Nov 06 2017

US Government Report Affirms Climate Change

climate changeThe U.S. Global Change Research Program Climate Science Special Report was recently published, and its conclusions are crystal clear:

 This assessment concludes, based on extensive evidence, that it is extremely likely that human activities, especially emissions of greenhouse gases, are the dominant cause of the observed warming since the mid-20th century. For the warming over the last century, there is no convincing alternative explanation supported by the extent of the observational evidence.

That conclusion is nothing new to those following the science of climate change for the last couple decades or so. The more this question is studied, the more data is gathered, the firmer the conclusion becomes – the planet is warming due to human release of greenhouse gases, such as CO2. There are error bars on how much warming, and the exact effects are hard to predict, but that’s it. The probable range of warming and effects are not good, however. It will be bad, the only real debate is about how bad and how fast.

The conclusions of the report, therefore, at least scientifically, are not surprising. It was, however, politically surprising. The special report began in 2015, under Obama. Because of Trump’s stated position that global warming is a Chinese hoax, and his appointment of many global warming deniers to key positions, it was feared that his administration would slow or frustrate the publication of this report.

However, according to the NYT, Trump himself was simply unaware of the report. Further, the fate of the report was largely in the hands of those amenable to following the science, rather than putting a huge political thumb on the scale. As a result the report was not hampered or altered. It was approved by 13 agencies who reviewed its findings.

The reports adds to the consensus of consensus that global warming is real and human-caused. What I mean by the “consensus of consensus” is that multiple reviews by expert panels have come to the same conclusion about the consensus of scientific evidence. There are only fringe outliers, as there are with most scientific questions (no matter how strong the consensus).

It remains to be seen how Trump himself or his administration will respond to the report. However, the global warming denier community has already dismissed it as the result of “Obama holdovers.”

There is good reason to be pessimistic about the effects this report will have on public opinion. While it does seem that public opinion is slowly moving in the direction of accepting the science of global warming, there is a strong ideological influence on what people believe. A study from March 2017 surveyed 9,500 people over several years and found that the strongest predictor of their views on climate change was their party affiliation.

In other words, you could predict with a high level of accuracy someone’s attitudes toward climate change if you knew only their party affiliation. This effect was strengthened the more they paid attention to the news. Therefore consuming information itself did not move people toward the scientific consensus, just toward their party line.

I do want to point out, because this point is often missed, that this motivated reasoning phenomenon is not universal but appears to be in proportion to the degree to which issues are strongly ideological and tied to tribal affiliation.

Of course, in an ideal world this would not be the case. Science should speak for itself, and should inform politics but not be determined by it. Party affiliation should have nothing to do with the scientific consensus on a scientific question. This highlights the importance of separating science from ideology, and the need for better education in philosophy and critical thinking. This is a failure of thinking clearly and scientific literacy.

Both sides, of course, will think that they are the one’s who are in line with logic and evidence and the other side is succumbing to political ideology. This does not mean that the issue is necessarily symmetrical – that both sides are wrong. Sometimes the science happens to be in line with our ideology. In those cases the accuracy of your views on the science is almost incidental, or at least it does not provide convincing evidence that you will accept scientific conclusions regardless of their ideological implications.

What is convincing evidence is when someone accepts a scientific consensus on a question even when it is inconvenient to their ideology or party affiliation. Again, I am not saying there is absolute symmetry, but liberals, for example, should not be smug about their acceptance of the scientific consensus on climate change unless they also accept the scientific consensus on genetically modified food, organic farming, vaccines, alternative medicine, and nuclear energy.

Part of the problem is motivated reasoning. Part of the problem (perhaps a growing part) is the echochamber effect. But also scientific literacy plays a huge role, and here I am not just talking about factual scientific knowledge but the ability to evaluate scientific research and opinions, to determine what the consensus of scientific opinion is and how solid it is. This means not citing retracted papers, fringe opinions, or preliminary studies as if they were definitive, for example.

And of course critical thinking is essential – knowing how to avoid common pitfalls such as logical fallacies and conspiracy thinking.

But the key concept to understand with regard to the relationship between scientific questions and ideology is this – don’t expect or demand that the science will always be maximally convenient to your political views. Understand, by chance alone, it won’t be. You should strive to be most suspicious of scientific claims when they do seem to support your political ideology, because of the motivation to accept such conclusions uncritically. Further, structure your ideological value-based opinions in such a way that they can accommodate whatever conclusions science comes to.

In other words, if you are pro-environment, then support whatever policies are science-based, rather than choose the scientific conclusions that are in line with environmentalist ideology. If you value the free market, then propose rational free-market solutions to the problems that the scientific evidence says we face. Don’t deny the science to make it more convenient for a free-market ideology.

This is where philosophical literacy comes in – understanding the difference between value-based opinions and empirical questions of fact. I also think it is critical to value the truth as part of your ideology. Following a valid logical process needs to be highly valued in itself, and not, therefore, easily subverted to other values.

Otherwise you end up denying a strong scientific consensus because the pundits on news outlets that make you feel good about your political affiliation tell you it’s a hoax.

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