date: Mon Dec 1 15:13:50 2008
from: Phil Jones
subject: RE: Fall of temperatures around 1945
to: "Ian Strangeways"
Ian,
The Earth's atmosphere system is chaotic. Volcanoes alter
circulation oscillations by cooling the surface and warming the stratosphere.
The Sun does similar things through variations in cloud around the world.
The Sun's output needn't change hardly at all.
The various oscillations are know to change and have done since they were
discovered. This could be internal dynamics of the climate system, but
it is also likely that the major forcing factors are involved as well.
If the Sun suddenly increased its output - say by 5%, we all
wouldn't get warmer. The atmospheric circulation patterns would change
to attempt to still move the heat from the equator to the poles. Most regions
would get warmer but some cooler.
Cheers
Phil
At 14:43 01/12/2008, you wrote:
Phil
Thanks, that all looks fine.
But just one surprising thing:-
You say the sun (and volcanoes) cause the changes (of the temperature
anomalies), possibly by affecting the oscillations. But I was under the
impression that the sun was supposed to have no influence whatsoever (in the
short term anyway). Now you are saying it is a major factor. In what way
does the sun act to cause the changes. It's not through its variations in
the solar constant because that is very stable. So how?
Hopefully this really is the last question
Ian
-----Original Message-----
From: Phil Jones [[1]mailto:p.jones@uea.ac.uk]
Sent: 01 December 2008 13:01
To: Ian Strangeways
Subject: RE: Fall of temperatures around 1945
Ian,
Answers interspersed
Cheers
Phil
At 12:00 01/12/2008, you wrote:
>Phil
>
>Thanks. I will include a note that SSTs for this period are being reviewed
>and describe the expected changes.
>
>I hope you don't mind one more set of questions (that will help to explain
>the temperature anomaly charts). I don't expect to have to bother you again
>after this.
>
>
>1. Were the changes of temperature before about 1940 due mostly to natural
>causes? You say in one of your notes on my chapter 9 that they might in
part
>be anthropogenic, and that I should not be categorical. I assume that the
>answer is 'we don't know for sure'
Yes, if anthropogenic explains much of the trend since the 1970s, then
it should also explain a small part of the changes before 1940.
>2. Were these natural causes mostly or entirely changes in the SOI, the PDO
>and the other oscillations?
No the natural factors are the Sun and volcanoes. How these
factors influence
the SOI, PDO and other oscillations is a factor also.
The SOI, PDO and others are natural modes of variability - that
the atmosphere likes.
Solar changes and volcanoes may push the atmosphere towards one of
these modes.
Anthropogenic forcing is likely to manifest itself as changes in
atmospheric modes.
>3 I assume that volcanoes affect just individual years (e.g. 1991).
Volcanoes probably affect the year after and the year after that.
So for Pinatubo,
you'd expect to see the effects in 1992 and 1993 (for a 1991 eruption).
>4. I assume that post 1975 some of the changes are still due to the SOI and
>PDO (especially in view of the big jumps in their indexes at that time).
Possibly, but blaming the changes on an Oscillation doesn't help
that much as we've
no idea why the oscillation change. See the earlier argument in Q2.
>4. Is proof of CO2 involvement post 1975 derived entirely from models or is
>there evidence in the actual instrumental data?
Mostly from models - a la Ch 9 of the IPCC Report.
>Ian
>
>
>-----Original Message-----
>From: Phil Jones [[2]mailto:p.jones@uea.ac.uk]
>Sent: 01 December 2008 09:49
>To: Ian Strangeways
>Subject: RE: Fall of temperatures around 1945
>
>
> Ian,
> I am only going on the ppt figure I sent you a week or more ago.
> I am awaiting the first draft of the SST adjustment paper (for the
>1940s/50s)
> but am not expecting this until the spring.
>
> Cheers
> Phil
>
>At 15:15 27/11/2008, you wrote:
> >Phil
> >
> >I hope you do not think I am trying to argue for cooling in the SH SST to
>be
> >difficult or confrontational. (See my last email).
> >
> >I am genuinely puzzled why the SH land air temperature fell after 1945 if
> >the SST did not also fall (after correction). If my logic is wrong please
> >say so. I am more than ready to be corrected.
> >
> >I am also aware that I am pestering you rather frequently at the moment.
> >
> >Ian
> >
> >-----Original Message-----
> >From: Phil Jones [[3]mailto:p.jones@uea.ac.uk]
> >Sent: 24 November 2008 16:51
> >To: Ian Strangeways
> >Subject: Re: Fall of temperatures around 1945
> >
> >
> > Ian,
> > The issue here is that in the SH, the SST dominates, so correcting
>this
> > will make the SH cooling less. I don't think the fall in SH SST is
real.
> > If the SH land shows a fall, you'd need to ensure this wasn't just a
> > response to La Nina events.
> >
> > Cheers
> > Phil
> >
> >
> >At 12:04 24/11/2008, you wrote:
> > >Phil
> > >
> > >I am ploughing through chapter 9 trying to get it right, accurate
> > >and fair. In rewriting the section about the land air temperature of
> > >the SH, I see that the temperature there fell quite quickly in the
> > >mid 1940s (and suddenly warmed in the late 1950s). We discussed this
> > >earlier and so I am reluctant to raise the matter again, but in an
> > >earlier email you said that the fall in SH SST in the mid 1940s was
> > >not real but due to the change from ERI to buckets after the war.
> > >Since the SH land air temperature fell in a similar way, might it
> > >not be that the fall in SST was also (at least in part) real?
> > >
> > >In the NH, the land air temperature did not fall at all around 1945
> > >and neither did the SST (much)
> > >
> > >Ian
> > >
> >
> >Prof. Phil Jones
> >Climatic Research Unit Telephone +44 (0) 1603 592090
> >School of Environmental Sciences Fax +44 (0) 1603 507784
> >University of East Anglia
> >Norwich Email p.jones@uea.ac.uk
> >NR4 7TJ
> >UK
>
>---------------------------------------------------------------------------
>-
>
>Prof. Phil Jones
>Climatic Research Unit Telephone +44 (0) 1603 592090
>School of Environmental Sciences Fax +44 (0) 1603 507784
>University of East Anglia
>Norwich Email p.jones@uea.ac.uk
>NR4 7TJ
>UK
>---------------------------------------------------------------------------
-
Prof. Phil Jones
Climatic Research Unit Telephone +44 (0) 1603 592090
School of Environmental Sciences Fax +44 (0) 1603 507784
University of East Anglia
Norwich Email p.jones@uea.ac.uk
NR4 7TJ
UK
----------------------------------------------------------------------------
Prof. Phil Jones
Climatic Research Unit Telephone +44 (0) 1603 592090
School of Environmental Sciences Fax +44 (0) 1603 507784
University of East Anglia
Norwich Email p.jones@uea.ac.uk
NR4 7TJ
UK
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