Climate science as a social process

I came across a paper that might be of interest to regular readers of this blog. It’s by Hans von Storch and is a Brief communication: Climate science as a social process – history, climatic determinism, Mertonian norms and post-normality. Before I start, there is some background. A few years ago, I had a discussion with the author in the comments of a Die Klimazweibel blog post. In one response, they stated: In other words: physicists (and other natural scientists), back into your baracks! The author of the post on which we were commenting also once suggested that [t]here is an eerie similarity between race science and climate science. In my view, some rather strange views about physical/climate science.

To be honest, I’m finding it tricky to develop a coherent comment on the paper; I found it all rather confusing. Maybe some commenters can develop more coherent responses, but I thought I would comment on some general themes.

  • Post-normal science: The paper suggests that climate science is in a “post-normal” phase. Post-normal science is, supposedly, when “facts [are] uncertain, values in dispute, stakes high and decisions urgent“. I think there are a number of issues with this. Firstly, I don’t see much difference between climate science and many other areas of “normal” science. Secondly, how does this account for attempts to manufacture uncertainty? Given the definition of post-normal science, one way to undermine inconvenient results from “normal” science is to argue that the “facts” are more uncertain than they actually are and, hence, that this “normal” science is actually “post-normal”. Finally, defining something as post-normal is meant to help when “facts [are] uncertain, values in dispute, stakes high and decisions urgent” but, despite numerous discussions with one of developers of this idea, I’ve no idea how this is actually meant to work.
  • Mertonian norms: The paper also suggests that climate science has been taken over by physical scientists who have imposed a set of norms. These Mertonian norms are Communalism, Universalism, Disinteredness, and Organized Skepticism. They were actually first described by a sociologist, not by a physicist. Although I think most physical scientists would regard them as reasonable ideals, I’d be surprised if most were aware of the term Mertonian norms, and I doubt that most would only regard something as scientific if it satisfies them. Our confidence in something may grow the more it satifies these norms, but they don’t define what is scientific. I’d also argue that these are reasonable norms for any area of research, not just the physical sciences.
  • Climate determinism: I do think this is something that is worth being aware of. We do have to be careful of suggesting that the climate, or some change in the climate, will determine some societal response. Clearly, how society responds will depend on many factors, and can be influenced by how resilient, and prepared, a particular society happens to be. However, physical scientists do tend to think in terms of all else being equal. This doesn’t mean that they think all else will be equal, but it can be a useful baseline against which to judge what might need to be done to deal with the impact of some change. So, I do sometimes think that some confuse climate determinism with suggestions that climate change could be severely disruptive unless we take action to minimise the impact.

This paper also reminds me of another paper by Reiner Grundmann which essentially suggested that there should be less science, more social science. My issue with these type of arguments is that they seem to misrepresent how research works in practice. When topics become of interest, more and more scholars will start to study it. If you don’t like the resulting focus, or the dominance of some scholars, the ideal would be to do the scholarship that you think is missing, and convince people of its significance. Suggesting that the problem is these other scholars who have somehow taken over, just seems churlish and – in my view – rather unconvincing.


Brief communication: Climate science as a social process – history, climatic determinism, Mertonian norms and post-normality – paper by Hans von Storch.
Climate change as a wicked social problem – Die Klimazweibel blog post by Reiner Grundmann.
Mertonian norms – my post about Mertonian norms.
Less science, more social science – my post about Reiner Grundmann’s paper.

Posted in Climate change, physicists, Research, Resilience, Scientists, The philosophy of science, The scientific method, Uncategorized | Tagged , , , , , , | 63 Comments

The Escalator

One of the most well-known graphics from Skeptical Science is the escalator. It illustrates how contrarians tend to cherry-pick short time intervals so as to argue that there’s been no warming, while “realists” recognise the reality of long-term warming.

A classic example of the former was the so-called pause, which was based on claims that there had been no warming since the strong El Nino in 1998. Of course, as illustrated by the escalator, there really hadn’t been a pause in global warming.

The Skeptical Science escalator is, however, now slightly dated, with the latest version ending in 2015. I also noticed that Robert Rohde had presented an updated version on Twitter, which he called the staircase of denial.

This motivated me to produce an updated version for Skeptical Science, which I’ve also posted below.

