The Culture of Climate Change Science and Skepticism

While the IPCC’s consensus approach acknowledges uncertainties, defenders of the IPCC consensus have expended considerable efforts in the ‘boundary work’ of distinguishing those qualified to contribute to the climate change consensus from those who are not [4]. These efforts have characterized skeptics as small in number [13], extreme [50], and scientifically suspect [14]. These efforts create temptations to make illegitimate attacks on scientists whose views do not align with the co...

 Defining "Uncertainty"

‘Uncertainty’ is a complex and multifaceted property, sometimes originating in a lack of information, and at other times from quite fundamental disagreements about what is known or even knowable (Moss and Schneider, 2000). Furthermore, scientists often disagree about the best or most appropriate way to characterize these uncertainties: some can be quantified easily while others cannot. Moreover, appropriate characterization is dependent on the intended use of the information and the parti...

 The Problem with Occam's Razor

In climate forecasting, the situation is more equivocal: the theory about the greenhouse effect is strong, which supports more complicated models. However, temperature data is very noisy, which argues against them. Which consideration wins out? We can address this question empirically, by evaluating the success and failure of different predictive approaches in climate science. What matters most, as always, is how well the predictions do in the real world. I would urge caution against reducin...

 Conclusions of the IPCC

This IPCC finding makes several different assertions, each of which is worth considering in turn. First, it claims that atmospheric concentrations of greenhouse gases like CO2 are increasing, and as a result of human activity. This is a matter of simple observation. Many industrial processes, particularly the use of fossil fuels, produce CO2 as a by-product.18 Because CO2 remains in the atmosphere for a long time, its concentrations have been rising: from about 315 parts per million (ppm) wh...