To be honest, I'm often puzzled by perceptions that scientists are quite so divided on the subject. The following is not an attack on anyone here, I assure you, it's only that this subject sometimes surprises me and I wonder about the origins.
True, there are and always will be disagreements regarding scientific theories and that is a good thing. We always need debate to constantly challenge our understanding, as this ensures that theories can develop further and stand up to scrutiny.
In my experience, however, this great split in the scientific community about climate change just does not seem to exist. I've actually never met a scientist who disagreed with anthropogenic (i.e. human caused) climate change, although I know some will be out there.
That is anecdotal evidence, however, so let's see what the data out there actually says. A
recent article in Proceedings of the National Academy of Sciences of the United States of America (a prestigious journal) states:
Here, we uanthropogenic climate changese an extensive dataset of 1,372 climate researchers and their publication and citation data to show that (i) 97–98% of the climate researchers most actively publishing in the field surveyed here support the tenets of ACC outlined by the Intergovernmental Panel on Climate Change, and (ii) the relative climate expertise and scientific prominence of the researchers unconvinced of ACC are substantially below that of the convinced researchers."
(where "ACC" is "anthropogenic climate change")
In
a study from a few years earlier, in Eos Transactions of the American Geophysical Union, (
alternative link for those who don't have direct access) around 90% of scientists surveyed felt global temperatures had risen (question 1), compared to pre-1800 levels, and 82% felt that "human activity is a significant contributing factor in changing mean global temperatures" (question 2). Note that this was for a broad range of scientists, and that the "yes" vote for question 2 rose to 97.4% when only considering the replies of specialists in the field. One of the things I found most interesting, however, was Figure 1. This showed the answers to question 2 from members of the public and of scientific contributors in different categories. The percentage of members of the public who believed that human activity was
not significantly to blame was about five times higher than amongst scientists. It is worth asking why this is.
Alternatively, one could have a look
at a graph on Wikipedia that has compiled the results of different surveys of scientists. The percentage of scientists feeling that climate change is largely anthropogenic ranges between 82% - 98%. Further statements from organizations can be found
on NASA's web pages. So the surveys mentioned so far would appear to support my feeling that the public perceives a great scientific divide on climate change which scientists themselves do not perceive.
So where is the controversy coming from? Well, it is worth having a look at who is advocating climate change denial and who funds it.
An article in Scientific American describes the search to identify these sources:
In the end, Brulle concluded public records identify only a fraction of the hundreds of millions of dollars supporting climate denial efforts. Some 75 percent of the income of those organizations, he said, comes via unidentifiable sources.
And for Brulle, that's a matter of democracy. "Without a free flow of accurate information, democratic politics and government accountability become impossible," he said. "Money amplifies certain voices above others and, in effect, gives them a megaphone in the public square."
Powerful funders, he added, are supporting the campaign to deny scientific findings about global warming and raise doubts about the "roots and remedies" of a threat on which the science is clear.
There was also an interesting article in
The Guardian (if not using only US sources
), where it stated:
Conservative billionaires used a secretive funding route to channel nearly $120m (£77m) to more than 100 groups casting doubt about the science behind climate change...
Again, this is absolutely not an attack on anyone here, I've just been perplexed by the controversy I've often seen in the US media and so thought I'd chime in!