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Shellenberger’s op-ad

Filed under: — group @ 9 July 2020

Guest commentary by Michael Tobis

This is a deep dive into the form and substance of Michael Shellenberger’s promotion for his new book “Apocalypse Never”. Shorter version? It should be read as a sales pitch to a certain demographic rather than a genuine apology.

Michael Shellenberger appears to have a talent for self-promotion. His book, provocatively entitled “Apocalypse Never” appears to be garnering considerable attention. What does he mean by that title? Does it mean we should do whatever we can to avoid an apocalypse? Does it mean that no apocalypse is possible in the foreseeable future? For those of us who haven’t yet read the book (now available on Kindle), Shellenberger provides an unusual article (at first posted on Forbes, then at Quillette and the front page of the Australian) which appears less a summary than a sales pitch, an “op-ad” as one Twitter wag put it.

It’s called “On Behalf Of Environmentalists, I Apologize For The Climate Scare”. In short, Shellenberger lands clearly on the naysayer soil. Not much to see, everyone. Cheer up, carry on, these are not the droids you’re looking for.


In support of this insouciance, Shellenberger offers twelve “facts few people know”. Most of the points are defensible to some extent, and most of them raise interesting topics. A main purpose of this article is to provide references to the relevant discussions. But in going through it, it’s worth keeping an eye on the rhetorical purposes of the items, which appear a bit scattershot, and to the rhetorical purpose of the list, which might appear rather obscure.

Clearly labeling the list “facts that few people know” implies that all these points unambiguously refute common beliefs that are widely. And the “apology for the climate scare” indicates further that these beliefs are widely held by a supposedly misguided community of “climate scared”. A defender of the list, Blair King suggests that “[Shellenberger] identified false talking points used repeatedly by alarmists to misinform the public and move debate away from one that is evidence-based to one driven by fear and misinformation”. That does seem to be a fair reading of the stated intent of the list, but it just doesn’t ring true as a whole.

Speaking as a verteran “climate scared” person, the items don’t seem especially familiar. It’s hard to imagine a conversation like this:“Gosh, climate change is an even bigger threat to species than habitat loss.”“I know, and the land area used for producing meat is increasing!”As Gerardo Ceballos said:

This is not a scientific paper. It is intended, I guess, to be an article for the general public. Unfortunately, it is neither. It does not have a logical structure that allows the reader to understand what he would like to address, aside from a very general and misleading idea that environmentalists and climate scientists have been alarmist in relation to climate change. He lists a series of eclectic environmental problems like the Sixth Mass Extinction, green energy, and climate disruption. And without any data nor any proof, he discredits the idea that those are human-caused, severe environmental problems. He just mentions loose ideas about why he is right and the rest of the scientists, environmentalists, and general public are wrong.

What causes the strange incoherence of these “facts few people know”? At the end of this review I’ll propose an answer. Meanwhile, I will consider several questions regarding each item:

  • VALIDITY Is the claim unambiguously true? Unambiguously false? Disputed?
  • RELEVANCE TO CLIMATE Is the claim directly relevant to climate concern/”climate scare” or is it more of interest to tangentially related environmental issues?
  • SALIENCE Is the contrary of the claim widely believed by environmental activists? Does widespread belief in the claim contribute materially to an excess of climate concern?
  • IMPLICATION What is the rhetorical purpose of the question?
  • REALITY To what extent is the rhetorical purpose justified?
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Coronavirus and climate

Filed under: — gavin @ 20 March 2020

As we collectively reel from the changes wrought by the current pandemic, people are being drawn by analogy to climate issues – but analogies can be tricky and often distort as much as they illuminate.

For instance, in the Boston Globe, Jeff Jacoby’s commentary was not particularly insightful and misquoted Mike Mann pretty egregiously. Mike’s response is good:

I am relieved to see policy makers treating the coronavirus threat with the urgency it deserves. They need to do the same when it comes to an even greater underlying threat: human-caused climate change.

