On the other hand, a programme might be triggered by a specific event — for example, something sudden and dire happening in the Arctic. Some such events (lots of methane coming out of permafrost) might indeed be checked by prompt cooling, though you might need rather a lot of it. Other catastrophes (radical destabilisation of Greenland ice) probably wouldn’t be helped at all. But such an emergency might trigger demands for prompt climate action that politicians found hard to ignore, and climate geoengineering might be the prompt action they turned to whether or not it met the needs of the specific emergency.

I’ve always seen this as a rather worrying scenario. Much better to think carefully about climate geoengineering’s merits and dangers and build it into a portfolio of climate action than to be bounced into it as some sort of new alternative. Among other drawbacks, a programme put together in the context of a climate emergency might have to be sized so as to deliver a dramatic effect — one with a cooling that might be measured in watts per square metre, rather than something a tenth that size — right away. This seems likely to be imprudent.

A new paper by Jim Haywood and colleagues at the Met Office and the University of Exeter in Nature Climate Change brings up a new version of this question, though, one which I find intriguing. What about the use of geoengineering to counteract a natural, rather than man-made, climatic event? (Disclosure: after hearing Jim talk about this work at a meeting last year I discussed it with him quite a lot, to the extent of eventually being acknowledged in the paper. That’s why I’m writing about it in a personal capacity here, rather than in print somewhere. Obviously the opinions in this post are purely my own.)

The research started out looking at what might happen if a climate geoengineering programme put sulphate aerosols into the stratosphere of either just the northern hemisphere, or just the southern hemisphere. The first order answer is that the hemisphere with the hazy stratosphere ends up cooled and the other doesn’t, which is kind of obvious. What is not so obvious is what happens to the Sahel, the band of countries arrayed along and below the southern edge of the Sahara. If you cool just the northern hemisphere, the Sahel dries out very badly. If you cool just the south, it gets a lot wetter, and plant life there (as measured by net primary productivity in vegetation models) does peculiarly nicely. This is apparently due to movements of the intertropical convergence zone, the line where the northern and southern hemisphere trade winds meet. If you cool one hemisphere, the ITCZ gets pushed towards the other. If the ITCZ moves south after a northern cooling, less moisture gets from the Gulf of Guinea to the Sahel, and dry times ensue. (This is, as I understand it, on top of a generic tendency of this sort of geoengineering to dampen monsoon circulations, at least in the short run, by cooling the land more than the sea.)

This fits with the twentieth century record. Three of the four worst drought years in the Sahel followed volcanic eruptions which put lots of sulphate into the stratosphere in the northern hemisphere but not the southern hemisphere (if the gunk starts off far enough north, very little gets over the equator) and thus cooled the north but not the south. Volcanic eruptions in the south — such as Agung, in 1963, which cooled only the southern hemisphere — and near the equator — such as Pinatubo, in 1991, which cooled bothe hemispheres — did not have the same effect.

It all sounds like a pretty coherent story. A number of different model runs simulating both single-hemisphere geoengineering and various volcanic eruptions show the drying of the Sahel following northern cooling. A fairly straightforward mechanism accounts for why this might be. The historical record seems consistent with it. Is it a sure thing? no. Is it the way to bet on current knowledge? Yes. If a large volcano significantly north of the equator erupts, it seems that theres a good chance of a subsequent drought in the Sahel.*

So what does this mean for geoengineering? One implication is that climate geoengineering deployed in just the northern hemisphere looks like a very bad idea. Programmes in just the north have been considered and studied, in part because of the worries people have about something suddenly going wrong in the Arctic, something that needs “fixing” quickly. This research makes such approaches look dangerous.

More interesting, and more novel, is the implication that geoengineering might be used to avert a Sahelian drought caused by a volcano. If the stratospheric sulphates released in a major northern eruption were promptly countered by a deliberate release of sulphates into the southern hemisphere, both hemispheres would cool. The ITCZ would stay put, and a drought might well be averted. For a major drought, that would be a big win. The drought in the 1980s, which followed on the 1982 eruption of El Chichon in Mexico, killed about a quarter of a million people and turned millions more into refugees.

