Climate scientists have two main tasks with respect to the climate crisis: to conduct detailed research on the mounting problems and to provide reliable guidance regarding their solutions. They have admirably performed the first task. Their painstaking investigations have revealed that climate change is real, human-caused, and extremely serious. They have given us a detailed understanding of the climate system’s chemistry and physics, and they have developed sophisticated computer models to project future climate trends as the Earth warms.
Unfortunately the scientists have not done nearly as well on the solutions side. As I explain below, their contributions here are counterfactual and illogical, leaving humankind without reliable guidance just when this is most urgently required.
The disparity between these two sides of climate science – problems research and solutions analysis – is so pronounced that an explanation must be offered before I proceed. Two factors appear to be critical. The first is the intense political pressure to avoid disrupting economic growth. The current economic system is inherently expansionary, but any serious attempt to address climate change will entail significant contraction. Powerful forces fiercely resist this fundamental shift. The second factor is an expression of the first: climate denialism. Although many climate scientists have bravely resisted denier attacks, most have likely succumbed to some form of self-censorship, in both private thoughts and public statements.
The remainder of this article identifies six key distortions that climate scientists have been persuaded or compelled to embrace. To illustrate my points I will use the first volume of the fourth US National Climate Assessment (NCA4), which was released in November, 2017. I will also refer to a New York Times article by four of the report’s lead authors. Because I am an independent thinker rather than a climate scientist, I have consulted with several members of the climate community to ensure that my assertions are scientifically sound. Note also that, although I use the IPCC’s technical definitions, I believe this organization is deeply compromised. This topic will be addressed in future posts.
Before getting to the specifics, let me point to the core issue. This is the absence of a rigorous conceptual framework for interpreting research results and formulating a rational crisis response. NCA4, for example, provides detailed information about the coming droughts, floods, storms, rising seas, and acidifying oceans. However, the chapter on mitigation provides no clear insight about the causal relationships between greenhouse gases (GHGs) and these phenomena, and it fails to scientifically establish the report’s conclusion that emissions reduction is the correct solution. After reading the report we know what is wrong, but not how to think about what is wrong – or how to fix it. What follows is intended to clarify and substantiate this claim.
1. The rational GHG goal is not zero emissions, but zero unsafe concentrations.
The international treaty that underpins the IPCC-based process to address climate change is the UNFCCC – the United Nations Framework Convention on Climate Change. Ratified in 1994, its stated objective is, “… stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system.” This goal accurately reflects physical reality: climate change is caused by GHG concentrations that have exceeded their safe levels. Although the IPCC has a different view, the determination of these levels is a scientific issue, and must therefore be based on the best available scientific evidence.
Thus, if such evidence indicates that 350 ppm is the maximum safe level for CO2, and if the current level is 405 ppm, then this part of the core problem is 55 ppm of excess CO2. The annual increments of 2-3 ppm exacerbate the problem, but they do not constitute it. This inescapably implies that the rational aim for GHGs is not reduced or zero emissions, but zero unsafe concentrations. Emissions must decline, but as part of the concentrations declines, not as the end itself.
The field’s standard retort is that technologies exist for reducing emissions, but not for reducing concentrations. This issue, however, is beyond the purview of climate scientists. Their job is to present effective solutions to society. It is society’s job to respond by developing the required technologies. If climate scientists had honored the UNFCCC goal by repeatedly insisting on the urgent need for GHG-removal technologies, these might have been developed. They have not done so, and predictably the technologies remain largely absent.
2. “Global warming” and “climate change” are often conflated, and “climate change” is frequently misused.
The conflation is not just a semantic quibble. Global warming is conceptually distinct from climate change, and merging the two destroys coherent thought. According to the IPCC’s definitions, global warming is the increase in global surface temperature as a result of radiative forcing caused by GHGs. Climate change, on the other hand, refers to a persistent change in the state of the climate. The causal sequence is therefore: excess GHGs … radiative forcing … global warming … climate change. Global warming is a cause; climate change is one of its effects. From the scientific perspective it is unacceptable to merge them into a single phenomenon.
Once these critical terms are clearly distinguished the correct picture quickly comes into view:
As shown at left, the root of all GHG evil is unsafe concentrations. These have both warming and chemical effects: global warming from all GHGs and ocean acidification from CO2 alone. Global warming heats the global ocean, which in turn causes ocean deoxygenation. After a delay of several decades due to its thermal inertia, the ocean releases its excess heat to the atmosphere and causes climate change. Global warming also has a small immediate effect on climate change, as shown at the top of the diagram. (The 93/7 split is from NCA4.)
Back to the terms: the only excuse for conflating “global warming” and “climate change” is that they can be used interchangeably in battling the deniers. But this is irrelevant. Anti-denialism is a different project from the scientific characterization of the GHG-based disasters. Climate scientists can say what they like to the non-believers, but they have a responsibility to be precise and rigorous when describing these existential dangers to society as a whole.
