date: Thu, 05 Mar 2009 23:22:56 +0000
from: Adrian Simmons <adrian.simmons@ecmwf.int>
subject: Re: Paper causing a stir
to: Phil Jones <p.jones@uea.ac.uk>

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Thanks, Phil.

 From just reading the abstract, I think I would have rejected it, as I 
would not trust the trends in the original NCEP reanalysis, which is 
from a production system which is a generation earlier than ERA-40 - and 
ERA-40 needs to be used with caution as one goes higher. The NCEP trends 
at the tropopause and in the lower stratosphere are certainly way off 
the mark.

I'm currently resisting the temptation to look at humidity trends in 
ERA-Interim above 850hPa. I think we have enough to present in our 
current paper, and I'd like to give priority to finishing writing it. I 
suspect as one gets to the middle and upper troposphere, the ERA 
humidities will shift as the satellite observing system changes, and as 
radiosonde instruments change. To date we've not implemented any bias 
correction/homogenisation of sonde humidities - for the future we hope 
that some proposed work by June Wang, Aiguo Dai and Leo Haimberger will 
get funding. June and Aiguo are visiting the Met Office this summer, and 
will be calling in at ECMWF.

All the best

Adrian


Phil Jones wrote:
> 
>>  Adrian et al,
>       The attached may be of interest - but it is just based on NCEP!
>  There are caveats, but they could have easily looked at ERA-40 or JARE-25.
>  Garth Paltridge is making waves on Climate Audit about this paper being
>  rejected by J. Climate.
> 
>  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 
> ----------------------------------------------------------------------------                                                                                 
> 

-- 
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Adrian Simmons
European Centre for Medium-Range Weather Forecasts
Shinfield Park, Reading, RG2 9AX, UK
Phone: +44 118 949 9700
Fax:   +44 118 986 9450
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