climate geoengineering

On the NASEM report on solar geoengineering

A top scientific body in the US has asked the government to fund solar geoengineering research in a bid to help researchers and policymakers know the fullest extent of their options to help the US deal with climate change.

Solar geoengineering is a technique in which sunlight-reflecting aerosols are pumped into the air, to subtract the contribution of solar energy to Earth’s rapidly warming surface.

The technique is controversial because the resulting solar dimming is likely to affect ecosystems in a detrimental way and because, without the right policy safeguards, its use could allow polluting industries to continue polluting.

The US National Academies of Sciences, Engineering and Medicine (NASEM) released its report on March 25. It describes three solar geoengineering strategies: stratospheric aerosol injection (described above), marine cloud brightening and cirrus cloud thinning.

“Although scientific agencies in the US and abroad have funded solar-geoengineering research in the past, governments have shied away from launching formal programmes in the controversial field,” Nature News reported. In addition, “Previous recommendations on the subject by elite scientific panels in the US and abroad have gone largely unheeded” – including NASEM’s own 2015 recommendations.

To offset potential roadblocks, the new report requests the US government to setup a transparent research administration framework, including a code of conduct, an open registry of researchers’ proposals for studies and a fixed process by which the government will grant permits for “outdoor experiments”. And to achieve these goals, it recommends a dedicated allocation of $100-200 million (Rs 728-1,456 crore).

According to experts who spoke to Nature News, Joe Biden being in the Oval Office instead of Donald Trump is crucial: “many scientists say that Biden’s administration has the credibility to advance geoengineering research without rousing fears that doing so will merely displace regulations and other efforts to curb greenhouse gases, and give industry a free pass.”

This is a significant concern for many reasons – including, notably, countries’ differentiated commitments to ensuring outcomes specified in the Paris Agreement and the fact that climate is a global, not local, phenomenon.

Data from 1900 to 2017 indicates that US residents had the world’s ninth highest carbon dioxide emissions per capita; Indians were 116th. This disparity, which holds between the group of large developed countries and of large developing countries in general, has given rise to demands by the latter that the former should do more to tackle climate change.

The global nature of climate is a problem particularly for countries with industries that depend on natural resources like solar energy and seasonal rainfall. One potential outcome of geoengineering is that climatic changes induced in one part of the planet could affect outcomes in a faraway part.

For example, the US government sowed the first major seeds of its climate research programme in the late 1950s after the erstwhile Soviet Union set off three nuclear explosions underground to divert the flow of a river. American officials were alarmed because they were concerned that changes to the quality and temperature of water entering the Arctic Ocean could affect climate patterns.

For another, a study published in 2007 found that when Mt Pinatubo in the Philippines erupted in 1991, it spewed 20 million tonnes of sulphur dioxide that cooled the whole planet by 0.5º C. As a result, the amount of rainfall dropped around the world as well.

In a 2018 article, Rob Bellamy, a Presidential Fellow in Environment at the University of Manchester, had also explained why stratospheric aerosol injection is “a particularly divisive idea”:

For example, as well as threatening to disrupt regional weather patterns, it, and the related idea of brightening clouds at sea, would require regular “top-ups” to maintain cooling effects. Because of this, both methods would suffer from the risk of a “termination effect”: where any cessation of cooling would result in a sudden rise in global temperature in line with the level of greenhouse gases in the atmosphere. If we hadn’t been reducing our greenhouse gas emissions in the background, this could be a very sharp rise indeed.

A study published in 2018 had sought to quantify the extent of this effect – a likely outcome of, say, projects losing political favour or funding. The researchers created a model in which humans pumped five million tonnes of sulphur dioxide a year into the stratosphere for 50 years, and suddenly stopped. One of the paper’s authors told The Wire Science at the time: “This would lead to a rapid increase in temperature, two- to four-times more rapid than climate change without geoengineering. This increase would be dangerous for biodiversity and ecosystems.”

Prakash Kashwan, a political scientist at the University of Connecticut and a senior research fellow of the Earth System Governance Project, has also written for The Wire Science about the oft-ignored political and social dimensions of geoengineering.

He told the New York Times on March 25, “Once these kinds of projects get into the political process, the scientists who are adding all of these qualifiers and all of these cautionary notes” – such as “the steps urged in the report to protect the interests of poorer countries” – “aren’t in control”. In December 2018, Kashwan also advised caution in the face of scientific pronouncements:

The community of climate engineering scientists tends to frame geoengineering in certain ways over other equally valid alternatives. This includes considering the global average surface temperature as the central climate impact indicator and ignoring vested interests linked to capital-intensive geoengineering infrastructure. This could bias future R&D trajectories in this area. And these priorities, together with the assessments produced by eminent scientific bodies, have contributed to the rise of a de facto form of governance. In other words, some ‘high-level’ scientific pronouncements have assumed stewardship of climate geoengineering in the absence of other agents. Such technocratic modes of governance don’t enjoy broad-based social or political legitimacy.

