cc: Phil Jones
,Mike Salmon , Keith Briffa ,Clare Goodess , "Aurelie Persechino" ,
date: Thu, 13 Jul 2006 12:36:23 +0100
from: Tim Osborn
subject: Re: BA festival - Global Warming
to: "Laura Middleton"
Dear Laura,
here is the next graph for the BA exhibit.
This one is from the IPCC TAR 2001 summary for policymakers (fig
SPM-2) if you want to read the detailed caption.
This is the "attribution modelling plot" listed under the
"Instrumental climate record" part of the CRU outline. Some
explanation of this graph:
-----------------------
The purpose is to see if we can understand the causes of past
temperature changes (the measured/observed changes are shown in red
in all cases).
The grey band in each panel are the range of temperatures simulated
by a climate model.
In the top left, the climate model is responding only to natural
changes in the sun's output and volcanic "dust". It is clear that
the observed warming cannot be explained by these natural changes.
In the top right, the climate model is responding only to
human-related changes ("anthropogenic"), principally increasing
greenhouse gas concentrations. The overall amount of observed
warming appears to be explained by these human-related effects, but
the timing of when the warming took place is not explained by these
human-related effects alone.
In the bottom panel, the climate model is responding to both natural
and human-related changes. It provides an excellent explanation of
the observed changes in temperature.
-----------------------
Cheers
Tim
Attachment Converted: "c:\eudora\attach\understandingpastwarming.png"
Dr Timothy J Osborn, Academic Fellow
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
**Norwich -- City for Science:
**Hosting the BA Festival 2-9 September 2006