One way to think about such an intervention is that it would turn the hemispherically asymmetric effects of an eruption like that of El Chichon into the global effects of an eruption like that of Pinatubo in 1991. Pinatubo was a bigger eruption in terms of the overall amount of emissions, and it had various measurable effects, some of them disturbing (drop in stratospheric ozone, slowing of the global hydrological cycle). But if El Chichon did indeed cause, or help cause, the Sahelian drought of the 1980s then its effects were a lot worse.**

And if the Earth is left to its own devices, such droughts will happen again. Last century there were two eruptions that cooled the north and were followed by drought in the Sahel. The north is better endowed with volcanoes than the south, since the Pacific “ring of fire” is more a horseshoe of fire, with a gap in the south but a continuous arc in the north. The odds of at least one eruption in the Pinatubo-to-Krakatoa range somewhere of the Earth in this century are better than even. The chances of one happening in the north are obviously lower; but the odds are hardly long.

If humans had had the technological wherewithal to stop the 1980s Sahel drought in its tracks, would people have wanted to use it? It seems likely that there would have been a constituency for it, not least in the Sahel. And many of the reasons people have for objecting to geoengineering as an inappropriate “technical fix” to man-made climate change might apply with rather less force if the technology was being used to forestall a natural disaster on a continental scale.

That said, to balance out a large eruption is not really something to be attempted from a standing start. The hardware needed to lift millions of tonnes of sulphur into the sky could not be whistled up on the fly. And some of the arguments against embarking on geoengineering in a rush that I made at the top of this post would clearly apply.

But what if one were already in the climate geoengineering business, with a fleet of aircraft (or balloons, or whatever) dedicated to maintaining a permanent stratospheric haze at all latitudes? Then things might look rather different. Stopping operations in the northern hemisphere and upping them in the south might be quite feasible. This might well also be the case for other geoengineering techniques, such as the brightening of marine clouds. Providing more brightening, and thus cooling, in the Atlantic Ocean off Namibia might also be a way of keeping the ITCZ put in the aftermath of a large northern eruption.

Climate geoengineering programmes that work by reducing sunlight would have to be designed to take account of the fact that there are occasionally large volcanic eruptions. This work strongly suggests that one of the ways they should be taken into account is by the development of contingency plans aimed at balancing out their hemispheric effects, if any. If such a balancing mechanism existed, there seems to be a real chance that it could avert a major drought in the Sahel next time a big volcano pops off in the north.

That is not in itself an unanswerable argument for such a scheme. There are other ways of dealing with droughts (though they didn’t work all that well in the Sahel in the 1980s). And people might well think there are issues that should weigh more heavily in deliberations about climate geoengineering than a theoretical ability to counteract some sorts of natural disaster.

But if it is not an unanswerable argument in favour of such a scheme, it seems to me that it is a new and interesting one. A world with geoengineering in it often seems, in our imaginations, a more fragile one. In this particular respect, though, such a world might have a new resilience.

–

* There are other factors at play, including the possibility that cooling of the northern hemisphere by industrial aerosols was playing a role in the 1980s; there’s also a possible role for El Nino. But the first order story seems pretty plausible.

**Some may think at this point that there could be an argument for a permanently asymmetric geoengineering scheme designed to cool the south, push the ITCZ north, and make the Sahel wetter and more productive. There may indeed be attractions to such an idea. But there would be worries, too. In the Met Office models the sort of changes that bring moisture to the Sahel in this way reduce rainfall in north-eastern Brazil. Though it is my understanding that Met Office models have a history of being more prone than others to predict drought in north-eastern Brazil, that is something one would want to worry about a lot. Moving the ITCZ would also, I think, make a difference to the formation of hurricanes in the mid Atlantic. In general, many people might find find an intervention aimed at keeping the ITCZ in its customary place more acceptable than one aimed at permanently moving it to a specific group’s advantage and the possible detriment of others.

The column is on CCS, and in particular the new Summit energy plant outside Odessa, the Texas Clean Energy Project. Like Mr Nocera, I quite like the TCEP. Unlike Mr Nocera, I don’t think that in and of itself it provides a reason for thinking that CCS is going to be a big part of emissions reduction.

That, though, was not the part of the article which stood out. The part which stood out was:

A reduction of carbon emissions from Chinese power plants would do far more to help reverse climate change than — dare I say it? — blocking the Keystone XL oil pipeline.

For some people the naffness of that “dare I say it” will be the unacceptable part of that sentence, and for others it will indeed be the slight on the importance of the issue that a great many American greens seem to have decided is the most important battle to be fighting. To me, though, the problem is that Mr Nocera seems to believe that reducing emissions would mean reversing climate change. It wouldn’t. Emissions increase the carbon dioxide level. Higher carbon dioxide levels lead to more warming (people of good will, and others, can disagree about how much more). Reduce emissions appreciably and you slow the rise in the carbon dioxide level, which should reduce the rate of warming. But to reverse climate change you have to either bring the carbon dioxide level down or cut the amount of sunlight warming the earth in the first place. If you don’t understand the difference between reducing and reversing I don’t think you should be writing about this subject. Or for that matter driving a car.

