Last week I returned from an amazing Skeptic Society cruise along Alaska’s Inside Passage. During the cruise, we held a conference with 200 other Skeptics on “Glaciers and the Science of Climate Change,” with presentations by scientific experts on glaciers and climate. On day 3, we witnessed the glaciers melting away before our very eyes. At Glacier Bay National Park, we saw tons of ice calving away from Margerie and Johns Hopkins glaciers, causing huge booms to echo across the fjord. As our resident expert Dr. Bruce Molnia of the USGS pointed out during his presentation, over 95% of the glaciers of Alaska are stagnant or shrinking, and we saw several examples of these. Molnia has been studying Alaska’s glaciers for decades, and he showed stunning images of how much they have retreated in just the past century (such as the images of the retreat of Muir Glacier below, shot in 1941 and in 2004). If you recall the images of the vanished glacier’s in An Inconvenient Truth, some of those were from Molnia’s research. We billed the trip as “See ‘em before they vanish” but in the case of most of the glaciers, it’s already too late. If my 6- and 8-year-old sons repeat this trip decades later as grown men, there will be almost no glaciers to see at all.
Naturally, the conference focused on the scientific evidence about glacier retreat and global climate change. Our moderator Michael Shermer challenged us to show us the evidence that climate change is real and anthropogenic, and our speakers did so in spades. Much of this evidence was outlined in Chapter 10 of my new book Catatastrophes!, so I will not repeat all of it here. But some of the key points that came up again and again in the conference were:
1. The community of scientists who actually do climate research has long ago reached a consensus that anthropogenic global warming is real, and their consensus is about 95–99% depending upon the study (Oreskes, 2004; Doran and Kendall Zimmerman, 2009; Anderegg, 2010). This is as much agreement as you’ll see in science, comparable to scientific consensus about evolution or quantum physics or relativity. As I pointed out in previous posts, there are cranks who challenge the ideas of relativity or quantum physics, or creationists who deny evolution, but they do not represent the overwhelming scientific consensus.
2. The planet’s climate is clearly changing in a way that cannot be explained by simple climate cycles or warming since the Little Ice Age or any other cause. One only need look at the unprecedented disappearance of the world’s glaciers, ice caps, and permafrost, the temperature records from multiple sources all over the world, and many other lines of evidence to show that the planet is warming faster with higher levels of carbon dioxide than any time in the past 650,000 years at minimum (based on the EPICA ice core from Antarctica), and probably since the Ice Ages began over 2.5 million years ago. The fact that the North Pole is now ice-free open water in summer for the first time in 2 million years is shocking in and of itself. Where will Santa go?
3. Many people agree that climate is changing, but are not sure that humans are to blame. If they want proof, they can examine the huge array of data directly point to humans causing global warming. We can directly measure the amount of carbon dioxide humans are producing, and it tracks exactly with the amount of increase in atmospheric carbon dioxide. Through carbon isotope analysis, we can show that this carbon dioxide in the atmosphere is coming directly from our burning of fossil fuels, not from natural sources. We have satellites measuring the heat released from the planet and can actually see the atmosphere get warmer, and pinpoint its sources to human activities. The most crucial proof emerged only the past few years: climate models of the greenhouse effect predict that there should be warming in the stratosphere, but cooling in the troposphere, and that’s exactly what our space probes have measured. Finally, we can rule out any other culprits: solar heat has been decreasing since 1940, not increasing, and there are no measurable increases in cosmic radiation, methane, volcanic gases, or any other potential cause. Face it—it’s our problem.
4. As Oreskes and Conway demonstrated in their 2010 book Merchants of Doubt, and I expanded upon in my book Catastrophes!, the “doubt” about anthropogenic global warming was not some sort of minority opinion among real climate scientists. Instead, a number of leaked memos show that it was entirely a PR campaign cooked up by energy lobby (mostly oil and coal producers) and the right-wing and libertarian institutes (especially the Marshall Institute and Heartland Institute) to blunt the political forces that were taking anthropogenic global warming seriously. They resorted to the same tactics as other kinds of reality deniers, such as the Holocaust deniers or the creationists: citing studies out of context to mean the opposite of what was actually said (the whole “climategate” kerfuffle over their misreading of stolen emails); generating phony “lists of scientists who doubt” evolution or global warming (these lists are composed almost entirely of people with no academic credentials in climate change research or evolutionary biology, so their “dissent” is immaterial); taking small pieces of data out of context to deliberately misrepresent the actual record (for example, the claim that “climate has been cooling since 1998″ is based on a tiny downward wiggle from 1998-2001, while the overall trend is hotter, and the hottest global average temperatures on record have come from the past 3 years); pointing to small differences between labs or individual scientists that they can’t get their story straight (but as the 2007 IPCC report and the previous studies showed, the consensus is virtually unanimous among working climate scientists). Even more striking, the deniers of both evolution and climate change are largely overlapping audiences, now that it is virtually a creed among the GOP and Fox News, and creationist websites like the Discovery Institute site now feature as much climate denialism as they do evolution denialism. (Just last week Texas Gov. Rick Perry stridently topped all the other GOP presidental candidates in denying global warming, accusing scientists of cheating and exaggerating to make themselves rich. This kind of shoot-the-messenger demagoguery is laughable. Most research scientists I know made big sacrifices of many years in grad school to earn their degrees, only to receive a paltry academic’s salary which is much less than they should receive for so much education in comparison to lawyer, doctors—or politicians and oil geologists. None of the scientists I know are motivated primarily by money—they do it because they love their field of research, and want to find out what is happening with climate, not line their pockets).
All of this was grist for a lively discussion during the cruise seminars. Fortunately, we were able to point to some encouraging trends. The entire debate over global warming in the U.S. is largely a rear-guard action and irrelevant to where the political winds are blowing now. Most of the rest of the world’s nations accepts the reality. The fact that even Kyoto holdouts like China, India, and the U.S. agreed to the basic science of global warming in the 2009 Copenhagen climate summit is a big step forward. (Unfortunately, our political gridlock has also meant that other countries, especially China, are pushing hard to develop the next green technology, and leaving us behind). It is not just the liberals and environmentalists who are taking climate change seriously. Historically conservative institutions (big corporations, the insurance companies, emergency management agencies, the U.S. military, and even some oil companies) are already planning on how to deal with global warming. These organizations have no political axe to grind or party affiliation, but they must plan for a future that is clear to climate scientists and most people around the world, even if it is clouded in the U.S. by political ideology.
Some people may still try to deny scientific reality, but big businesses like oil and insurance, and conservative institutions like the military, cannot afford to be blinded or deluded by ideology. They must plan for the real world that we will be seeing in the next few decades. They do not want to be caught unprepared and harmed by global climatic change when it threatens their survival. Neither can we as a society.
- Oreskes, N. 2004. Beyond the Ivory Tower: The scientific consensus on climatic change. Science 306: 1686.
- Doran, P., and M. Kendall Zimmerman. 2009. Examining the scientific consensus on climatic change. EOS 90 (3): 22.
- Anderegg, W.R.L., Prall, J.W., Harold, J., and Schneider, S.H. 2010. Expert credibility on climate change. Proceedings of the National Academy of Sciences (USA) 107:12107–12109.
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