date: Tue, 09 Mar 2004 15:21:43 +0000
from: Tim Osborn <t.osborn@uea.ac.uk>
subject: Fwd: Re: Anthropogenic forcing
to: Keith Briffa <k.briffa@uea.ac.uk>

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So that's what's so interesting!

Tim


>Date: Tue, 09 Mar 2004 15:04:17 +0000
>From: Simon Tett <simon.tett@metoffice.com>
>Subject: Re: Anthropogenic forcing
>To: Tim Osborn <t.osborn@uea.ac.uk>
>Reply-to: simon.tett@metoffice.com
>Organization: Met Office
>X-Accept-Language: en, en-us
>User-Agent: Mozilla/5.0 (Windows; U; WinNT4.0; en-US; rv:1.4) Gecko/20030624
>  Netscape/7.1 (ax)
>
>Hi Tim,
>         its the time development -- slow steady increase till 1970 or so 
> than massive and rapid increase beyond that.  Forcing is linear so adding 
> should be OK.
>
>Simon
>
>Tim Osborn wrote:
>
>>Simon - sorry, you'll need to illuminate me here, as I'm not quite sure 
>>what it shows / what is interesting!  Is it that the total anthropogenic 
>>forcing since 1750 is < 1 W/m^2, whereas IPCC give a best estimate 
>>somewhat higher than this (though with large aerosol-related uncertainty 
>>that means 1 W/m^2 is in the range of possibilities).
>>Also, is it valid to add/subtract forcings likes this (anthro minus 
>>natural) - are they really additive, or do they have an interaction term?
>>Tim
>>
>>At 10:58 09/03/2004, Simon Tett wrote:
>>
>>>Dear all,
>>>         I thought you might like to see this. Attached is total 
>>> global-mean anthropogenic adjusted forcing  compates from ALL - 
>>> Natural. I think it shows something quite interesting....
>>>
>>>Simon
>>>--
>>>Dr Simon Tett  Managing Scientist, Data development and applications.
>>>Met Office       Hadley Centre (Reading Unit)
>>>Meteorology Building,  University of Reading Reading RG6 6BB
>>>Tel: +44 (0)118 378 5614  Fax +44 (0)118 378 5615
>>>Mobile: +44-(0)77 538 80696
>>>I work from home about 2 days/week. Tel: +44 (0)20 8874 2751
>>>E-mail: simon.tett@metoffice.com   http://www.metoffice.com
>>>
>>Dr Timothy J Osborn
>>Climatic Research Unit
>>School of Environmental Sciences, University of East Anglia
>>Norwich  NR4 7TJ, UK
>>e-mail:   t.osborn@uea.ac.uk
>>phone:    +44 1603 592089
>>fax:      +44 1603 507784
>>web:      http://www.cru.uea.ac.uk/~timo/
>>sunclock: http://www.cru.uea.ac.uk/~timo/sunclock.htm
>
>--
>Dr Simon Tett  Managing Scientist, Data development and applications.
>Met Office       Hadley Centre (Reading Unit)
>Meteorology Building,  University of Reading Reading RG6 6BB
>Tel: +44 (0)118 378 5614  Fax +44 (0)118 378 5615
>Mobile: +44-(0)77 538 80696
>I work from home about 2 days/week. Tel: +44 (0)20 8874 2751
>E-mail: simon.tett@metoffice.com   http://www.metoffice.com

Dr Timothy J Osborn
Climatic Research Unit
School of Environmental Sciences, University of East Anglia
Norwich  NR4 7TJ, UK

e-mail:   t.osborn@uea.ac.uk
phone:    +44 1603 592089
fax:      +44 1603 507784
web:      http://www.cru.uea.ac.uk/~timo/
sunclock: http://www.cru.uea.ac.uk/~timo/sunclock.htm

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