Posted in Global warming | Tagged , , , | 93 Comments

True Contrarians

I like contrarians, and consider contrarian a term of endearment. If we believe the investment lore, only contrarian traders achieve success. The myth rings true: to beat the market, one must go against it. To win, contrarians need to believe in their own edge over otters. Which might explain why contrarians lionize individualism. They need to go their own way. Sometimes it works for all the good reasons.

Chace Barber drove logging trucks since the beginnings, to pay for his U. Big, heavily loaded trucks riding up and down mountain forests. Frustrated by the job offers from econ shops, he bought a 1969 Kenworth and started a trucking gig. It failed, after which he started Edison Motors {1}. His company now builds custom electric and hybrid trucks.

I see two main ingredients in his secret sauce. First, that parts from old trucks are all standardized, and thus cheap. During the Cold War the US Army asked contractors to build vehicles with interchangeable parts. This is critical for logging trucks, because when they break, drivers need to fix them on their own in the middle of nowhere. Second, he wants to exploit a known physical effect {2}:

This Physics Professor Recharges Electric Trucks as they Ride with this ONE WEIRD TRICK!

Hard not to root for Chace. He looks and sounds like a true contrarian. The same could have been said of Porter Stansberry, for different reasons, at least at first. When Porter talks about recession, distressed debt or crypto, he sounds like a run of the mill value investor {3}. But when he goes full Climateball mode, we see that going one’s way can reach epic hubris.

Take his Two Men project. It features Larry Fink, from Blackrock, and Michael Bloomberg. Two powerful men, incidentally of Jewish lineages. Let me spare you the financial and mediatic details he offers about the Great Reset of Western Civilization. You already heard a similar tune.

On the Climateball side, many Bingo squares get triggered, among them But Alarmism. But 12 Years, But Modulz, But Data, But RCPs, and But The Poor. You may never guess his smoking gun: Junior’s conspiracy at Forbes’, a company owned in majority by Integrated Whale Media {4}.

So Porter’s recipe reads like this: (1) create websites with fake documentaries with well-known Climateball tropes; (2) after red meat priming, ask Freedom Fighters to subscribe to a newsletter and buy reports on hand picked small cap stocks, which he presumably already owns; (3) profit.

Hard for me not to root for Chace. Hard for me not to dismiss Porter as another crank. Yet Chace’s path carries more risks. Many of Porter’s calls were tremendously profitable over the years. Investing in gas indeed is a no brainer for anyone who followed the energy markets recently. So it’s not exactly a scam.

Why the Climateball talking points, then? Why rant about gas stoves? Why persist in trying to bend hard facts known for decades? As Sage Welch suggests, to resurrect this concern can only help those who wish to bring climate to the forefront.

All and all, we need better contrarians. True contrarians. No time to wait for our milquetoast troglodytes. Become one yourself. Be a contrarian’s contrarian. ABC – Always Be Contrarian.


{1} Chace raises money over Tik Tok. He only accepts 1K investments. Most of his funding comes from truckers who can recognize the value proposition behind the craftsmanship.

{2} Levin’s channel is pure awesomeness. It belongs in a space shuttle for aliens not to despair on us.

{3} Value investors tend to be contrarian. Think Warren Buffet, Peter Lynch, Carl Icahn.

{4} Oh, Junior. You silly you.

Posted in ClimateBall, ClimateBall Bingo | Tagged , , , , , , | 18 Comments

The Gulf Stream

Quite often in the media there will be articles claiming that global warming could cause the Gulf Stream to shutdown, or collapse. This is technically not correct, which is explained really nicely, in the video below, by Sabine Hossenfelder.

Essentially, the Gulf Stream is driven by the rotation of the Earth, so simply cannot shutdown. What the news reports are typically referring to is the Atlantic Meriodional Overturning Circulation (AMOC), which is a complex circulation network that carries warm water from the equator towards the north pole, and cold water from the pole back towards the equator. The concern is that as the ice at the pole melts, the water becomes less salty and less dense, making it harder for it to sink and drive the AMOC.

However, as the video below highlights, even if the Gulf Stream can’t shutdown, the AMOC does push it to higher latitudes. Hence, a slowdown of the AMOC could move the Gulf Stream to the south and could cool parts of Europe by up to 5oC. So, even if the Gulf Stream can’t shutdown, it can still be infuenced by global warming.

