Scott Adams, the creator of Dilbert, wrote today about how difficult it is for a non-expert to judge science and especially climate science. He argues that for a non-expert it is normally a good idea to follow the majority of scientists. I agree. Even as a scientist I do this for topics where I am not an expert and do not have to time to go into detail. You cannot live without placing trust and you should place your trust wisely.
While it is clear to Adams that a majority of scientists agree on the basics of climate change, Scott Adams worries that they could all be wrong. He lists the 6 signals that this could be the case below and sees them in climate science. If you get your framing from the mitigation sceptical movement and only read the replies to their nonsense you may easily get his impression. So I thought it would be good to reply. It would be better to first understand the scientific basis well before venturing into the wild.
The terms Global warming and climate change are both used for decadesScott Adams assertion: It seems to me that a majority of experts could be wrong whenever you have a pattern that looks like this:
1. A theory has been “adjusted” in the past to maintain the conclusion even though the data has changed. For example, “Global warming” evolved to “climate change” because the models didn’t show universal warming.
This is a meme spread by the mitigation sceptics that is not based on reality. From the beginning both terms were used. One hint is name of the Intergovernmental Panel on Climate Change, a global group of scientists who synthesise the state of climate research created in 1988.
The irony of this strange meme is that it were the PR guru's of the US Republicans who told their politicians to use the term "climate change" rather than "global warming", because "global warming" was more scary. The video below shows the historical use of both terms.
Global warming was called global warming because the global average temperature is warming, especially in the beginning there were still many regions were warming was not yet observed, while it was clear that the global average temperature was increasing. I use global warming if I want to emphasis the temperature change and climate change when I want to include all the other changes in the water cycle and circulation. These colleagues do the same and provide more history.
Talking about "adjusted", mitigation sceptics like to claim that temperature observations have been adjusted to show more warming. Truth is that the adjustments reduce global warming.
Climate models are not essential for basic understandingScott Adams assertion: 2. Prediction models are complicated. When things are complicated you have more room for error. Climate science models are complicated.
Yes, climate models are complicated. They synthesise a large part of our understanding of the climate system and thus play a large role in the synthesis of the IPCC. They are also the weakest part of climate science and thus a focus of the mitigation sceptical movement.
However, when it comes to the basics, climate model are not important. We know about the greenhouse effect for well over a century, long before we had any numerical climate models. That increasing the carbon dioxide concentration of the atmosphere leads to warming is clear, that this warming is amplified because warm air can contain more water, which is also a greenhouse effect is also clear without any complicated climate model. This is very simple physics.
The warming effect of carbon dioxide can also be observed in the deep past. There are many reasons why the climate changes, but without carbon dioxide we can, for example, not understand temperature swings of the past ice ages or why the Earth was able to escape from Snowball Earth at a time the sun was much cooler.
The main role of climate models is trying to find reasons to expect the climate to respond differently from its response in the past or whether there are mechanisms beyond the simply physics that are important. The average climate sensitivity from climate models is about the same as for all the other lines of evidence. Furthermore, climate models add regional detail, especially when in comes to precipitation, evaporation and storm. These are helpful to better plan adaptation and estimate the impacts and costs, but are not central for the main claim that there is a problem.
Model tuning not important for basic understandingScott Adams assertion: 3. The models require human judgement to decide how variables should be treated. This allows humans to “tune” the output to a desired end. This is the case with climate science models.
Yes, models are tuned. Mostly to get the state of the atmosphere right, the global maps of clouds and precipitation, for example. In the light of my answer to point 2, this is not important for the question whether climate change is real.
The consensus is a result of the evidenceScott Adams assertion: 4. There is a severe social or economic penalty for having the “wrong” opinion in the field. As I already said, I agree with the consensus of climate scientists because saying otherwise in public would be social and career suicide for me even as a cartoonist. Imagine how much worse the pressure would be if science was my career.
It is clearly not career suicide for a cartoonist. If you claim that you only accept the evidence because of social pressure, you are saying you do not really accept the evidence.
Scott Adams sounds as if he would like scientists to first freely pick a position and then only then look for evidence. In science it should go the other way around.
This seems to be the main argument and shows that Scott Adams knows more about office workers than about the scientific community. If science was your career and you would peddle the typical nonsense that comes from the mitigation sceptical movement that would be bad for your career. In science you have to back up your claims with evidence. Cherry picking and making rookie errors to get the result you would like to get are not helpful.
However, if you present credible evidence that something is different that is great, that is what you become scientist for. I have been very critical of the quality of climate data and our methods to remove data problems. Contrary to Adams' expectation this has helped my career. Thus I cannot complain how climatology treats real skeptics. On the contrary, a lot of people supported me.
