The body of evidence for climate change is strong and convincing, and multiple lines of evidence show the changes are caused largely by human activities. The consensus among scientists about the reality of the phenomenon is also convincing.
But from the nature of public discussions on the subject today – at least in the US – that consensus might not be apparent. And somehow the discussion has become a “debate,” which is often divided down political party lines.
“We have to make it clear that the ice sheets are not Republicans or Democrats – they don’t have a political agenda as they disappear,” said Michael Mann, a physicist at Pennsylvania State University, who has been at the recent forefront of climate research. “Certain facts cannot be denied. We have to find a way to steer the conversation to a good faith debate about what we can do about the problem, not this bad faith debate about the reality of it.”
Mann spoke to over 600 writers and journalists on November 7, 2010 at the combined meetings of the National Association of Science Writers and the Council for the Advancement of Science Writing, held at Yale University this week.
Why has the public discourse become so polarizing and why is there a fair amount of legislators and the public who now think that climate change is an elaborate hoax?
Mann said there has been a large, well funded campaign to manufacture misinformation about climate change, similar to how tobacco companies muddied the waters in the 1960’s on how smoking causes lung cancer and emphysema. It’s no secret that many climate change deniers have ties to the fossil fuel industry.
Mann referred specifically to an infamous memo sent out by GOP political consultant Frank Luntz in 2002 to President George Bush, “which basically said that if the public comes to understand the reality of this problem they will demand policy action to deal with it,” Mann said, “and so you need to manufacture doubt and controversy and uncertainty and cultivate a set of scientists who can act for advocates essentially for fossil fuel industry. And that is what is happened.”
And the science became politicized. “If you can politicize something in today’s political environment,” Mann continued, “you can immediately get half the population on your side. Unfortunately the forces of anti-science — those who deny the science — have been very effective in politicizing the framing.”
But thousands of scientists from almost 200 countries around the world agreed on the most recent Intergovernmental Panel on Climate Change (IPCC) report which said most of the observed increases in global average temperatures is very likely due to the observed increase in anthropogenic greenhouse gas concentrations. Additionally, the US National Academy of Sciences, the National Academies of all the G-8 nations, the American Association for the Advancement of Science and several other scientific bodies have all issued equivalent statements of consensus of the reality of human-caused climate change.
“Certain facts cannot be denied because you don’t like the implications,” Mann said.
Mann is probably best known for known for his “hockey stick” reconstruction of past climate, (Nature, 1998) which shows the world is warmer now than it has been for at least 1000 years. The “hockey stick” has been attacked by climate change deniers, and while new research has better defined the data, it has not been disproven, nor is it the only line of evidence for global warming.
“The hockey stick is not ‘the’ pillar of evidence for the reality of climate change,” Mann said. “There are multiple pillars that include just the basic understanding of chemistry and physics. But it is one of the more visually compelling pieces of evidence for warming.”
Mann conceded that various other studies and reconstructions of past climate data don’t agree entirely and that there are uncertainties of how much warming will continue because the predictions are based on models, which attempt to predict the future.
“There are legitimate uncertainties, but unfortunately the public discourse is so far removed from where the scientific discourse and controversies actually are, “Mann said. “There is not an uncertainty of the reality of climate change, that sea levels are going to rise, that arctic sea ice will be gone in a few decades or a whole lot of other areas, but we do have an uncertainty in our ability to project regional climate change.”
Mann said scientists don’t completely understand the El Nino and La Nina affects, how cloud feedback will influence the warming and other modeling issues.
However, Mann said, the science has improved over the past few years, and still, there is enough evidence for not just a hockey stick, but an entire hockey league.
“Every reconstruction reveals that the warming is indeed anomalous in a very long term context. Global temperatures are running the highest they have ever run. The twelve month running averages are warmer than they have ever been in documented history. There is no cooling of the globe and no decline to hide,” Mann said referring to the “Climategate” emails that were stolen from East Anglia climate research center and leaked just a few weeks before the Copenhagen climate summit in late 2009.
“Hackers stole thousands of emails –private correspondences between scientists,” said Mann, “and their words were cherry picked, taken out of context and distorted to make it sound like scientists were engaged in some sort of hoax.”
‘Hide the decline’ actually meant the scientists were going to remove unreliable tree-ring data, not cover up any decline in temperatures.
Mann said the real crime was the illegal theft of private correspondence, in addition to the moral crime of intentionally distorting what scientists believe and think.
Mann took his audience to task by saying, “I’d like to say the mainstream media recognized the manufactured controversy for what is was, but they didn’t, entirely.” He also admitted that scientists have not done all they could in the past to make the science clear and their words convincing.
But looking at the current political climate, Mann asked for journalists’ help in the future.
“No doubt we are in for a period of months or even years where climate science is likely to be subject to the sort of politically motivated inquisition that we haven’t seen, frankly, since the 1950’s,” he said. “It is necessary and important for the scientific community to do the best it I can to defend itself from this oncoming attack, and frankly, we are entirely reliant on the willingness of the mainstream media to serve in its role as the critical and independent arbiter and not just report the two sides of the so-called debate, but to actually establish what is fact and what is fiction. The scientists will not be successful against the attack that is coming unless the media is serving its role.”
Mann ended his talk with a picture of his daughter enthralled by a polar bear at a zoo. “I don’t want to have to tell my daughter that polar bears became extinct because we failed to counter a well funded effort to distract the public,” he said.
Note: For any reader who thinks they need to leave a comment to debate the climate change science, before posting, please take a look at the following information:
RealClimate.org -- Mann and other climate scientists answer questions and discuss climate change data
NASA’s Global Climate Change Website. Lots of graphs, images and information.