South.


Fair comment about February, but I don't think that November has ever
really been a winter month in the south (apart perhaps from a small
handful of very exceptional years, of which 1952 may be the most recent,
though you could also make a case for 1962). When I live, on low ground
in Surrey, in the last 40 years or so I can only remember one November
day that could be described as a day of "snow lying", and that was on
30th November in - I think - 1969.
--
John Hall

You can divide people into two categories:
those who divide people into two categories and those who don't

Thanks Philip. I actually meant taking out a whole year stats. This might
then show that there wasn't a "trend" but a particular period that hadn't
had a prolonged extreme event. i.e. 1963 for temp, 2003 or 1976 for
rainfall. Without being a statistical bore did you do a confidence limit or
significance test on the data sets? (sorry?!).
Dave
"Philip Eden" philipATweatherHYPHENukDOTcom wrote in message
.. .

"Dave C" wrote in message
...
Philip, out of interest if the most anomalous CET (1 year) was taken out
of
each decade and the mean recalculated would it have made much
difference?
For example missing out 1963 in that decade.

A good point ... a 10 year period is just a useful and simple way of
playing
with the statistics, but it is short enough for individual months to have
a
significant influence of the final figures. However, I don't think
excluding
single months would change the pattern that we have observed using the
decadal means. Taking out November 1963 would make the 60s colder,
drier and sunnier, but it would also change the circulation indices:

Period 1961-70 without'63
CET 6.2ºC 6.0
RR(E&W) 105mm 98
SSS(E&W) 57hr 56
Icelandic Low1004mb 1004
Azores High 1020 1021
55N05Wppp 1009 1011
UK Flow dirn 260º 280
UK pr gradient 5.2mb 4.6
Westerliness I 5.2mb 5.4
Southerliness I 0.1mb -0.2

So the decade (or perhaps that should be 'nonade') is colder, but it
has a negative southerliness index; it is also drier but the mean pressure
at 55N 05W is higher, etc etc.

Philip Eden

Fair point.
It is definately a less cold month here, seeming to be more an extension of
Autumn than the herald of winter. I guess the figures Phillip produced do
show the warming trends of this month, and proof Winter in England and Wales
starts in December.


Fair comment about February, but I don't think that November has ever
really been a winter month in the south

"Dave C" wrote in message
...
Thanks Philip. I actually meant taking out a whole year stats. This might
then show that there wasn't a "trend" but a particular period that hadn't
had a prolonged extreme event. i.e. 1963 for temp, 2003 or 1976 for
rainfall. Without being a statistical bore did you do a confidence limit
or
significance test on the data sets? (sorry?!).
Dave

Oh, heck, not for here! I was just presenting the information (plus a
few idle thoughts of my own) to provide some discussion material.

Philip Eden

Oh, heck, not for here! I was just presenting the information (plus a
few idle thoughts of my own) to provide some discussion material.

Philip Eden

...... fair enough! Just thought I'd been getting a bit trivial lately!

Cheers,
Dave

What caught my eye about the November figures was that although the
temperature record rose steadily the rainfall was more erratic. If the cause
was the dreaded global warming then one might expect both figures to climb
slowly.

Period 1961-70 1971-80 1981-90 1991-2000
CET 6.2ºC 6.6 6.8 7.2
RR(E&W) 105mm 87 85 128

In December the opposite is true. The temperature record is erratic and the
rainfall record climbs slowly.

Period 1961-70 1971-80 1981-90 1991-2000
CET 3.5ºC 5.4 5.0 4.7
RR(E&W) 88mm 96 101 106

Averaging the two sets of figures we get for Nov and Dec;
Period 1961-70 1971-80 1981-90 1991-2000
CET 4.9ºC 6.0 5.9 7.0
RR(E&W) 97mm 92 93 117

This seems to me to provide no clearer a message than the two months seen
separately. What I think it proves is that the climate is chaotic, and it may
be very difficult to tell whether we have upset the climate severely before it
is too late to act and prevent a disaster.

Cheers, Alastair.