Posted in Climate change, Global warming, Science, Severe Events | Tagged , , , | 32 Comments

Plausible scenarios

New Scientist has a recent article about [t]he worst-case climate scenarios are no longer plausible today. This is a topic that has been covered here before, and is partly motivated by a paper discussed in this post.

The basic premise in the article is that global warming of between 4oC and 5oC is no longer a real risk. The problem is that even if the wost-case emission scenario is no longer plausible, uncertainties in climate sensitivity and carbon cycle feedbacks means that we still can’t rule out >4oC of global warming.

The article also suggests that these scenarios date back to 2014, when they were published by the IPCC. As this Skeptical Science post describes, their development actually started in 2007. Also, the concentration/forcing pathways and socioeconomic scenarios were actually developed in parallel, rather than the concentration/forcing pathways following from a set of socioeconomically motivated emission pathways.

The article also suggests that the worst-case scenario became to be known as the business as usual (BAU) pathway. Probably an unfortunate choice of terminology, but this was actually what was used to describe it in the paper that presented it in 2011. Even the 2014 IPCC report (AR5) had a glossary entry that said that BAU has “fallen out of favour because the idea of ‘business-as-usual’ in century-long socioeconomic projections is hard to fathom.The latest IPCC report (AR6) also tended to use Global Warming Levels (GWLs) rather than simply using the scenarios (i.e., it reported on the impact of different levels of warming, rather than simply the impact of following different concentration pathways).

So, in my view, there’s a lot nuance that the article glossed over, or ignored, and many researchers are already taking note of these criticisms about scenario use.

I wanted to finish by commenting on the following. The article suggests that:

This puts climate scientists on the horns of a dilemma. Do they admit BAU was never really that plausible and risk deniers saying “we told you so” and spreading further muck about climate modelling? Or do they keep pushing BAU and risk it becoming obvious they are hawking a straw man, opening the door to… deniers saying “we told you so”?

Climate deniers may well say “we told you so“, but this isn’t what they’ve been claiming. Climate deniers haven’t really been suggesting that high-emission pathways are implausible, they’ve been claiming that it wouldn’t matter if we did follow such a pathway. They either deny that climate change is driven by human emissions, or deny that this carries any risks.

Also, despite the unfortunate use of BAU, the high emission pathway was always a pathway that we were unlikely to follow. If it had been, we would probably have included an even higher emission pathway. We want scientists to consider worst-case scenarios which, in most cases, we’d hope would not materialise. If scientists are expected to acknowledge some kind of error when it becomes clear that this is the case, then we run the risk of discouraging scientists from considering them in the first place.

Finally, climate scientists are – typically – not experts in energy systems, policy, or economics. They typically use scenarios that are developed by other scholars to try and understand how the climate will change under different possible future pathways and the potential impact of these changes.

In a sense it’s unfortunate that this isn’t simply being presented as an evolution of our understanding of the plausibility of these scenarios, rather than something that implies some kind of mistake on the behalf of those who use them. Of course, given some of the prominent people who are promoting this narrative, this is hardly a surprise.


The worst-case climate scenarios are no longer plausible today – New Scientist article.
RCP8.5 – Posts discussing the high-emission pathway, RCP8.5.
Scenarios – Posts about scenarios.
Plausible emission scenarios – post about a paper discussing plausible emission scenarios.
The Beginner’s Guide to Representative Concentration Pathways – Skeptical Science post about the RCPs.
RCP 8.5—A scenario of comparatively high greenhouse gas emissions – Riahi et al. (2011).
AR5 Glossary – highlighting how BAU has gone out of favour.
AR6 Technical Summary – discusses the use of Global Warming Levels (GWLs).

Posted in Climate change, ClimateBall, ClimateBall Bingo, economics, Scientists, The scientific method | Tagged , , , , | 242 Comments

Some more about Hansen et al.

I thought I would expand a bit on my previous post about the recent Hansen et al. paper. Something I did like is that the paper highlighted that there is no known paleoclimate analogues for the current anthropogenic forcing pathway. Humans are producing a substantial perturbation to a complex, non-linear system. Even though we have a good understanding of how the system might respond to such a perturbation, we shouldn’t rule out the possibility of surprises.