Another climate scientist, Eric Steig, strongly criticized the IPPC. He wrote about his experience:
I was highly critical of IPCC AR4 Chapter 6, so much so that the [mitigation skeptical] Heartland Institute repeatedly quotes me as evidence that the IPCC is flawed. Indeed, I have been unable to find any other review as critical as mine. I know "because they told me" that my reviews annoyed many of my colleagues, including some of my [RealClimate] colleagues, but I have felt no pressure or backlash whatsover from it. Indeed, one of the Chapter 6 lead authors said “Eric, your criticism was really harsh, but helpful "thank you!"If you have the evidence there is nothing better than challenging the consensus. It is also the reason to become a scientist. As a scientist wrote on Slashdot:
Look, I'm a scientist. I know scientists. I know scientists at NOAA, NCAR, NIST, the Labs, in academia, in industry, at biotechs, at agri-science companies, at space exploration companies, and at oil and gas companies. I know conservative scientists, liberal scientists, agnostic scientists, religious scientists, and hedonistic scientists.
You know what motivates scientists? Science. And to a lesser extent, their ego. If someone doesn't love science, there's no way they can cut it as a scientist. There are no political or monetary rewards available to scientists in the same way they're available to lawyers and lobbyists.
Scientists consider and weigh all the evidenceScott Adams assertion: 5. There are so many variables that can be measured – and so many that can be ignored – that you can produce any result you want by choosing what to measure and what to ignore. Our measurement sensors do not cover all locations on earth, from the upper atmosphere to the bottom of the ocean, so we have the option to use the measurements that fit our predictions while discounting the rest.
No, a scientist cannot produce any result they "want" and an average scientist would want to do good science not get a certain result. The scientific mainstream is based on all the evidence we have. The mitigation sceptical movement behaves in the way Scott Adams expects and likes to cherry pick and mistreat data to get the results they want.
Arguments from the other side only look credibleScott Adams assertion: 6. The argument from the other side looks disturbingly credible.
I do not know which arguments Adams is talking about, but the typical nonsense on WUWT, Breitbart, Daily Mail % Co. is made to look credible on the surface. But put on your thinking cap and it crumbles. At least check the sources. That reveals most of the problems very quickly.
For a scientist it is generally clear which arguments are valid, but it is a real problem that to the public even the most utter nonsense may look "disturbingly credible". To help the public assess the credibility of claims and sources several groups are active.
Most of these zombie myths are debunked on RealClimate or Skeptical Science. If it is a recent WUWT post and you do not mind some snark you can often find a rebuttal the next day on HotWhopper. Media articles are regularly reviewed by Climate Feedback, a group of climate scientists, including me. They can only review a small portion of the articles, but it should be enough to determine which of the "sides" is "credible". If you claim you are sceptical, do use these resources and look at all sides of the argument.
While political nonsense can be made to look credible, the truth is often complicated and sometimes difficult to convey. There is a big difference between qualified critique and uninformed nonsense. Valuing the strength of the evidence is part of the scientific culture. My critique of the quality of climate data is part of that. There are also real scientific problems in understanding changes of clouds, as well as the land and vegetation. These are important for how much the Earth will respond. Although the largest source of uncertainty is how much we will do to stop the problem.
There are real scientific problems when it comes to assessing the impacts of climate change. That often requires local or regional information, which is a lot more difficult than the global average. Many impacts will come from changes in severe weather, which are by definition rare and thus hard to study. For many impacts we need to know several changes at the same time. For droughts precipitation, temperature, humidity or the air and of the soil, the insolation are all important. Getting them all right is hard.
How humans and societies will respond to the challenges posed by climate change is an even more difficult problem and beyond the realm of natural science. Not only the benefits, but also the costs of reducing greenhouse gas emissions are hard to predict. That would require predicting future technological, economic and social development.
When it comes to how big climate change will be and its impacts I am sure we will see some surprises. What I do not understand is why some are arguing that this uncertainty is a reason to wait and see. The surprises will not only be nice, they will also be bad and all over increase the risks of climate change and make the case to speed up solving this solvable problem stronger.
Related readingOlder post by a Dutch colleague on Adams' main problem: Who to believe?
How climatology treats sceptics
Whats in a Name? Global Warming vs. Climate Change
Fans of Judith Curry: the uncertainty monster is not your friend
Video medal lecture Richard B. Alley at AGU: The biggest control knob: Carbon Dioxide in Earth's climate history
Just the facts, homogenization adjustments reduce global warming
Climate model ensembles of opportunity and tuning
Journalist Potholer makes excellent videos on climate change and true scepticism: Climate change explained, and the myths debunked.
* Photo Arctic Sea Ice by NASA Goddard Space Flight Center used under a Creative Commons Attribution 2.0 Generic (CC BY 2.0) license.
* Cloud photo by Bill Dickinson used under a Creative Commons Attribution-NonCommercial-NoDerivs 2.0 Generic (CC BY-NC-ND 2.0) license.