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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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I've always been drawn to important problems that at the foundations of society - problems that are important, solvable and neglected. I'm also interested in questions of truth - how do we know what is true and what is false?

Climate change is an odd topic for me because it's important and solvable, but not really neglected or foundational. When I encountered climate science denial, on the other hand, it really touched upon my interest in truth. It challenged me to figure out how I could be sure whether I was right about climate science when dismissives were telling me with such absolute, unwavering confidence that I was wrong; it challenged me to puzzle over the question of what caused them think differently (and being unemployed, well, I had enough time to figure some of that out.) After spending a lot of time contributing to discussions on Denial101x/SkS, I was invited to join the all-volunteer team at SkS.

I am a software engineer by trade, and I aspire toward effective altruism and rationalism. My interests include science & technology, communication, big picture thinking, utilitarian consequentialismprogramming language designinternational auxiliary languages, electoral reform, corruption reform, nuclear reactors, and, of course, climate science. I've never been a real scientist, but at least I've spent some time watching the sausage being made.


Recent blog posts

Climate Science Denial Explained: The Denial Personality

Posted on 24 April 2018 by DPiepgrass

Continued from Part 2

When it comes to pseudo-skeptic behavior and motives, I'm no expert, but I'd like to share my sense of the kinds of behavior they use based on my debates with them. I'm sure frequent readers of SkS have their own impressions and I'd be interested in hearing about them.

They come in many flavors, but they tend to have some attributes in common. The core characteristic I noticed in debates was this: they will not engage with facts they don’t like.

If you make a weak argument (or if they misunderstand your argument), they will attack it relentlessly. But if you make a clear case that their reasoning is fallacious, or give them data they can't explain away, they will not engage. They simply ignore it, as though you had said nothing at all. Instead they will change the subject. I suppose how it works is, their brains contain a mental model in the form of a network of interconnected facts, myths and fallacies. They can let go of one or two fallacies temporarily, because the network has many more myths ready to compensate for the loss of one or two. But if you get too close to demolishing their core belief, they must ignore you to protect it,  like a Doctor Who perception filter.

Perhaps the key is that learning takes energy and deliberate effort, while ignoring is easy. If they make an effort to understand what you're saying, they risk overturning their own beliefs. Why should they bother? Their goal is to convince you, not to let you convince them. So they ignore you and push their narrative. If you do debate a pseudo-skeptic (and you shouldn’t until you spend some time studying the science and the myths), you’ll have to watch closely for the key arguments they have ignored, call them out on those, and spend little or no effort on the other points. It’s probably a bad habit that I tend to spend a lot of time doing research and write long responses; the longer it is, the easier it becomes to ignore you. Don’t waste your time. (Peter Hadfield suggests an easier approach, have a look.)

Here are some other characteristics I noticed:



Climate Science Denial Explained: Tactics of Denial

Posted on 17 April 2018 by DPiepgrass

Continued from Part 1

What they decline to understand

Thousands of climate scientists are working on all kinds of interesting subjects, from glaciology to oceanography to ecology to atmospheric physics. Some pseudo-skeptics don't understand that and seem to have no inkling of what climate scientists actually do.

Others, however, do understand that there's a large and sometimes-maybe-legitimate scientific endeavor going on, and they are happy to learn about some of that stuff, as long as they don't have to accept that human emissions cause warming.

While the land (red) has warmed faster than the ocean surface (blue), sea surface temperatures have the most impact on the global average because oceans cover 71% of earth’s surface. If global warming were caused by internal variability in the oceans (in other words, if the ocean surface warmed up because less cold deep water were being exchanged with it), then sea surfaces should warm as fast as the land. And if global warming were caused by the sun, days would warm faster than nights; in fact the opposite is true. Besides, solar output is measurable and has been decreasing. It is likely that warming in the 1920s and 1930s was caused largely by internal variability, and cooling in the 1950s, 60s and 70s has been attributed largely to internal variability plus aerosol emissions that happened before environmental regulations were introduced to reduce smog. Unlike CO2, aerosols disappear quickly from the atmosphere when emissions stop. So as our air got cleaner, the effect of CO2 became dominant.

Other things they're reluctant to accept include "global warming is dangerous" and "the problem can be solved" (and if you ask me, it isn't even that hard anymore).

The 5 characteristics

Whether the topic is climate change, lung cancer’s link to smoking, vaccines & autism, AIDS or MSG, denial of scientific findings relies on a set of techniques that can be summed up by the acronym FLICC:



Climate Science Denial Explained

Posted on 11 April 2018 by DPiepgrass

Lonnie Thompson, a climate scientist, was told by his doctor that he needed a heart transplant.

He denied it. “You’re crazy! I’ve been climbing the highest mountains in the world for…” he paused, mentally counted the decades.

Lonnie loved his job. He hiked up to mountain glaciers at 20,000 feet, to retrieve ice cores with the help of a solar-powered drill. He felt fine — it’s just asthma, he told himself — and as long as he needed a heart transplant, he wouldn’t be allowed to go on any more expeditions. Logically, then, his heart must be fine.

He fought his doctor for two years, and kept going on expeditions. Then while drilling in the Alps in 2011, he couldn’t get up from his tent. He couldn’t breathe. Luckily he was able to go down from the mountain, and return to the U.S. where he was admitted to an emergency room, and put on a heart pump



How could global warming accelerate if CO2 is 'logarithmic'?

Posted on 28 March 2018 by DPiepgrass

After publishing my experiences talking to science 'dismissives' (or 'skeptics', or whatever you'd like to call them) and then participating in the excellent Denial101x course, I was invited to join the volunteer team at SkepticalScience last year.

But before all that, one of the dismissives drew my attention to a climate science paradox:

  1. Scientists agree that the greenhouse effect is approximately logarithmic — which means that as we add more CO2 to the atmosphere, the effect of extra CO2 decreases.
  2. However, the IPCC projects that if we don't take steps to reduce our emissions, global warming won't just get worse, it will speed up:

IPCC AR5 warming projections

Figure 1: From IPCC AR5 synthesis report, page 11

How could both facts be true, I wondered? At the time I turned to "Ask A Climate Scientist" on Facebook and got a response from Steve Sherwood, an atmospheric scientist and one of the hundreds of IPCC report authors. I thought my first post here at SkS would be a good opportunity to share what I learned.



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