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Anthropogenic Global Warming

The whole subject of anthropogenic global warming (AGW) has become very polarized, mainly because it has been removed from the realm of scientific research and co-opted by politicians and environmental ideologues.  Political and ideological opinions range from the "true believers," who fervently and sincerely think AGW is a scourge that will have catastrophic consequences if we do not act swiftly to radically alter our industrial society and general lifestyle, to the "deniers," who are equally convinced and just as sincere in thinking that it is all just a gigantic hoax being perpetrated to advance a political ideology and a radical environmentalist agenda.  The scientific evidence actually suggests that the truth lies somewhere in between those two extremes, although precisely where between them remains unclear and will likely stay that way for years if not decades.

The Intergovernmental Panel on Climate Change (IPCC) has released four assessment reports, the most recent in 2007.  Because of their prominence, these reports have come to form the basis of most if not all discussions regarding global warming, greenhouse gases, and the changes in climate due to even higher temperatures that are predicted by computer models.  The Summary for Policy Makers (SPM) that is released as part of each assessment report expresses increasing confidence that the planet is warmer than anytime in at least the last 1000 years, that the warming happened faster than in the past when it was due to natural variations, that more warming will occur, that human carbon dioxide (CO₂) emissions are mainly responsible, that CO₂ levels are higher than in the last 650,000 years, and that significant changes in climate, rainfall, drought, snow, ice, severe storm frequency and intensity, rate of sea level rise, species extinctions, and numerous other maladies have already been detected or can be expected in the future.

Due to the IPCC reports, some politicians have taken it upon themselves to declare that the debate is over, the science is settled, and there is a consensus among scientists.  However, that is simply not true.  While it may be true that the number of scientists who are proponents of the conclusions of the IPCC reports outnumber the skeptics willing to publicly disagree, many scientists are still very much divided on some tenets of AGW theory and do not accept all of the IPCC conclusions.  The skeptical scientists have expressed doubts about temperatures being higher or rising faster than in the past, how much warming has occurred, if the warming trend is still continuing, how much more warming may occur, if warming has been or will be harmful, how much warming is actually attributable to human contributions to CO₂ levels, whether CO₂ levels were higher in the past, if even higher CO₂ levels are dangerous or could have some benefits, if the computer models accurately account for all climate variables, and if the solutions that are being proposed are rational, reasonable, or will even have any effect.

So, what really is the truth about AGW and its probable consequences?  We do not claim to have the answer, nor do we believe it is our mission to attempt to sway you one way or the other.  Besides, if you have already made up your mind, we probably couldn't convince you to change it even if we wanted to.  Our goal is solely to provide you with access to observational data, facts, scientific research, information, news, and opinion from both sides of the debate.  After reviewing that information you will have a clear understanding of the issues involved, the uncertainties remaining, and be able to make your own determination about how much of a threat AGW poses and what should be done about it.  If you still have an open mind, you will find the information necessary to make an informed decision.  If you already know where you stand, you will find material to support your opinion, no matter which side you are on, since some of the research, observations, and model predictions are in conflict or they be used to support more than one hypothesis.