The main point of Mr Nocera’s column seems to be to pick a fight with Bill McKibben. Fair enough. I have wanted to do so, on different grounds, many times. Who knows — maybe one day I will. But when I do I will try and show a slightly better grasp of the basics.

I’d like to preface this by saying that I am a big fan of Anne Thompson and Kris Tapley’s Oscar-race podcast. It has just the sort of insider-knowledge-pitched-slightly-over-my-head vibe that I like in conversational podcasting. The general respect and affection in their relationship is given spice by just the right amount of with occasional needle and crossness. I like Anne hitting the table (at least I assume that’s what she’s doing). And most of the time it seems to me to have just the right balance on the question of whether taking the Oscars seriously is silly or not.

But I have to take exception to what they say on statistical approaches to predicting Oscar outcomes about seven minutes in to their post-Oscar post mortem. Noting but dismissing the predictions at Fivethirtyeight.com, we have the following exchange:

Anne: He got a lot of his predictions wrong because it was a very crude system he was using

Kris: There’s no way to Nate Silver this kind of thing

Anne: Exactly– you have to have a little bit of knowledge, experience, intuition — [to] see the movies, talk to people, you know — what we do for a living is required.

The evidence this year, though, suggests that there are ways to Nate Silver this kind of thing — that is, to come up with a good prediction based simply on the data available and statistical models based on past races.  Let’s compare the results from the “Gurus o’ Gold“, a college of 14 Oscar predictors to which Anne and Kris belong, with the results from a statistical model put together by Ben Zauzmer, a student at Harvard.

Ben used his statistics to predict the results of 21 of the 24 races. He got 4 wrong. If you look at the aggregate results for the gurus in the same 4 races, they got 5 wrong. Looking at the gurus individually, I count 4 who did better than Ben on this subset (including Anne), and 8 who did worse (including Kris).

If you want to make Zauzmer’s stats look worse, then look at the whole field of 24 awards. Ben didn’t make predictions in the categories of documentary short, live action short and animated short categories because he doesn’t think the data are strong enough. If you count this failure to engage as getting the results wrong Ben gets seven mistakes out of 24. The gurus have five out of 24. But look at the gurus individually and six did better than Ben (including Anne and Kris), six did worse. So even on the less charitable interpretation of what he achieved, he’s right in the middle of  the pack.

If by “Nate Silver-ing” you mean calling every race accurately then no, you can’t Nate Silver the Oscars, or at least no one has managed it yet. But the idea that you need to have a lot of insight or insider knowledge to do as well as the people who are best at it doesn’t seem to wash. An outsider with data and stats can, it seems, do as good a job as reporters doing it for a living.

By pointing this out, though, I do not for a moment mean to suggest that Anne and Kris should pack up shop. The results of a race matter, for sure — but so does, like, the race. Things being overtaken, leads stretching out, resources being squandered or carefully husbanded — that’s what’s fun to watch. And in this case, for me, there’s a bonus in the insights into what matters to film people and what is seen, and not seen, as working. Not to mention gossip. The stats don’t give narrative or context or tangential insights, and that’s what interests me, much more than the final results. I will be listening to Anne and Kris again next year. But that doesn’t mean that, on the home straight, stats aren’t as good as most gurus and better than quite a few — and the gurus might get better if they acknowledged that.

National Geographic has a nice, evocative piece about leaves by Rob Dunn (@RobDunn) along with a typically beautiful gallery. This particular image is by Carsten Peter (@carsten_peter)

One of the reasons I haven’t actually written about this is that I’m not quite sure what this says about the world. I’m putting up this sort of placeholder, though, because I was struck by what Paul McAuley has to say about it means for science fiction in this excellent blog post on the distinctions people make between literary and genre fiction.

Too much science fiction looks ‘inward’, but I wouldn’t make a strong distinction between science fiction that attempts to revitalise genre tropes and science fiction that attempts to inject new ideas for ‘outside’; some of those tropes have escaped into the real world, and by engaging with them and using them to discover new meanings science fiction is in dialogue with both its own ideas and with the real.