There is an even more basic issue here: the absence of a dedicated term for the full set of environmental problems resulting from unsafe GHG levels. Think about it: if you had to refer to the harmful GHG effects collectively, what term would you use? That is, what would you call the overall problem that is addressed in the above diagram? Because there is a vacuum here, “climate change” (or its spin-off, “climate crisis”) has been appropriated for this purpose. This is why NCA4, which is introduced as, “… an authoritative assessment of the science of climate change …” (p. 1) covers the topic of ocean acidification, which is a purely chemical effect having nothing to do with either global warming or climate change if these are properly defined.
This means that “climate change” is now used in two very different ways: scientifically as a reference to a persistent change in the climate, and in arm-waving fashion as a reference to the full GHG problem set. I can’t be alone in thinking that this is a ludicrous and irresponsible situation.
(At this point I should note that my introduction to this post used standard terminology that must be adjusted based on the clarifications just presented.)
3. The danger from global warming is not the temperature increase itself, but the ecological damage that results.
According to the authors of the New York Times article, the global temperature increase must be stabilized below 2°C to avoid, “… potentially unforeseen and even catastrophic changes to the climate”. I’ll come back to the two degrees shortly, but here I want to make an underlying point: humankind and nature are threatened not by higher climatic temperatures per se, but by ecological damage. Higher temperatures are an important factor in ecological damage, but they do not constitute the problem itself.
The question here relates to the implicit mathematical function used by climate science to determine the damage done by global warming to the environment. In most of the field’s statements, damage is a function of rising temperature alone. Occasionally, the speed of this rise is also considered. What is rarely included is the duration of the heightened temperature. But surely a temperature rise of two degrees for a year would be far less damaging than a rise of one degree for a century. Time matters, and for the environment it matters a lot.
The conclusion is this: the danger we face from global warming is its ecological damage, which is determined by the speed, magnitude, and duration of the elevated temperature. Climate science would be greatly improved if it adopted this as its explicit damage function rather than continuing with the implicit and faulty version it currently employs.
4. The two-degree limit has no scientific basis and is far too high.
The distortions discussed above involve logical lapses that could be ascribed to the political pressures facing climate scientists. The presumed safe limit of 2°C is in a different category. To use a trite but apt metaphor, this is a case of the emperor wearing no clothes.
The main objection is that there is no scientific basis whatsoever for this “safe” limit to the rising global temperature. This is clearly demonstrated by NCA4, which on p. 397 tries to justify its use. We are first told that the two-degree limit appeared in the scientific literature as early as 1975, but there is no indication that this number was scientifically grounded. We are then informed that, in the same year, economist William Nordhaus speculated that an increase of two or three degrees would take the atmosphere outside its normal range. Although these are relatively insignificant developments, the 2°C limit has now been universally adopted.
So the bald truth is that a brazenly concocted number has become the basis for international negotiations, scientific studies and reports, and the “carbon budget” – the amount of carbon we can purportedly emit while remaining within the two-degree limit. If this is not the madness of a naked king, what is it?
Unfortunately that’s not all: the chosen number is far too high. This is obvious given the visible damage already caused by the current temperature increase of just over 1°C, but there is strong scientific evidence as well. As reported here, Oxford geoscientist Anton Vaks has found that, about 400,000 years ago, Siberian permafrost began to melt when the global temperature was 1.5 ºC above the pre-industrial level. Peter Wadhams, a veteran Arctic researcher at Cambridge University, states in A Farewell to Ice that the Arctic’s shallow seas hit a tipping point in 2005 when their summer ice covers disappeared, thereby exposing methane hydrates in the seabeds to warmer waters. The threat in both cases is the release of enormous quantities of carbon, with results that could easily overwhelm our species. A further rise to two degrees would clearly be catastrophic.
To complete this sad tale, let me place the 2°C limit in the context of the ecological damage function discussed above:
Recall that the three factors are speed, magnitude, and duration. According to a Stanford study, the speed of today’s warming is ten times faster than any warming event in the past 65 million years. The magnitude of two degrees, as stated, is too high. And so long as the focus is on emissions instead of unsafe concentrations, the heightened temperature will persist indefinitely. The combined effect of these three factors is a roaring crescendo of ecological damage that is certain to pass tipping points and points-of-no-return in the near future. In other words, the grand hope that climate science is now presenting to the world leads inevitably to ecological disaster.
5. The common term “mitigation” is ambiguous and frequently misused.
I must return to terminology because this is how the distortions are disseminated on a daily basis. This is especially true for “mitigation”.
According to all official glossaries that include the term, “mitigation” refers to both the reduction of GHG sources (emissions) and the enhancement of GHG sinks (removals). Nevertheless, in practice, it is frequently used in reference to sources alone. Further, sink enhancement sometimes refers to CO2 exclusively and at other times to all GHGs. There are thus several conflicting definitions floating around. This means that the mantra of “mitigate and adapt” is highly ambiguous: unless clarification is offered, no-one knows what it really means.
The muddle is even worse than this. The IPCC glossary lists the term as, “Mitigation (of climate change),” indicating that it should be applied to the problem rather than the GHGs that cause the problem. Despite this, NCA4 (and the IPCC itself!) talks not only about mitigating climate change but also about mitigating emissions. (p. 16) The latter usage is suspect because it is unnecessary. Emissions can be reduced, decreased, lowered, lessened, diminished, brought down, or minimized. When the English language provides so many options, why use “mitigate” in this context when confusion will be the inevitable result?