For now, the NASEM report “does not in any way advocate deploying the technology, but says research is needed to understand the options if the climate crisis becomes even more serious,” according to Nature News. The report itself concludes thus:

The recommendations in this report focus on an initial, exploratory phase of a research program. The program might be continued or expand over a longer term, but may also shrink over time, with some or all elements eventually terminated, if early research suggests strong reasons why solar geoengineering should not be pursued. The proposed approaches to transdisciplinary research, research governance, and robust stakeholder engagement are different from typical climate research programs and will be a significant undertaking; but such efforts will enable the research to proceed in an effective, societally responsive manner.

Matthew Watson, a reader in natural hazards at the University of Bristol, had discussed a similar issue in conversation with Bellamy in 2018, including an appeal to our moral responsibilities the same way ‘geoengineers’ must be expected to look out for transnational and subnational effects:

Do you remember the film 127 Hours? It tells the (true) story of a young climber who, pinned under a boulder in the middle of nowhere, eventually ends up amputating his arm, without anaesthetic, with a pen knife. In the end, he had little choice. Circumstances dictate decisions. So if you believe climate change is going to be severe, you have no option but to research the options (I am not advocating deployment) as broadly as possible. Because there may well come a point in the future where it would be immoral not to intervene.

The Wire Science
March 30, 2021

The difficulty of option ‘c’

Can any journalist become a science journalist? More specifically, can any journalist become a science journalist without understanding the methods of scientific practice and administration? This is not a trivial question because not all the methods of science can be discovered or discerned from the corresponding ‘first principles’. That is, common sense and intelligence alone cannot consummate your transformation; you must access new information that you cannot derive through inductive reasoning.

For example, how would you treat the following statement: “Scientists prove that X causes Y”?

a. You could take the statement at face-value

b. You could probe how and why scientists proved that X causes Y

c. You could interrogate the claim that X causes Y, or

d. You could, of course, ignore it.

(Option (d) is the way to go for claims in the popular as well as scientific literature of the type “Scientists prove that coffee/wine/chocolate cause your heart to strengthen/weaken/etc.” unless the story you’re working on concerns the meta-narrative of these studies.)

Any way, choosing between (a), (b) and (c) is not easy, often because which option you pick depends on how much you know about how the modern scientific industry works. For example, a non-science journalist is likely to go with (a) and/or (b) because, first, they typically believe that the act of proving something is a singular event, localised in time and space, with no room for disagreement.

This is after all the picture of proof-making that ill-informed supporters of science (arguably more than even supporters of the ideal of scientism) harbour: “Scientists have proved that X causes Y, so that’s that,” in the service of silencing inconvenient claims like “human activities aren’t causing Earth’s surface to heat up” or like “climate geoengineering is bad”. I believe that anthropogenic global warming is real and that we need to consider stratospheric aerosol injections but flattening the proof-making exercise threatens to marginalise disagreements among scientists themselves, such as about the extent of warming or about the long-term effects on biodiversity.

The second reason (a) and (b) type stories are more common, but especially (a), follows from this perspective of proofs: the view that scientists are authorities, and we are not qualified to question them. As it happens, most of us will never be qualified enough, but question them we can thanks to four axioms.

First, science being deployed for the public good must be well understood in much the same way a drug that has been tested for efficacy must also be exculpated of deleterious side-effects.

Second, journalists don’t need to critique the choice of reagents, animal models, numerical methods or apparatus design to be able to uncover loopholes, inconsistencies and/or shortcomings. Instead, that oppositional role is easily performed by independent scientists whose comments a journalist can invite on the study.

Third, science is nothing without the humans that practice it, and most of the more accessible stories of science (not news reports) are really stories of the humans practising the science.

Fourth, organised science – hot take: like organised religion – is a human endeavour tied up with human structures, human politics and human foibles, which means as much of what we identify as science lies in the discovery of scientific knowledge as in the way we fund, organise, disseminate and preserve that knowledge.

These four allowances together imply that a science journalist is not a journalist familiar with advanced mathematics or who can perform a tricky experiment but is a journalist trained to write about science without requiring such knowledge.

Anyone familiar with India will recognise that these two principal barriers – a limited understanding of proof-making and the view of scientists as authority figures – to becoming a good science journalist are practically seeded by the inadequate school-level education system. But they are also furthered by India’s prevailing political climate, especially in the way a highly polarised society undermines the role of expertise.

Some people will tell you that you can’t question highly trained scientists because you are not a highly trained scientist but others will say you’re entitled to question everything as a thinking, reasoning, socially engaged global citizen.

As it happens, these aren’t opposing points of view. It’s just that the left and the right have broken the idea of expertise into two pieces, taking one each for themselves, such that the political left is often comfortable with questioning facts like grinding bricks to unusable dust while the political right will treat all bricks the same irrespective of the quality of clay; the leftist will subsequently insist that quality control is all-important whereas the rightist will champion the virtues of pragmatism.