In a recent column (“I’m skeptical about climate alarmism, but I take coronavirus fears seriously,” Ideas, March 15), Jeff Jacoby sought to reconcile his longstanding rejection of the wisdom of scientific expertise when it comes to climate with his embrace of such expertise when it comes to the coronavirus.

In so doing, Jacoby took my words out of context, mischaracterizing my criticisms of those who overstate the climate threat “in a way that presents the problem as unsolvable, and feeds a sense of doom, inevitability, and hopelessness.”

As I have pointed out in past commentaries, the truth is bad enough when it comes to the devastating impacts of climate change, which include unprecedented floods, heat waves, drought, and wildfires that are now unfolding around the world, including the United States and Australia, where I am on sabbatical.

The evidence is clear that climate change is a serious challenge we must tackle now. There’s no need to exaggerate it, particularly when it feeds a paralyzing narrative of doom and hopelessness.

There is still time to avoid the worst outcomes, if we act boldly now, not out of fear, but out of confidence that the future is still largely in our hands. That sentiment hardly supports Jacoby’s narrative of climate change as an overblown problem or one that lacks urgency.

While we have only days to flatten the curve of the coronavirus, we’ve had years to flatten the curve of CO2 emissions. Unfortunately, thanks in part to people like Jacoby, we’re still currently on the climate pandemic path.

Michael E. Mann

State College, Pa.

The writer is a professor at Penn State University, where he is director of the Earth System Science Center.

Direct connections

There are some direct connections too. The lockdowns and travel restrictions are having a material effect on emissions of short-lived air pollutants (like NOx, SO2 etc.), water discharges and carbon dioxide as well. The impacts on air and water quality are already being seen – perhaps allowing people to reset their shifted baselines for what clean air and water are like.

Business-as-usual is kaput

Obviously, nothing is going to be quite the same after this. We will soon be describing prior norms and behaviours as “that is so BC” (before coronavirus). Already, when watching pre-recorded TV shows, I internally cringe when seeing the handshaking and hugging.

But it should also be obvious that for worst-case scenarios to materialise, it is a combination of factors that drive the results. Luck, good or bad, and decisions, wise or unwise, combine to create the future. Luck drives the specific potency of the virus, it’s incubation period and lethality, but societal decisions determined the preparation (or lack thereof), the health care system design or capacity (or lack thereof), and governmental responses (adequate or not).

Indeed, every possible future can only be reached by a specific track of what is (the science) and what we do about it (the policy). That is no different with climate as it is with pandemics. There is no possible future in which no-one made any decisions.

BAU wow wow

How should we discuss scenarios of future emissions? What is the range of scenarios we should explore? These are constant issues in climate modeling and policy discussions, and need to be reassessed every few years as knowledge improves.

I discussed some of this in a post on worst case scenarios a few months ago, but the issue has gained more prominence with a commentary by Zeke Hausfather and Glen Peters in Nature this week (which itself partially derives from ongoing twitter arguments which I won’t link to because there are only so many rabbit holes that you want to fall into).

My brief response to this is here though:

Mike Mann has a short discussion on this as well. But there are many different perspectives around – ranging from the merely posturing to the credible and constructive. The bigger questions are certainly worth discussing, but if the upshot of the current focus is that we just stop using the term ‘business-as-usual’ (as was suggested in the last IPCC report), then that is fine with me, but just not very substantive.


  1. Z. Hausfather, and G.P. Peters, "Emissions – the ‘business as usual’ story is misleading", Nature, vol. 577, pp. 618-620, 2020.

IPCC Special Report on Land

Thread for discussions of the new special report. [Boosting a comment from alan2102].

Climate Change and Land
An IPCC special report on climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems

Land degradation accelerates global climate change. Al Jazeera English
Published on Aug 8, 2019

New UN report highlights vicious cycle of climate change, land degradation. CNA
Published on Aug 8, 2019

New IPCC Report Warns of Vicious Cycle Between Soil Degradation and Climate Change. The Real News Network
Published on Aug 8, 2019

Absence and Evidence

Guest commentary by Michael Tobis, a retired climate scientist. He is a software developer and science writer living in Ottawa, Ontario.