That’s very true of Paul’s work: his The Secret of Life, for example, is a dialogue between science fiction staples (life on mars) and the real world (an ever more commercialised biology); The Quiet War is about what green politics could mean long term as well as dogfights in the rings of Saturn. The bravura “invasive species” moment in Kim Stanley Robinson’s 2312 brilliantly plays a staple of science fiction off against real-world ecological concern. These are exciting ways that science fiction can deal with the fact that some of its traditional subject matters are now part of the reality of the world — in Paul’s words,

laying the groundwork for all kinds of debates that stimulate writers and readers, and refresh the field and widen its possibilities, and crack open the limitations and boundaries (too often self-imposed) that, according to critics like Krystal, consign genre fiction to the outer dark of the second-rate.

So science fiction has ways to deal with the fact that it has infected/invaded/annexed the real world, and Paul is clearly right that the prospect of using and developing those means is an exciting one. But it’s not yet clear that the real world has good ways of talking about the fact that it is in part science fictional, which is the deficit that I really want to address.

As the first man to walk on another world, Armstrong received the lion’s share of the adulation. All the while, he quietly insisted that the popular image of the hard-charging astronaut braving mortal danger the way other men might brave a trip to the dentist was exaggerated. “For heaven’s sake, I loathe danger,” he told one interviewer before his fateful flight. Done properly, he opined, spaceflight ought to be no more dangerous than mixing a milkshake.

Indeed, the popular image of the “right stuff” possessed by the astronaut corps—the bravery, the competitiveness, the swaggering machismo—was never the full story. The symbol of the test-pilot school at Edwards Air Force Base in the Mojave desert, where Armstrong spent years testing military jets, is a slide rule over a stylised fighter jet. In an address to America’s National Press Club in 2000, Armstrong offered the following self-portrait: “I am, and ever will be, a white-socks, pocket-protector, nerdy engineer, born under the second law of thermodynamics, steeped in steam tables, in love with free-body diagrams, transformed by Laplace and propelled by compressible flow.

Particularly grateful for the nuance he brings to the notion of “The right stuff”, which many others failed to bring out. It’s a complex and layered book, and far from a simple paean.

Clive Crook’s response struck, unusually for Clive, a personal tone. In general, I was struck by how many memories people were blogging and tweeting were about their fathers.

When it came to what NASA accomplished, [my father's] admiration turned to awe. It makes me chuckle even now to think back to it. This reverence was so unlike him. He wanted me to understand just how difficult a thing it was–and how daring. “I know you think it’s incredibly hard, but it’s so much harder than that.” He followed the engineering as closely as he could and explained a lot of it to me. He persuaded me so well that I secretly decided it couldn’t actually be done. The margins for error were just too small. I was sure something would go wrong and they’d fail. Of course we stayed up all night and watched the video of the first walk on the surface. We were both moved to tears.

Neil Gaiman posted this picture, which is not just great fun but also seems to capture a particular happiness on Mr Armstrong’s part.

And Roz Kaveney was, as always, inimitable

Endymion – for Neil Armstrong

In her white silent place, the hangings dust,
grey pebbles stretching to the edge of black
so far away. The goddess feels a lack
somewhere elsewhere, an ache deep as her crust

and weeps dry tears. The gentleman is gone
the first who ever called. His feet were light
as he danced on her. Went into the night
quite soon, his calling and his mission done

yet still his marks remain. Footfalls and flag.
The others she forgets. He was the first
to slake her ages long and lonely thirst
for suitors. Now she feels the years drag

as they did not before he came to call.
Our grief compared to hers weighs naught at all.

I have little to add. He was clearly a magnificent man, and, as Tim notes, one who would never have dreamed of trying to take credit for the remarkable political and technological instrumentality that took him so high into the sky. Many mourning his passing mourn the passing of  that instrumentality, too, and would wish it revived. It is a feeling that I understand, though less well than once I did, but cannot share. It does no disservice to Mr Armstrong’s memory to believe, as I have come to, that now is not the time to try and recapitulate those achievements, nor to try and surpass them with similar feats of human space exploration.

And if you feel worried about giving up the honour that goes with the next landing on the moon to the Chinese, remember that their envoy has already been there. The process that sent him there might have been deeply rooted in the cold war: but Neil Armstrong really did come in peace for all mankind.

So here’s an image to try and capture the immensity of the flow in which we are embedded. Picture Horseshoe Falls, the most familiar, forceful and dramatic cataract in Niagara Falls, in full spate.

