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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.
"I suspect that the higher level of belief among ocean sciences and particularly geophysics represents second order belief (i.e. support for a perceived consensus) rather than personal research on AGW detection/attribution or a careful survey of the literature. How to square this with the oft reported 97% consensus? Well, ‘climate scientists’ in these surveys typically includes economists, ecologists etc., nearly all probably representing second order belief."
The survey Verheggen et al. (2014) found that scientists who work specifically on the physical science basis of climate change (known as WG1 for short), especially experts in attribution and aerosols, tend to believe humans are responsible for a greater proportion of the observed global warming than other scientists working in climate science who may, in some cases, have a "second-order belief" (see figure 2 in that study).
Overall, studies show 91% to 97% consensus among experienced climate scientists.
"the narrative of the 'spiral of death' for the sea ice has been broken ... It remains unclear as to what extent the decline in sea ice over the past decades is caused by natural variability versus greenhouse warming. Whether the increase in 2013 is a one year blip in a longer declining trend, or whether it portends a break in this trend remains to be seen."
"what the heck does the ‘climate change consensus’ even mean any more? The definition of climate change consensus is now so fuzzy that leading climate change skeptics are categorizing themselves within the 97%."
Here's what it means: the scientist self-ratings survey included in Cook et al. (2013) found a 96% consensus that humans are responsible for most of the current global warming, among papers that explicitly quantified whether or not humans were responsible. (This was not originally stated in the paper, but can be seen in the anonymized raw data of The Consensus Project.)
The contrarian Roy Spencer did claim to be part of the "97% consensus". The number 97% was produced with different criteria but The Consensus Project database shows that his claim is false. (Judith Curry herself did have two old papers among the 97%, but has published no papers stating whether or not humans cause most of the observed warming.)
"This is “hide the decline” stuff. Our data show the pause, just as the other sets of data do. Muller is hiding the decline"
Global warming apparently slowed down, but did not stop over reasonable averaging periods (more than 10 years). The slowdown is now over. The slowdown may have partly been an illusion produced by 1998 (an unusually hot year), plus a lack of arctic data (coverage bias) during a time when arctic regions were warming quickly. Instrumental bias may also be a factor. Ocean heat content continued rising during the slowdown.
"I just finished listening to Murry Salby’s podcast on Climate Change and Carbon. Wow. [...] If Salby’s analysis holds up, this could revolutionize AGW science."
"There is no question that the diagrams and accompanying text in the IPCC TAR, AR4 and WMO 1999 are misleading. I was misled. Upon considering the material presented in these reports, it did not occur to me that recent paleo data was not consistent with the historical record....It is obvious that there has been deletion of adverse data in figures shown IPCC AR3 and AR4, and the 1999 WMO document. Not only is this misleading, but it is dishonest"