A recent opinion piece by economist Ross McKitrick in the Financial Post, which attracted considerable attention in Canada, carried the provocative headline “This scientist proved climate change isn’t causing extreme weather – so politicians attacked”.

In fact, the scientist referenced in the headline, Roger Pielke Jr., proved no such thing. He examined some data, but he did not find compelling evidence regarding whether or not human influence is causing or influencing extreme events.

Should such a commonplace failure be broadly promoted as a decisive result that merits public interest?

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The best case for worst case scenarios

The “end of the world” or “good for you” are the two least likely among the spectrum of potential outcomes.

Stephen Schneider

Scientists have been looking at best, middling and worst case scenarios for anthropogenic climate change for decades. For instance, Stephen Schneider himself took a turn back in 2009. And others have postulated both far more rosy and far more catastrophic possibilities as well (with somewhat variable evidentiary bases).

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  1. S. Schneider, "The worst-case scenario", Nature, vol. 458, pp. 1104-1105, 2009.

4th National Climate Assessment report

Filed under: — gavin @ 23 November 2018

In possibly the biggest “Friday night news dump” in climate report history, the long awaited 4th National Climate Assessment (#NCA4) was released today (roughly two weeks earlier than everyone had been expecting).

The summaries and FAQ (pdf) are good, and the ClimateNexus briefing is worth reading too. The basic picture is utterly unsurprising, but the real interest in the NCA is the detailed work on vulnerabilities and sectorial impacts in 10 specific regions of the US. The writing teams for those sections include a whole raft of scientists and local stakeholders and so if you think climate reports are the same old, same old, it’s where you should go to read things you might not have seen before.

Obviously, since the report was only released at 2pm today without any serious embargo, most takes you will read today or tomorrow will be pretty superficial, but there should be more considered discussions over the next few days. Feel free to ask specific questions or bring up topics below.

Climate Change and Extreme Summer Weather Events – The Future is still in Our Hands

Summer 2018 saw an unprecedented spate of extreme weather events, from the floods in Japan, to the record heat waves across North America, Europe and Asia, to wildfires that threatened Greece and even parts of the Arctic. The heat and drought in the western U.S. culminated in the worst California wildfire on record. This is the face of climate change, I commented at the time.

Some of the connections with climate change here are pretty straightforward. One of the simplest relationships in all of atmospheric science tells us that the atmosphere holds exponentially more moisture as temperatures increase. Increased moisture means potentially for greater amounts of rainfall in short periods of time, i.e. worse floods. The same thermodynamic relationship, ironically, also explains why soils evaporate exponentially more moisture as ground temperatures increase, favoring more extreme drought in many regions. Summer heat waves increase in frequency and intensity with even modest (e.g. the observed roughly 2F) overall warming owing to the behavior of the positive “tail” of the bell curve when you shift the center of the curve even a small amount. Combine extreme heat and drought and you get more massive, faster-spreading wildfires. It’s not rocket science.

But there is more to the story. Because what made these events so devastating was not just the extreme nature of the meteorological episodes but their persistence. When a low-pressure center stalls and lingers over the same location for days at a time, you get record accumulation of rainfall and unprecedented flooding. That’s what happened with Hurricane Harvey last year and Hurricane Florence this year. It is also what happened with the floods in Japan earlier this summer and the record summer rainfall we experienced this summer here in Pennsylvania. Conversely, when a high-pressure center stalls over the same location, as happened in California, Europe, Asia and even up into the European Arctic this past summer, you get record heat, drought and wildfires.

