As a biologist, the fact that anthropogenic climate change is occurring has been explained to me throughout my education. We are interested in how crops might respond to global warming or what might happen to bees or coral reefs, not the basic question of whether or not it is happening at all. So that is why I was keen to attend John Cook’s talk at the Cabot Institute and learn a bit more about climate science and how it is perceived both within and outside the climate change science community
John Cook is the Climate Communication Fellow for the Global Change Institute at the University of Queensland, Australia. He runs the popular Skeptical Science blog, with the aim of explaining the scientific consensus on global warming. As he pointed out, his website has received a lot of criticism from people who do not agree that climate change is significantly driven by human effects.
The climate consensus
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| 97% of climate scientists agree that humans are responsible for climate change. Image credit: Skeptical Science |
Several studies, including John’s own (Cook et al., 2013), have shown that 97% of climate scientists agree that humans are significantly contributing to global warming. Doran and Zimmermann (2009) asked earth and climate scientists whether they thought that humans are significantly impacting global climate change and found that 97.4% agreed we are, while Anderegg and colleagues (2010) found that 97-98% of climate scientists agreed with the Intergovernmental Panel on Climate Change finding that anthropogenic greenhouse gases have been responsible for most of the Earth’s global warming.
Public perception of consensus
John described how the public does not seem to realise the extent of scientific agreement. When asked to estimate “how many climate experts agree that the global warming we are witnessing is a direct consequence of the burning of fossil fuels by humans”, the average response was 55%, a marked underestimate of the 97% consensus.
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| John is working to improve public understanding of the scientific consensus around global climate change. Image credit: Skeptical Science |
John showed a video from comedian John Oliver, who insisted that the only reason there was still an ongoing debate about climate change is because it is always portrayed with an “inherently misleading” 50:50 divide in representation. He goes on to hold a “mathematically fair” debate with three sceptics and 97 climate scientists, which ends with the immortal line, “I can’t hear you over the weight of scientific evidence”.
John Cook tried to bridge the consensus gap with a more balanced approach in his latest project, entitled “97 hours of consensus”. A total of 97 experts were asked to address the topic of humans causing global warming. Cabot’s own director, Professor Rich Pancost, was one of the scientists included.
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| Cabot Institute Director Professor Rich Pancost was a featured climate expert in the 97 Hours of Consensus project. Image credit: Skeptical Science |
John said that there is a lot of misinformation out there, causing confusion for the public who put their trust in scientific experts. He highlighted one particular website, the Global Warming Petition Project, which as of today [10 February 2014] had been signed by 31,487 American scientists urging their government to reject any limits on greenhouse gas emissions. As John pointed out, only 39 of these people are actually climatologists, therefore 99.9% of them are simply people with science degrees. As I mentioned earlier, I’m a biologist, but that doesn’t give me the expertise needed to decide whether anthropogenic climate change is occurring or what the causes are. I leave that to the experts. Instead, I focus my intellectual energy on ecosystems and how global warming (and other factors) will affect them.
Dr. Tamsin Edwards is a climate scientist who actively engages with people who differ in their opinions on what the science shows. In her blog, she states, “We can’t avoid scientific uncertainty, because we can’t perfectly measure or understand the universe. So we need to be very clear about what we know, what we don’t know, and the surprises we might face”. It can be tempting to avoid discussing difficult topics, but Tamsin inspires me (and hopefully her fellow climate scientists) to explain the science behind the conclusions and hopefully enable the public to make informed decisions too.
Do we need to close the consensus gap?
John said that he fears that if people don’t realise there is 97% scientific consensus about anthropogenic climate change, they won’t accept that it is happening and/or care enough to do anything about it. In the video abstract for his 2013 paper, John states that, “This misperception has real world consequences. When people correctly understand that the scientists agree, they are more likely to support policy that mitigates climate change”.
In the UK, several polls over the past five years have looked at what people consider the main cause of global climate change. Where two options (humans versus natural causes) were given, 43-71% of respondents chose humans as the main driver of global warming. These results were diluted when a third option (both human and natural causes) was given, however it is encouraging to note that only around 10-15% blamed natural processes alone.
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| Carbon Brief compared UK participants’ opinions on what causes climate change. Image credit: Carbon Brief |
The weekend following John’s talk was a perfect example of a possible change in public opinion of climate change globally. Hundreds of thousands of people marched in cities across the world in the People’s Climate March, including a couple thousand locally in Bristol. This was the largest climate march in history. The biggest turnout was in New York, where over 300,000 people called for action from the UN climate summit, which convened in the city on Tuesday 23 September 2014. UN Secretary General Ban Ki-moon marched with the crowd, an unusual move highlighting the importance of the event. He said, “Action on climate change is urgent. The more we delay, the more we will pay in lives and in money”.
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This blog is written by Sarah Jose, Cabot Institute, Biological Sciences, University of Bristol
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Sarah Jose
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