How do meteorologists fit into the 97% global warming consensus?

Several surveys have found relatively low acceptance of human-caused global warming amongst meteorologists. For example, a 2009 survey found that among Earth scientists, only economic geologists (47 percent) had lower acceptance of human-caused global warming than meteorologists (64 percent). A new paper by social scientists from George Mason University, the American Meteorological Society (AMS), and Yale University reports results from a survey of members of the AMS to determine the factors associated with their views on climate change.

Climate Scientists and Meteorologists, Apples and Oranges

Predictably, many climate contrarians have already misrepresented this paper. In fact, the Heartland Institute (of Unabomber billboard infamy) misrepresented the study so badly (and arguably impersonated the AMS in a mass emailing), the AMS executive director (who is a co-author of the paper) took the unusual step of issuing a public reprimand against their behavior.

The misrepresentations of the study have claimed that it contradicts the 97 percent expert consensus on human-caused global warming. The prior studies that have found this high level of consensus were based specifically on climate experts – namely asking what those who do climate science research think, or what their peer-reviewed papers say about the causes of global warming.

The AMS on the other hand is not comprised primarily of climate experts. Some of its members do climate research, but only 13 percent of survey participants described climate as their field of expertise. Among those respondents with climate expertise who have published their climate research, this survey found that 93 percent agreed that humans have contributed significantly to global warming over the past 150 years (78 percent said it's mostly human-caused, 10 percent said it's equally caused by humans and natural processes, and 5 percent said the precise degree of human causation is unclear, but that humans have contributed). Just 2 percent of AMS climate experts said global warming is mostly natural, 1 percent said global warming isn't happening, and the remaining 4 percent were unsure about global warming or human causation.

The authors also note that they asked about contributions to global warming over the past 150 years, whereas climate scientists are most confident that humans are the dominant cause of global warming over the past 50 years. Some survey participants sent emails implying that if the question had more narrowly focused on the past 50 years, even more respondents might have said that global warming is mostly human-caused.

Importantly, most AMS members are not climate researchers, nor is scientific research of any kind their primary occupation (for example, weather forecasters). Among those AMS members who haven't recently published in the peer-reviewed literature, just 62 percent agreed that humans are causing global warming, with 37 percent saying humans are the main cause over the past 150 years.

The bottom line is that the previous studies finding 97 percent expert consensus on human-caused global warming are not directly comparable to this new study, which surveyed all AMS members, most of whom are not climate experts. The study's lead author, Neil Stenhouse, agrees that the Heartland Institute's James Taylor has misrepresented their study.

"Mr. Taylor's claims are highly misleading, but we expect that from someone with a long history of distorting the truth about global warming. We found high levels of consensus on global warming among the climate experts in our sample. You only see low levels of consensus in the sample if you also look at the views of people who are not climate experts."

What's Causing Meteorologist Skepticism?

When we actually examine the questions the study does investigate, as opposed to the contrarian approach of twisting the results to try and make them fit preconceived notions, it contains a lot of interesting information. The authors proposed four hypotheses to explain the variation in AMS members' views on global warming. They found evidence supporting each of the four hypotheses. In terms of predicting meteorologists' positions on human-caused global warming, listed in order from strongest to weakest, these were:

1) Perceived scientific consensus on global warming
2) Political ideology
3) Climate expertise
4) Perceived conflict among AMS members on global warming

Interestingly, the strongest single factor in predicting meteorologists' acceptance of human-caused global warming was their perception of the level of expert consensus on the subject. This result is consistent with previous research finding that people are more likely to accept this reality and support taking climate action if they're aware of the expert climate consensus. Like most people who are not expert in a particular field, most meteorologists also defer to the expert consensus...when they're aware that expert consensus exists. This is precisely why climate contrarians work so hard to deny that the climate consensus is real. The authors suggest tackling this misconception head-on.

"First, the strong relationship between perceived scientific consensus and other views on climate change suggests that communication centered on the high level of scientific consensus may be effective in encouraging engagement by scientific professionals."

Political ideology was the second strongest predictor of meteorologists' positions on global warming. Conservative AMS members were significantly more likely to doubt the reality of human-caused climate change. This tells us that the relatively high rate of rejections of the climate consensus isn't based on science, because the scientific evidence has nothing to do with politics.

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Posted by dana1981 on Monday, 2 December, 2013

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