Climate change sceptics often cite the fact that predictions about global warming, droughts, increased hurricane activity and other harbingers of doom are based not on experimental science but merely on computer models. Indeed, the accuracy of predictions from these mere computer models has led to much intense debate and a lot of hot air.
A new study by meteorologists at the University of Utah, however, suggests that current climate models are quite accurate and could remain invaluable tools for those seeking to understand global warming trends and potentially help us in taking control of the climate in coming decades.
Thomas Reichler
In a paper entitled: How Well do Coupled Models Simulate Today’s Climate? published in April’s Bulletin of the American Meteorological Society, Thomas Reichler and Junsu Kim compared the output of climate models against observations of the present climate. They applied this simple-seeming method to about fifty different national and international climate models that have been developed over the past twenty years by researchers at major climate research centres in Australia, Canada, France, Korea, Russia, UK, and USA. Within their meta-analysis were predictions from the model used by the Intergovernmental Panel on Climate Change (IPCC) in its 2007 report.
Coupled models are becoming increasingly reliable tools for understanding climate and climate change, Reichler explains, and the best models are now capable of simulating present-day climate with accuracy approaching conventional atmospheric observations. He adds that, We can now place a much higher level of confidence in model-based projections of climate change than in the past.
The detailed study provides a renewed measure of trust in computational climate models and their predictions. Given the significance of climate change research in public policy, the team’s results can also provide a response to critics of climate change theories. Moreover, the University of Utah study points directly to the IPCC’s results and suggests that they reach an unprecedented level of realism.
Nevertheless, the researchers concede that although model-based projections of future climate are now considered to be more credible than ever before, there is still no way of knowing exactly how reliable are the projections such models make. There are simply too many variables involved in the future evolution of climate, feedback loops, changing oceanic acidity, desertification, volcanic activity, and efforts by humans to make amends for two centuries of pollution.
Further reading
Bulletin of the American Meteorological Society, 2008 (in press)
http://ams.allenpress.com/perlserv/?request=get-toc&issn=1520-0477
Thomas Reichler homepage
http://www.inscc.utah.edu/~reichler/
Intergovernmental Panel on Climate Change
http://www.ipcc.ch/
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