Is there a scientific consensus on global warming?

Science achieves a consensus when scientists stop arguing. When a question is first asked – like ‘what would happen if we put a load more CO2 in the atmosphere?’ – there may be many hypotheses about cause and effect. Over a period of time, each idea is tested and retested – the processes of the scientific method – because all scientists know that reputation and kudos go to those who find the right answer (and everyone else becomes an irrelevant footnote in the history of science). Nearly all hypotheses will fall by the wayside during this testing period, because only one is going to answer the question properly, without leaving all kinds of odd dangling bits that don’t quite add up. Bad theories are usually rather untidy. But the testing period must come to an end. So a consensus in science is different from a political one. Lead author John Cook created a short video abstract summarizing the study: Basic rebuttal written by GPWayne

Climate Science as Culture War The public debate around climate change is no longer about science—it’s about values, culture, and ideology. South Florida Earth First members protest outside the Platts Coal Properties and Investment Conference in West Palm Beach. (Photo by Bruce R. Bennett/Zum Press/Newscom) In May 2009, a development officer at the University of Michigan asked me to meet with a potential donor—a former football player and now successful businessman who had an interest in environmental issues and business, my interdisciplinary area of expertise. The meeting began at 7 a.m., and while I was still nursing my first cup of coffee, the potential donor began the conversation with “I think the scientific review process is corrupt.” As we debated each point, he turned his attack on me, asking why I hated capitalism and why I wanted to destroy the economy by teaching environmental issues in a business school. I turned to the development officer and asked, “What’s our agenda here this morning?” Scientific vs.

Keeping Climate Stories in Context Update: 3 p.m. ET | If the amount of personal email that hit my inbox last night or the comment thread on Spencer Michel’s blog post featuring Anthony Watts is any indication, many of you care in some way, shape, or form about the NewsHour’s coverage of climate. Let me try and clear a couple of things up regarding what was on-air, what was online, when and why. Spencer Michels, our reporter on the story, posted a blog post and lengthier interview to our Rundown blog Monday evening, a couple of hours before the broadcast segment was on-air or online. This was one element; it was not the entire piece. The entire segment first aired on the broadcast around 6:28 p.m. Spencer will have another blog post today offering the views of other scientists in the broadcast concerned about the threats of climate change. Last night’s broadcast piece was one segment, which you might want to look at in the context of several other segments we’ve been doing at the NewsHour on climate.

Climate Change Denial: Heads in the Sand - Haydn Washington Humans have always used denial. When we are afraid, guilty, confused, or when something interferes with our self-image, we tend to deny it. Yet denial is a delusion. When it impacts on the health of oneself, or society, or the world it becomes a pathology. Climate Change Denial explains the social science behind denial.

Just what is this Consensus anyway? We’ve used the term “consensus” here a bit recently (see our earlier post on the subject), without ever really defining what we mean by it. In normal practice, there is no great need to define it – no science depends on it. But it’s useful to record the core that most scientists agree on, for public presentation. The consensus that exists is that of the IPCC reports, in particular the working group I report (there are three WG’s. By “IPCC”, people tend to mean WG I). Fortunately that report is available online for all to read at The main points that most would agree on as “the consensus” are: The earth is getting warmer (0.6 +/- 0.2 oC in the past century; 0.1 0.17 oC/decade over the last 30 years (see update)) [ch 2] People are causing this [ch 12] (see update) If GHG emissions continue, the warming will continue and indeed accelerate [ch 9] (This will be a problem and we ought to do something about it)

Signals and noise. Mass-media coverage of climate change in the USA and the UK