Scientists such as Jennifer Francis have linked climate change to an increase in extreme weather events, especially during the winter season when the jet stream and “polar vortex” are relatively strong and energetic. The northern hemisphere jet stream owes its existence to the steep contrast in temperature in the middle latitudes (centered around 45N) between the warm equator and the cold Arctic. Since the Arctic is warming faster than the rest of the planet due to the melting of ice and other factors that amplify polar warming, that contrast is decreasing and the jet stream is getting slower. Just like a river traveling over gently sloping territory tends to exhibit wide meanders as it snakes its way toward the ocean, so too do the eastward-migrating wiggles in the jet stream (known as Rossby waves) tend to get larger in amplitude when the temperature contrast decreases. The larger the wiggles in the jet stream the more extreme the weather, with the peaks corresponding to high pressure at the surface and the troughs low pressure at the surface. The slower the jet stream, the longer these extremes in weather linger in the same locations, giving us more persistent weather extremes.

Something else happens in addition during summer, when the poleward temperature contrast is especially weak. The atmosphere can behave like a “wave guide”, trapping the shorter wavelength Rossby waves (those that that can fit 6 to 8 full wavelengths in a complete circuit around the Northern Hemisphere) to a relatively narrow range of latitudes centered in the mid-latitudes, preventing them from radiating energy away toward lower and higher latitudes. That allows the generally weak disturbances in this wavelength range to intensify through the physical process of resonance, yielding very large peaks and troughs at the sub-continental scale, i.e. unusually extreme regional weather anomalies. The phenomenon is known as Quasi-Resonant Amplification or “QRA”, and (see Figure below).

Many of the most damaging extreme summer weather events in recent decades have been associated with QRA, including the 2003 European heatwave, the 2010 Russian heatwave and wildfires and Pakistan floods (see below), and the 2011 Texas/Oklahoma droughts. More recent examples include the 2013 European floods, the 2015 California wildfires, the 2016 Alberta wildfires and, indeed, the unprecedented array of extreme summer weather events we witnessed this past summer.

The increase in the frequency of these events over time is seen to coincide with an index of Arctic amplification (the difference between warming in the Arctic and the rest of the Northern Hemisphere), suggestive of a connection (see Figure below).

Last year we (me and a team of collaborators including RealClimate colleague Stefan Rahmstorf) published an article in the Nature journal Scientific Reports demonstrating that the same pattern of amplified Arctic warming (“Arctic Amplification”) that is slowing down the jet stream is indeed also increasing the frequency of QRA episodes. That means regional weather extremes that persist longer during summer when the jet stream is already at its weakest. Based on an analysis of climate observations and historical climate simulations, we concluded that the “signal” of human influence on QRA has likely emerged from the “noise” of natural variability over the past decade and a half. In summer 2018, I would argue, that signal was no longer subtle. It played out in real time on our television screens and newspaper headlines in the form of an unprecedented hemisphere-wide pattern of extreme floods, droughts, heat waves and wildfires.

In a follow-up article just published in the AAAS journal Science Advances, we look at future projections of QRA using state-of-the-art climate model simulations. It is important to note that that one cannot directly analyze QRA behavior in a climate model simulation for technical reasons. Most climate models are run at grid resolutions of a degree in latitude or more. The physics that characterizes QRA behavior of Rossby Waves faces a stiff challenge when it comes to climate models because it involves the second mathematical derivative of the jet stream wind with respect to latitude. Errors increase dramatically when you calculate a numerical first derivative from gridded fields and even more so when you calculate a second derivative. Our calculations show that the critical term mentioned above suffers from an average climate model error of more than 300% relative to observations. By contrast, the average error of the models is less than a percent when it comes to latitudinal temperature averages and still only about 30% when it comes to the latitudinal derivative of temperature.

That last quantity is especially relevant because QRA events have been shown to have a well-defined signature in terms of the latitudinal variation in temperature in the lower atmosphere. Through a well-established meteorological relationship known as the thermal wind, the magnitude of the jet stream winds is in fact largely determined by the average of that quantity over the lower atmosphere. And as we have seen above, this quantity is well captured by the models (in large part because the change in temperature with latitude and how it responds to increasing greenhouse gas concentrations depends on physics that are well understood and well represented by the climate models).

