Archive for the ‘refuting the skeptics’ Category

Solar output increases account for part of (not all) the observed climate warming

Wednesday, April 1st, 2009

If the skeptics read the scientific literature, they would know that climate scientists do not ignore solar output changes in attributing past, present, and future climate forcing agents. I was shocked when The Other Paper published part of Jym Ganal’s rant that solar output changes were solely responsible for the observed climate warming; an embarrasingly (for him) simplistic claim that ignores the reality that solar output changes are one of a long list of forcing factors included in climate simulations, the latter aimed at partitioning the relative importance of various climate forcings.

As put forth in the The Intergovernmental Panel on Climate Change (IPCC) 2007 Fourth Assessment Report, that “Changes in the atmospheric abundance of greenhouse gases and aerosols, in solar radiation and in land surface properties alter the energy balance of the climate system.”. There is no silver bullet, as Ganahl simplistically suggests. According to a growing body of science summarized by the IPCC each 5 or so years since 1991, science’s best estimate for the role of changing solar output in climate change is that increasing solar output accounts for between 3% and 19% of the observed change in the energy balance of the climate system. Average temperature at the surface reflects the changing heat energy contained in the climate system. If Ganahl were a scientist worth his 40-year-old “Seal of Approval”, he would review all relevant and credible sources of information instead of putting forth only one of a myriad of factors that influence climate as a sole cause of warming. Yes, temperatures on Mars have increased because of increasing solar output. Again, that share on earth accounts for less than one fifth of the observed warming.

It’s unfortunate, but, the reality is that unless civilization stabilizes its non-sustainable impact on the Earth’s atmosphere, ecosystems, and resource bases, we collectively will face economic and environmental disruptions that will make us look back on the recent market meltdown as not nearly so bad.

Do your homework Ganahl. All, please see: the IPCC summary for policy makers figure SPM.2
Yours Realistically,

Jason E. Box, contributing author to The 2007 Intergovernmental Panel on Climate Change Fourth Assessment Report