date: Tue, 17 Jul 2007 15:26:15 +0100 from: Tim Osborn subject: Re: carbon emissions to: paul41@webone.com.au Dear Paul, there is no absolute "proof" in science, but rather observations together with explanations for those observations that are called hypotheses, theories or laws (depending on the degree to which the explanation has been tested, how well it has passed those tests, and the degree to which it is generally accepted). The greenhouse effect provides the link between extra carbon emissions and global warming, and is often described as a theory, given that it has been relatively well tested and as a result is generally accepted. The greenhouse effect theory is complex, in that it depends upon many different processes each behaving according to various laws, e.g. the size of the increase in atmospheric CO2 concentration following extra carbon emissions is determined by various chemical and biological processes that remove some of the extra CO2, e.g. the effect of the remaining extra CO2 on the heat balance of the Earth is determined by various physical laws that quantify the emission and absorption of radiation by different gas molecules and that determine the flow of the atmosphere etc. As a result, it is difficult to point you towards a single piece of research that is, on its own, able to demonstrate testing of the greenhouse effect theory, because acceptance is based on a huge number of studies that have tested individual processes or components within this complex theory, and even those studies that have attempted to test the overall sequence of events from carbon emissions through to global warming/climate change could not be relied upon individually -- rather it is the combined message from multiple studies that has led to widespread acceptance of the greenhouse effect theory. The Intergovernmental Panel on Climate Change (IPCC) has reviewed and summarised many of these strands of evidence, so I would suggest that you read their recently-published summary for policymakers available here: http://ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Pub_SPM-v2.pdf especially, for example, the diagram on page 11. This summary is based on a full report, the chapters of which are available here: http://ipcc-wg1.ucar.edu/wg1/wg1-report.html Chapters 1 and 9, together with the studies that they refer to, might be of most interest in terms of the development and subsequent testing of the greenhouse effect theory. I hope you find this reply useful. Best regards Tim >-----Original Message----- >From: Margaret and Paul [mailto:paul41@webone.com.au] >Sent: Monday, July 16, 2007 10:49 AM >To: cru@uea.ac.uk >Subject: carbon emissions > >Hi, > >I am an ordinary person, trying to fathom the whole global warming >issue. > >I am trying to establish the proof that carbon emissions are causing >global warming. > >Can you direct me to any research that proves this point. > >I am looking for proof, rather than an association. > >Many thanks, > >Paul Wright 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