To bottom-line this mess: “mitigation” correctly refers to reduced sources and enhanced sinks for all GHGs in order to reduce the severity of the GHG-based emergencies (not just climate change). Any other interpretation is a departure from the precision and rigor that climate scientists have a responsibility to uphold.
One last point: Since all official definitions of “mitigation” include carbon dioxide removal (CDR), there is an overlap with the standard definition of “geoengineering” (CDR plus solar radiation management). Those who support mitigation but oppose geoengineering therefore hold a position that is rooted in terminological error. This brings me to …
6. Geoengineering, which is the ONLY solution to global warming, has been deceptively marginalized.
The most dangerous of the six distortions has been saved for last. This is the field’s treatment of geoengineering, which has been mocked and marginalized despite its existential significance. (For a striking example of this dismissive posture, see Chapter 7 in Michael Mann’s The Madhouse Effect.) What is especially distressing is that the core scientific facts about geoengineering have been consistently suppressed. Let me quickly fill this shameful gap.
Prior to the era of global warming the energy flowing from the Sun to the Earth was balanced by the heat radiating from the Earth into space. The global temperature was therefore stable. Excess GHGs upset this balance by decreasing the heat outflow, thereby raising the global temperature. Geoengineering is the reversal of this destructive process. It restores the heat balance by decreasing heat inflow (solar radiation management or SRM) and increasing heat outflow (carbon dioxide removal or CDR). Geoengineering is thus the thermodynamic opposite of global warming, and as such it is the fix – the ONLY fix – for this catastrophe. Zero emissions would eventually stop the warming process, but by the laws of physics they can’t reverse it. For more on this topic, see here and here.
NCA4 addresses geoengineering in the standard, superficial manner. For the SRM component it first warns readers about the imminent dangers that can be tackled only by this approach (pp. 314 and 315). It then reassures us that these dangers probably won’t be realized (p. 315), and it finally dismisses SRM by citing its risks and calling for further research (p. 403). Given the extraordinary threats we face from the rapidly melting Arctic and SRM’s unique potential for averting them, this is a feeble and evasive analysis.
NCA4’s take on CDR is similarly deficient. First and most obviously, this should be called “GHG removals” or similar to include all GHGs, not just CO2. The report fails to point this out. Second, GHG removals are characterized as “negative emissions” – a measure to be employed only after emissions have been reduced to zero. The deceptive image is therefore that of a thermometer, where a positive temperature must go through zero to reach negative territory. An honest image would be that of a filling bathtub, which can be emptied by simultaneously closing the tap (emissions reductions) and pulling the plug (GHG removals). Also, as noted below, the “negative emissions” idea postpones GHG removals by several decades and thus permits ecological damage that could have been avoided.
In brief, climate science in its current state is depriving humankind of reliable information, accurate images, and sound advice regarding geoengineering – a set of methods that, with due regard for the risks involved, must be employed quickly and decisively to maintain a livable environment.
All of this is maddening because the solution to the GHG-based emergencies is, at least in principle, stunningly simple: GHG concentrations must be returned to their safe levels, and this must be done as quickly as technically and socially feasible. These imperatives are depicted in the graph below, which tracks the level of unsafe GHG concentrations over time.
This graph quantifies the ecological damage to which humankind must adapt before the GHG peril has been negated. The area under the curve to the left of the dotted line – the present time – represents the damage to which we are inexorably committed. The area to the right represents unavoidable future damage, which is determined by the fastest feasible rate of concentrations declines.
Note that the total damage, while extensive, is limited: the curve is closed. By contrast, the damage from the two-degree approach is unlimited: the curve is open. It goes without saying that only limited damage can prevent ecological collapse, and the less the better. Given these realities, it is truly alarming that the NCA4 authors would delay even the possibility of GHG removals until “later in the century”. (p. 31) This is disturbingly unethical because it would avoidably increase future damage, thereby causing unnecessary suffering and deaths from the associated environmental disasters.
A notable feature of the above graph is the absence of temperature. This is because temperature is irrelevant to a rational GHG strategy. If this sounds wrong, consider an analogy.
If your roof is creaking because the snow is piling up, you wouldn’t estimate that two hours remain before it collapses and then watch television for another hour before taking action. No, you’d get up there immediately and start shoveling as fast as you can. Why? Because you have no idea if your estimate is correct: collapse could come in five or thirty minutes. But excess GHGs have been causing loud creaks in the global environment for decades. The only reasonable response is to shovel those concentrations away as quickly as possible, regardless of any “safe” temperature projections.
To conclude, the indicated solution will entail extremely rapid emissions reductions and likely an investment of several trillion dollars in GHG-removal methods and technologies. On the social front it will mean fundamental political and economic transformations. Succinctly stated, a GHG-based cataclysm can be prevented only if the social world is profoundly changed, and if the solutions side of climate science is urgently rectified.
January 16, 2018
Updates and edits: Dec. 18/18