In this fracas to deprive expertise either of authority or of critique, or sometimes both, the expert becomes deconstructed to the point of nonexistence. As a result, the effective performance of science journalism, instead of trying to pander equally to the left’s and the right’s respective conceptions of the expert, converges on the attempt to reconstruct expertise as it should be: interrogated without undermining it, considered without elevating it.

Obviously, this is easier said, and more enjoyably said, than done.

Prestige journals and their prestigious mistakes

On June 24, the journal Nature Scientific Reports published a paper claiming that Earth’s surface was warming by more than what non-anthropogenic sources could account for because it was simply moving closer to the Sun. I.e. global warming was the result of changes in the Earth-Sun distance. Excerpt:

The oscillations of the baseline of solar magnetic field are likely to be caused by the solar inertial motion about the barycentre of the solar system caused by large planets. This, in turn, is closely linked to an increase of solar irradiance caused by the positions of the Sun either closer to aphelion and autumn equinox or perihelion and spring equinox. Therefore, the oscillations of the baseline define the global trend of solar magnetic field and solar irradiance over a period of about 2100 years. In the current millennium since Maunder minimum we have the increase of the baseline magnetic field and solar irradiance for another 580 years. This increase leads to the terrestrial temperature increase as noted by Akasofu [26] during the past two hundred years.

The New Scientist reported on July 16 that Nature has since kickstarted an “established process” to investigate how a paper with “egregious errors” cleared peer-review and was published. One of the scientists it quotes says the journal should retract the paper if it wants to “retain any credibility”, but the fact that it cleared peer-review in the first place is to me the most notable part of this story. It is a reminder that peer-review has a failure rate as well as that ‘prestige’ titles like Nature can publish crap; for instance, look at the retraction index chart here).

That said, I am a little concerned because Scientific Reports is an open-access title. I hope it didn’t simply publish the paper in exchange for a fee like its less credible counterparts.

Almost as if it timed it to the day, the journal Science – Nature‘s big rival across the ocean – published a paper that did make legitimate claims but which brooks disagreement on a different tack. It describes a way to keep sea levels from rising due to the melting of Antarctic ice. Excerpt:

… we show that the [West Antarctic Ice Sheet] may be stabilized through mass deposition in coastal regions around Pine Island and Thwaites glaciers. In our numerical simulations, a minimum of 7400 [billion tonnes] of additional snowfall stabilizes the flow if applied over a short period of 10 years onto the region (~2 mm/year sea level equivalent). Mass deposition at a lower rate increases the intervention time and the required total amount of snow.

While I’m all for curiosity-driven research, climate change is rapidly becoming a climate emergency in many parts of the world, not least where the poorer live, without a corresponding set of protocols, resources and schemes to deal with it. In this situation, papers like this – and journals like Science that publish them – only make solutions like the one proposed above seem credible when in fact they should be trashed for implying that it’s okay to keep emitting more carbon into the atmosphere because we can apply a band-aid of snow over the ice sheet and postpone the consequences. Of course, the paper’s authors acknowledge the following:

Operations such as the one discussed pose the risk of moral hazard. We therefore stress that these projects are not an alternative to strengthening the efforts of climate mitigation. The ambitious reduction of greenhouse gas emissions is and will be the main lever to mitigate the impacts of sea level rise. The simulations of the current study do not consider a warming ocean and atmosphere as can be expected from the increase in anthropogenic CO2. The computed mass deposition scenarios are therefore valid only under a simultaneous drastic reduction of global CO2 emissions.

… but these words belong in the last few lines of the paper (before the ‘materials and methods’ section), as if they were a token addition to what reads, overall, like a dispassionate analysis. This is also borne out by the study not having modelled the deposition idea together with falling CO2 emissions.

I’m a big fan of curiosity-driven science as a matter of principle. While it seemed hard at first to reconcile my emotions on the Science paper with that position, I realised that I believe both curiosity- and application-driven research should still be conscientious. Setting aside the endless questions about how we ought to spend the taxpayers’ dollars – if only because interfering with research on the basis of public interest is a terrible idea – it is my personal, non-prescriptive opinion that research should still endeavour to be non-destructive (at least to the best of the researchers’ knowledge) when advancing new solutions to known problems.

If that is not possible, then researchers should acknowledge that their work could have real consequences and, setting aside all pretence of being quantitative, objective, etc., clarify the moral qualities of their work. This the authors of the Science paper have done but there are no brownie points for low-hanging fruits. Or maybe there should be considering there has been other work where the authors of a paper have written that they “make no judgment on the desirability” of their proposal (also about climate geo-engineering).

Most of all, let us not forget that being Nature or Science doesn’t automatically make what they put out better for having been published by them.