cc: "Allan, Rob" <rob.allan@metoffice.gov.uk>
date: Wed, 28 Mar 2007 13:13:33 +0100
from: philip.brohan@metoffice.gov.uk
subject: Re: WW2 marine data
to: Phil Jones <p.jones@uea.ac.uk>

Phil

 We've got quite a lot of evidence we need to look again at bias
adjustments for the mid-20th century: I've been doing some systematic
model-obs comparisons, and  John Kennedy has been looking at the
differences between SSTs from ships from different countries. What we
haven't yet done is sat down and derived some new adjustments and
uncertainties.

I've put a preliminary look at the new obs from the WW2 logs on the web
(http://brohan.org/hadobs/digitised_obs/docs/) there are some
interesting indications of biases in SST and night air temperature.
We're still short of obs for the Pacific though.

Clive's done some good work in the archives, and I'm hoping that
collaborating with him and the historians from Exeter we can have a
serious crack at making instrumental temperature series back past 1800.
I'm still keen on a 'climate of the 19th century' project - as well as
digitising more observations, we could use GCM runs and proxies to help
bias adjust the early instrumental observations, and make a credible
time-series back through the Tambora period - that would give us a wider
range in instrumental temperatures, and so help to calibrate longer
proxy reconstructions. But so far this is just an idea.

Cheers,

 Philip

On Wed, 2007-03-28 at 11:48 +0100, Phil Jones wrote:
> >  Philip,
>          Just had a coffee with Clive Wilkinson. He was telling me
>   of the progress with the WW2 logs and his finds for WW1 as
>   well.   I suggested he also look into log books during the
>   late 1870s as the RN were then doing SST and we then had
>   a Valpariso Fleet.
>        On the WW2 logs, hopefully these may resolve the
>   issue Daithi Stone talked to me about regarding the D&A
>   figure from WG1 SPM (the one with the continents and the
>   world oceans on). He was a little concerned about the obs
>   for the global oceans popping out of the model swathe around
>   1940, as it doesn't do this for the continents.
>      I guess if there are significant more obs in the E Eq Pacific
>   this issue could be nailed down. May relate to whether the
>   obs are bucket/intake and need adjustment or not.
> 
>      I told Clive, I'd be happy to be involved in Exeter Uni.
>   initiatives re their Inst for Maritime History.
> 
>   Cheers
>   Phil
> 
> 
> 
> 
> 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 
> ----------------------------------------------------------------------------                                                                                 
-- 
Philip Brohan,  Palaeoclimate Scientist
Met Office Hadley Centre for Climate Prediction and Research      
Tel: +44 (0)1392 884574    Fax: +44 (0)1392 885681


