Being a scientist myself, it has been bugging me for quite some time how people who clearly have no clue of the scientific method, analytical thinking in general, or climate science in particular, are trying to weigh in on the debate about global warming. I do not mean to sound elitist, but this is not like choosing which curtains fit better with the bedroom carpet, a subject on which certainly everyone is entitled to an opinion. Science is different because science is not about uttering opinions and gut feelings but about finding facts and proving them. For most scientists it takes somewhere between 10-15 years of training (3 years for the BSc, another 1-2y for the MSc, 3-5y for the PhD, and how ever long it takes as a post-doc) before you finally get a permanent position and are allowed to lead major research projects. So if some guy with a 3-year undergraduate degree in economics – aka Donald Trump – feels like he needs to weigh in with statements like:
“[climate change is] an expensive hoax”, “a concept…created by and for the Chinese”, and pure “bullshit” – Donald Trump
- identify him as the tosser that he obviously is for saying things like this about an important subject he clearly knows absolutely nothing about, and, more importantly
- not elect him president of a country … duh!
What is the main argument?
One common argument by climate change deniers like Trump is what they call the “lacking consensus” in the scientific community. Many will remember this argument from a few decades back when the topic was not climate change but whether smoking causes cancer. Today, smoking is banned from most public places and tobacco companies are obliged to display unambiguous slogans often in combination with explicit images on their merchandise in order to warn people about what they are doing to themselves. Considering that the first study linking smoking with cancer dates from 1929 it has certainly taken a very long time and very many human casualties to get where we are today. Unfortunately, the casualties caused by global warming will be significantly higher if it takes us as long as it took with tobacco to overcome the profiteering and political misinformation. But for argument’s sake, let’s look at this claim about lacking consensus.
There are thousands of scientific articles that have been published on the topic of climate change. Most of them from experts, that is, people who are actual climate scientists, but of course you can also find articles on climate change and its causes published by members from, for instance, the social sciences, economics, or by law graduates. Now, in order to test this “lacking consensus” argument, some people looked at all those publications and divided them into two camps: those that argue that human activities are to blame for global warming and those who argued otherwise. Because even those “consensus” studies have become rather numerous by now, one recent study by Cook et al. (2016) aggregated all of these consensus studies into a single number. The result:
Now I am not sure what other issue has a 97% consensus among highly educated people but I think this is a pretty good number. Another finding that is interesting to look at is that the consensus increased with increasing expertise, that is to say, the more closely a scientist’s background was to climate science, the more likely they were in the consensus camp.
If you were a law or economics graduate, on the other hand, who had published an article debating the causes of climate change, you were less likely to be in the consensus camp. The fact that overall only 3% were in the denial camp, shows that the overwhelming majority of articles published on this topic is indeed written by absolute experts in the field which is reassuring. By only looking at publications from real experts, this consensus was also confirmed by Powell (2015) who found that:
So instead of a “lacking consensus” there is essentially a unanimous consensus on the issue, at least among those people who actually know what they are talking about.
Therefore, people who try to convince you that man-made causes of our warming climate are still open for debate are simply merchants of doubt who are fools at best, but criminals at worst, as they knowingly try to deceive the public in order to achieve some short-term personal/political/economic gain at the expense of our long term survival prospects as a species and the already rather imminent survival challenges faced by several countries (go look up Mauritius, Bangladesh, or the Netherlands on Wikipedia). Also see my post on the rise of demagogues for some more reading on the issue of misinformation in politics.
In this context, we would do well to remember the now infamous Frank Luntz U.S. White House memo on climate change. Apart from the rather shocking tone and level of cynicism and disrespect toward the general population, the document advises US conservative party members to
“continue to make the lack of scientific certainty a primary issue in the debate”, despite the fact that “[t]he scientific debate is closing [against us]” but “[t]here is still a window of opportunity to challenge the science.” He goes on to say that “[m]ost Americans want more information so that they can make an informed decision. It is our job to provide that information.” – Frank Luntz (advisor to the White House 2002)
Really? Your job? If anyone should be informing the public about the issue of climate change it should be science and not a politician. One word of advice: if some politicians try to sell you some information on climate change, don’t buy it, in particular if that politician is affiliated with a mainstream political party that is almost exclusively financed through corporate sponsorship.
Unfortunately, many people have bought into the misinformation because the compelling scientific facts and consensus among scientific experts is neither reflected in the media coverage nor in public opinion. This seems to be particularly true for the US where demagogues like Frank Luntz have done a first rate job in misleading the public:
All I can say to this is: choose your sources of information carefully, and evaluate the information they provide critically. You do not have to resort to the specialist scientific literature to inform yourself about climate change. Portals like Wikipedia can be a good source of information on such topics as they provide information in ways that can be understood by a non expert.
“But last summer was quite cool, so how can it possibly be global warming?”
Not so long ago, I was sitting on a plane to New Zealand and was chatting to my seat neighbour. When he found out that I was a scientist, he immediately needed to weigh in on the subject of climate change with something like this: “you know, the summer this year in my home town has not been that warm, so I don’t really believe in this whole global warming thing.”
I then wondered whether that same person would have been equally confident in flaunting his non-expert opinion if I introduced myself as a theoretical physicist studying black holes or string theory. In comparison to theoretical physics, climate science may appear much more accessible as we all experience weather (which some mistake for climate) on a daily basis and we therefore feel that our 20, 30, 40, or 50 years of life experience should account for something. This is probably why people like my seat neighbour feel that it’s okay if they weigh in, even if they do not possess any scientific training whatsoever, and their knowledge of what influences climate dynamics or causes global warming is equally limited as their knowledge of black holes or astrophysics.
So let me make this very clear: just because the summer in your back yard has been a bit cooler this year compared to the last, does not mean that it has been like this for everyone else on the planet. In addition, global warming does not mean that we cannot have a year that is a bit cooler because there is always the short term variability superimposed on the long term trend, but global warming is measured over long terms and those numbers do not leave any room for doubt. Nevertheless, I want to finish this post with a very short reminder of the main facts:
- Undergraduate physics tells us that CO2 can absorb long wave radiation (also kown as heat).
- In principle this is a good thing, as the mean temperature on earth without any CO2 in the upper atmosphere would be about -18°C.
- However, the concentration of CO2 has increased by almost 40% since pre-industrial times, commensurate with increased CO2 emissions by human activity.
- At the same time, temperatures have increased significantly, and rapidly.
- All climate models agree that the only way to limit the increase in temperature is to reduce our emissions of CO2.
We are currently witnessing one of the largest refugee crises with huge numbers of people on the move due to the worldwide increase in war and violence. Nevertheless, this will be but a taste of what is to come in terms of the number of displaced people, if we do not contain this threat posed by global warming. Rather than voting people like Donald Trump into power, we should be putting them into prison as their inaction and wilful misinformation will cost thousands if not millions of human lives.