Additionally, the paper seems to be making a few key points. Firstly, it’s arguing that equilibrium climate sensitivity (ECS) is probably ~4oC, rather than the more standard best estimate of ~3oC. It’s also highlighting that the greenhouse gas (GHG) forcing is already 4 Wm-2, equivalent to a doubling of atmospheric CO2. So, the fast-feedback equilibrium warming (ECS) for today’s GHG forcing is already 4oC. Furthermore, it’s arguing that this implies a relatively large aerosol forcing that is currently masking about ~1oC of warming, implying a large amount of warming in the pipeline if aerosol emissions are substantially reduced.

Although the above arguments could well be correct, there are some other factors to consider. Even though todays’ GHG forcing is indeed probably around 4 Wm-2, it’s a combination of a number of different GHG species. The dominant one is CO2, but methane and some other species, contribute about one-third of this forcing. These species have relatively short atmospheric lifetimes. Hence, if human emissions of these species were also to substantially reduce, this would counteract some of the warming that would result if we were to substantially reduce aerosol emissions, although the timescales wouldn’t be quite the same.

Also, even though CO2 has a long atmospheric lifetime, this doesn’t mean that all the CO2 that has been emitted will remain in the atmosphere for a very long time, it just means that a significant fraction of what has been emitted will remain in the atmosphere for a very long time. So, if CO2 emission go to zero, the CO2 forcing will also decrease slightly. This is why the best estimate for the zero emission committment (how much further warming there will be if emissions go to zero) is very close to zero. In other words, the warming that has been locked in due to emissions to date is very close to the amount of warming that has occured to date.

Essentially, what this implies is that the warming in the pipeline depends mostly on future emissions and isn’t locked in due to past emissions. There’s, of course, no problem with estimating constant forcing/concentration warming committments, but maintaining a constant forcing/concentration does require continued emissions, so I do think it’s worth making clear that future warming depends mostly on future emissions, rather than being locked in due to past emissions. It is still possible to influence future warming, even if it will be very challenging to do so.

Posted in Climate change, Climate sensitivity, Global warming, Research | Tagged , , , | 15 Comments

Hansen’s 10C

A recent comment asked about James Hansen’s recent paper in which it is claimed that equilibrium global warming for today’s GHG level is 10°C. I’ve finally had a chance to look at it and I think I understand what is being suggested.

One suggestion in the paper is that the GHG forcing today is already 4 Wm-2, which is equivalent to a doubling of atmospheric CO2. It also argues that the aerosol forcing is large enough that this implies an equilibrium climate sensitivity (ECS) of 4oC. This is somewhat higher than the typical best estimate of 3oC, but within the likely range (2oC – 4.5oC).

The paper then considers the glacial cycles and argues that an ECS of 4oC is consistent with the glacial cycles, given global temperature changes of 6oC and total changes of radiative forcing (ice sheets plus GHGs) of 6 Wm-2.

The paper then argues that if the GHG forcing is 2.5Wm-2, this implies an equilibrium response to the GHG forcing of 2.4 Wm-2/oC, giving an equilibrium temperature change to a 4 Wm-2 GHG forcing of 10oC.

As I understand it, the problem with this is explained in this Realclimate post. The glacial cycles are driven by Milankovitch cycles (orbital variations) that don’t, by themselves, have a big impact on global temperatures, but can have large regional impacts that influence ice sheets. Changes to the ice sheets can influence temperatures, which can then change atmospheric GHG concentrations, which then also influence temperatures, and then ice sheets, etc.

Hence, these are coupled in a complex way. If you want to estimate the ECS, you can combine the longer-term changes (GHG concentrations, ice sheets, etc) into a single forcing and you get an ECS of around 3oC. To determine the response to the GHGs alone would require separating the influence of the orbital variations and GHGs on the ice sheets, which isn’t straightforward.

It will also depend on the climate state; if there are large ice sheets the response will probably be larger than when the ice sheets are much smaller, as they are today. So, I don’t think it’s correct to claim that equilibrium global warming for today’s GHG level is 10°C. There are a few other comments I could make about the paper, but since I’m trying to keep these posts short, I’ll stop there.