These findings, incidentally have broader implications. First of all, climate model-based studies used to assess the degree to which current extreme weather events can be attributed to climate change are likely underestimating the climate change influence. One model-based study for example suggested that climate change only doubled the likelihood of the extreme European heat wave this summer. As I commented at the time, that estimate is likely too low for it doesn’t account for the role that we happen to know, in this case, that QRA played in that event. Similarly, climate models used to project future changes in extreme weather behavior likely underestimate the impact that future climate changes could have on the incidence of persistent summer weather extremes like those we witnessed this past summer.

So what does our study have to say about the future? We find that the incidence of QRA events would likely continue to increase at the same rate it has in recent decades if we continue to simply add carbon dioxide to the atmosphere. But there’s a catch: The future emissions scenarios used in making future climate projections must also account for factors other than greenhouse gases. Historically, for example, the use of old coal technology that predates the clean air acts produced sulphur dioxide gas which escapes into the atmosphere where it reacts with other atmospheric constituents to form what are known as aerosols.

These aerosols caused acid rain and other environmental problems in the U.S. before factories in the 1970s were required to install “scrubbers” to remove the sulphur dioxide before it leaves factory smokestacks. These aerosols also reflect incoming sunlight and so have a cooling effect on the surface in the industrial middle-latitudes where they are produced. Some countries, like China, are still engaged in the older, dirtier-form of coal burning. If we continue with business-as-usual burning of fossil fuels, but countries like China transition to more modern “cleaner” coal burning to avoid air pollution problems, we are likely to see a substantial drop in aerosols over the next half century. Such an assumption is made in the Intergovernmental Panel on Climate Change (IPCC)’s “RCP 8.5” scenario—basically, a “business as usual” future emissions scenario which results in more than a tripling of carbon dioxide concentrations relative to pre-industrial levels (280 parts per million) and roughly 4-5C (7-9F) of planetary warming by the end of the century.

As a result, the projected disappearance of cooling aerosols in the decades ahead produces an especially large amount of warming in middle-latitudes in summer (when there is the most incoming sunlight to begin with, and, thus, the most sunlight to reflect back to space). Averaged across the various IPCC climate models there is even more warming in mid-latitudes than in the Arctic—in other words, the opposite of Arctic Amplification i.e. Arctic De-amplification (see Figure below). Later in the century after the aerosols disappear greenhouse warming once again dominates and we again see an increase in QRA events.

So, is there any hope to avoid future summers like the summer of 2018? Probably not. But in the scenario where we rapidly move away from fossil fuels and stabilize greenhouse gas concentrations below 450 parts per million, giving us a roughly 50% chance of averting 2C/3.6F planetary warming (the so-called “RCP 2.6” IPCC scenario) we find that the frequency of QRA events remains roughly constant at current levels.

While we will presumably have to contend with many more summers like 2018 in the future, we could likely prevent any further increase in persistent summer weather extremes. In other words, the future is still very much in our hands when it comes to dangerous and damaging summer weather extremes. It’s simply a matter of our willpower to transition quickly from fossil fuels to renewable energy.

European climate services take an important leap forward 

An important milestone was passed during the second general assembly of the Copernicus Climate Change Service, which took place in Berlin on Sept 24-28 (twitter hashtag '#C3SGA18'). The European climate service has become operational, hosted by the European Centre for Medium-Range Forecasts (ECMWF).

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Musing about Losing Earth

The NY Times Magazine has a special issue this weekend on climate change. The main article is “Losing the Earth” by Nathaniel Rich, is premised on the idea that in the period 1979 to 1989 when we basically knew everything we needed to know that climate change was a risk, and the politics had not yet been polarized, we missed our opportunity to act. Stated this way, it would probably be uncontroversial, but since the article puts the blame for this on “human nature”, rather than any actual humans, extensive Twitter discussion ensues…

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