I often read that 97% of climate scientists agree with “the consensus” on anthropogenic global warming (AGW), so I decided to finally buckle down and read the article that has given the latest currency to this claim. You can read it too, right here. The heart of it is contained in Table No.3:
You can see the 97.1% figure there, right in the first row. Done deal! But what does this really mean? Read for yourself, but here’s a summary:
- About 12,000 abstracts of papers on “climate” were culled from the Web, and distributed without names to twelve “citizen-science” researchers for rating.
- About 9,000 expressed no position on AGW.
- Of those that expressed a position, 97% “endorsed” the “consensus” view. What does that mean? Actually, the “endorsed” label was applied to any of three expressed positions to make the analysis simpler. To receive that rating, the abstract had to take one of the following positions:
- Explicitly state that humans are the primary cause of recent global warming
- Explicitly state humans are causing global warming, or refer to anthropogenic global warming/climate change as a known fact
- Imply humans are causing global warming. e.g., the research assumes greenhouse gas emissions cause warming without explicitly stating humans are the cause
Pretty broad array of opinion there all rolled up into that 97%, which is actually only 97% of the 1/3 that expressed a position. Could it be that those that did not express a position, 63%, just think it’s a trivial affair, not worth discussing? And of those that did express “affirmation,” it seems that just mentioning that CO2 does cause the earth to warm – no mention of how much, or over what period, or whether or not it is worrisome – puts you down with the “consensus” position.
So, we can state pretty definitively that those writers of published scientific papers who chose to express a view of AGW, do overwhelmingly agree that CO2 is a greenhouse gas and that human activity – not just burning fossil fuels – is contributing to changes in the climate. That’s a pretty safe set of propositions, but then, it is the nature of consensus to state the non-controversial.
NB: There is absolutely no mention of the real crux of the controversy, i.e., what to make of the projections for the next fifty and one hundred years that are contained in the IPCC Assessment Reports and other publications.