Posted in Climate sensitivity, Research, Scientists | Tagged , , , , | 70 Comments

Approximate net zero

Since I have a few free moments, I thought I would briefly highlight a paper by Jenkins et al. on [t]he Multi-Decadal Response to Net Zero CO2 Emissions and Implications for Emissions Policy. Recent IPCC reports have highlighted that limiting human-caused warming will require getting human emissions to (net) zero. What this paper suggests is that it might be better to aim for approximately net zero.

The analysis in the paper suggests that positive emissions of 2.2GtCO2/yr might be consistent with halting anthropgenic warming on multi-decadal timescales. The 95% range, though, is from -7.3GtCO2/yr to +6.2GtCO2/yr, so it could be higher, or it could require net-negative emissions. As far as I can see, this is broadly consistent with earlier work on the zero emission commitment, which suggested that the best estimate was that zero emissions would stabilise human-caused warming, but that it could also lead to some continued warming, or some cooling.

Personally, I quite like the suggestion of thinking in terms of approximate net zero. If we can reduce human emissions by ~90% (which is what would be required to get to ~2.2GtCO2/yr) then even if it doesn’t quite stabilise human-caused warming, it should significantly reduce the rate of warming. It woiuld give us some time to work out if emissions need to be reduced further, and if we would need to implement significant amounts of negative emissions.

Of course, it’s still not going to be easy to reduce emissions by ~90%, which is another reason why I quite like the idea of thinking in terms of approximate net zero; let’s try and get close before worrying about whether or not it has to be exactly zero, or negative.

Posted in Climate sensitivity, Policy, Research | Tagged , , , | 41 Comments

Bring back blogging

I came across a short article arguing that we should bring back personal blogging. The basic suggestion is that, for example, Twitter is failing and that personal blogs allow us to have more control over the platforms that we’re using.

I have certainly felt that the days of blogs are over and maybe it is now too late to go back to the days when blogs were prominent and popular.

However, the article has motivated me to try and blog more regularly. I may not succeed, but my intention is to try and write posts a bit more often, even if they are short and dull.

There are some issues that I do often think about and maybe I should try and use this blog to articulate my thoughts. I’ve become more and more interested in how we identify, and counter, misinformation. Similarly, I’ve become increasingly interested in the role of science in society, and it is a topic I’d like to explore more.

One factor, though, is that I’m finding myself more and more frustated with the tendency to have strong definitive views about topics that are complex and are probably more nuanced than many commenters are willing to acknowledge. If I manage to avoid doing this myself, this may make my posts rather convoluted and uncertain. However, maybe expressing my views will help me to clarify them, even if it doesn’t help anyone else.

Posted in Philosophy for Bloggers, Photography | Tagged , , | 42 Comments

2022: A year in review

I normally try to write a summary of some of the blog posts I’ve written during the year, and would typically highlight a few posts from each month. However, I’ve written so little this year, that I thought I would just highlight a few posts that I either thought were interesting, or that generated a fair amount of interest. I’ve also spent most of the day cooking, as we have guest coming for New Year’s eve. I’m already tired and the night is still young.

In January I highlighted a paper on the tragedy of climate change science, which I thought was interesting but wrong. Didn’t write much of interest in February, but I did write a post in March about ignoring the economists, that generated some interesting discussion, with some unsurprising comments.

In April I tried to explain the Greenhouse Effect again. Pointless if you’re trying to convince those that it doesn’t exist, but still an interesting thing to try and explain. I May I wrote about the science-society interface, and about a paper on World Atmospheric CO2 to which we’d written a response.

June had quite an active post about the hot-model problem, while July had a post about limits to growth. August had an active post on the importance of science communication and September had a post about the role of mathematical modelling.

October had a post about a cherry-picked analysis not demonstrating that we’re not in a climate crisis, which I had written for Skeptical Science and the cross-posted here. In November I discussed a podcast that had Andy Revkin and Bjorn Lomborg as guest, while December saw the unfortunate announcement of Victor Venema’s death.

Although I didn’t write many posts this year, the comment threads were more active than I had appreciated. Thanks to all of those who contributed. A happy New Year and a good 2023 to everyone. Now I need to have a short break before our guests arrive.

Posted in Uncategorized | Tagged , , | 42 Comments