Now increase the height of the falls by a factor of 20; a kilometre of falling water, a cascade higher even than Angel Falls in Venezuela.

Now increase the flow by a factor of 10. Instead of 30 tonnes of water falling over each metre of the lip of the falls every second, allow 300 tonnes of water per metre.

Finally, widen the falls. Stretch them until they span a continent, with billions of tonnes of water falling over them every second. And don’t stop there. Go on widening them until they stretch all around the equator: a kilometre-high wall of water thundering down incessantly, cutting the world in half, deafening leviathan in the abyss.

That is what 120,000 terawatts looks like. That is what drives the world in which you live.

However the fact that a personal subscription to Nature does not allow you access to its archive is simply crappy.

Yes, you get access to articles back to 1997, which is better than nothing. But science didn’t start in 1997. Nature didn’t start in 1997. Ideas that are important today are not all rooted in the very shallow post-1997 horizon of intellectual history. The random selection of articles I just looked at  in a recent issue all had references to pre-1997 work, some of it published in Nature.

Sometimes pre-1997 observations are as current as they come. Today I was looking into various aspects of the Pinatubo eruption of 1991. Around the world scientists looked into the eruption and sent their observations and ideas to Nature. The best of them got published. Have there been any better observations since? No – there haven’t been any comparable eruptions to observe since. So I can’t read the most recent relevant observations on a topic of current interest  in a journal to which I have paid to subscribe.

Not an isolated instance. A friend recently asked me about the origin of a fundamental concept in molecular biology. With a little work, I tracked it down to a Nature paper from the 1960s. That was helpful to him — but I couldn’t get the full context because I couldn’t get the bloody paper. (The friend could – irony of ironies, he works for Nature.)

I admit that I’m probably unusual in the amount of pre-1997 stuff that I want to read.  I have a greater interest in the roots of scientific discussions than most. I am interested in the continuities and lack of same between science now and science in its past. I like the day before yesterday.

But a) I think, all other things being equal, it would be better if more people moved a little way towards my approach to these things. Too many people read only the most recent publications in their field, and lack a long perspective.

And b) I BOUGHT A SUBSCRIPTION. I should be able to read the archive.

Now, I should note that this policy, while stupid, is not sneaky. The subscription page makes it clear that you don’t get the archive. And I should also note that the subscription is worth it anyway for a beautifully produced magazine that never fails to inform and fascinate.

But it is still a bad policy. And not just because it inconveniences me and leaves me feeling ripped off by an institution I esteem so highly. Because Nature should be about all of Nature. It should be about making you a part of the process of which it is, and has been, a great exemplar. And it shouldn’t salami slice that process in search of a quick buck.

I remember speaking with quite fierce pride at my leaving party about the experience of being at the head of a spear  with a haft centuries long behind it. But if you want to appreciate the haft, it will cost you £22 quid a glimpse, even if you’re a paid up member of the spearhead. That’s wrong. If you’re part of Nature‘s wonderful ongoing conversation you should be part of all of Nature‘s wonderful ongoing conversation.

By the 1960s, two distinct ‘environmental sciences’ had emerged: one biology-centered, focused on the problems in ecology and population studies, and funded in part on the problems in ecology and population studies, and funded in part by agencies and managers concerned about human threats to the environment; the other geophysics-centered, focused on the physical environment, and responsive to the operational needs of the military services that support it.

I can see that, and I can see how it would map in part on to a distinction between critical and industrialised science of the sort that Ravetz discusses.

But here’s a different dichotomy, in a different context, as ascribed to G. Evelyn Hutchinson by Joel Hagen in “An Entangled Bank”

Population biologists tended to take a merological perspective, focusing upon independent individuals and assuming that population phenomena determined higher level community properties. In contrast to this bottom up approach, other ecologists, particularly those who later studied ecosystems, took a holological approach by studying the flow of materials and energy through food webs without considering the individuals that made up the web. Hutchinson, an eclectic biologist, seemed capable of making the transition from one perspective to the other effortlessly. Most other ecologists have not been so adept.

And this, it seems to me, also bears on the Clements/Tansley dispute, as to whether there was a sort of teleological holism in ecology (the notion of the climax ecosystem), or simply sets of relations between populations and their physical environments which could be studied rather as those in physics could be.

Now it’s pretty clear to me that these aren’t all the same cut and dried dichotomy. You can be a military-linked energy-flow kind of guy and believe in climax systems (I think the Odums did this). But elements of it do seem to be consistent. I wonder if anyone can guide me to deeper thought on this?