Gifts to Greece

My first thought this morning was to write about the so-called UK drought again. Maybe I’ll post something on that later.

Then I had a strong urge to comment on the absurdly excessive punishment of Lewis Hamilton (a 5 place penalty or inadmission of his final run – moreorless equivalent punishments – would have been appropriate) after an error by his team in qualifying for today’s Spanish GP. I’d hardly call myself an expert on the sport, but a previous foray into F1 commentary attracted a good deal of attention.

Instead I’m going to channel my annoyance at the spoiling of what might have vaguely resembled a sporting event in Barcelona towards the Greeks.

All I want to convey is one simple point, that the Greek people have benefited hugely from the international loans on which they have already partially defaulted and look increasingly like failing to repay in their entirety.

We haven’t invented this thing we call money just for fun. Money allows resources to be allocated. If you borrow it, spend it and fail to repay the loan, you have acquired or consumed resources that could have been used by someone else. Take the Athens metro railway and all the other billions worth of infrastructure to support the 2004 Olympic Games. How was that funded? I’ll hazard a guess. Borrowed money, at least in part. And what will happen to all that capital investment when Greece defaults? It’ll still be there. These assets will remain in existence indefinitely for the benefit of the Greek people. To the extent they haven’t been paid for, they’ve effectively been stolen from the rest of the world.

Some loans may be riskier than others, because that’s how the world is, but, unlike equity investments, loans are designed to be repaid. Financial disruption – on a global scale over the last 5 years – arises when debts are not repaid. So, because of the knock-on effects, Greece’s default is worse than theft! The entire EU has been plunged into recession in large part because of the need for the financial system to prepare for possible Greek default. Instead of using capital to support new lending, banks have been writing down Greek (and other) debt and taking actual losses.

Obviously we’re just reaping what was sown when Greece and other European sovereigns borrowed unsustainably. The question is how to prevent repeats of this cycle of behaviour?

Let’s mull over that question for a minute. What is the popular conception of what’s going on?

I think it was Arthur Smith I heard on the radio yesterday saying the Greeks should be let off their debts because “it’s not the fault” of those protesting. In what sense is that, Arthur? Are you perhaps saying the average Greek took no executive decisions regarding the nation’s finances? Clearly true. But isn’t a large part of the problem that they haven’t paid and continue not to pay their taxes? What do you think is fairer, that every Greek homeowner should pay a special tax (they’re refusing) or that you and I should find the money?

And isn’t a large part of the problem the Greek public-sector? What do you think is fairer, that Greek workers should take whatever pay cuts it takes to balance the books (as has happened elsewhere in Europe, such as in Estonia – now growing again – Latvia and Lithuania) or that you and I should find the money?

Many non-wealthy Greeks must also be culpable of wilfully participating in a cash economy, benefiting from lower prices for services whilst complicit in tax avoidance. What do you think is fairer, that the Greeks start paying taxes commensurate with their public spending like people in most other countries, or that you and I should find the money?

But the really interesting point is that Greece is a democracy. They’ve chosen their own government since the ousting of the colonels in the 1970s. Collectively, then, they’ve repeatedly elected politicians, at least some of which have overspent, undertaxed and cooked the books, or appointed officials to do so on their behalf. Clearly, collectively, the Greeks have benefited from this behaviour. I’m intrigued, Arthur, whether you’re suggesting that, collectively, the Greek people are also not responsible for the situation they find themselves in.

That’s probably enough. After all, Arthur is a national treasure, practically the new Queen Mother, and perhaps a little fragile. Maybe he just didn’t think. Maybe, like the QM, he inhabits a world where decisions are made by waving a magic wand. Maybe, like the QM, he lives in a world where one need take no responsibility for one’s finances.

I also caught a snippet this morning of someone on the Andrew Marr Show invoking the precedent of Argentina. That great and honourable country, that upstanding, exemplary member of the international community most recently defaulted on their debts about a decade ago. And it’s been great for their economy! Who’d have thought it? It’d be great for my personal finances if I went out and bought a house, a car, new furnishings and white goods, new shoes, clothes and so on and then didn’t bother paying for them. I’m sure I’d feel pretty well off for a few years too.

Let’s pick on someone else. Arianna Huffington writes in the NYT:

“Yes, the Greeks acted irresponsibly before the economic collapse — the same way my father had acted irresponsibly in his private and professional life. But that is not reason to punish the children, to destroy their future as part of a remedy for a past for which they bear no responsibility.”

What Arianna is saying – for some reason “bleeding heart liberal” is the outmoded phrase that comes to mind – is a little more sophisticated than Arthur Smith’s indignant genialism. We have to draw a line, she says, to protect the innocent. Though, I can’t help pointing out yet again, these “innocent” are nevertheless beneficiaries of the misappropriated funds spent in Greece over the last decade or so. Perhaps they’ll remember that every time they hop on Athens’ shiny new metro trains.

The fear gripping financial markets – and contributing to the unnecessary economic hardship and suffering of innocent little children currently taking place in, say, the UK – is that other countries will follow Arianna’s line of reasoning too. Why shouldn’t Ireland, Spain, Portugal and even Italy say “don’t punish the children”? Having elected profligate, irresponsible governments that have given them what they wanted – low taxes, high spending – why won’t they now elect governments to satisfy their new desire for debt writeoff with some kind of moral justification (right wing nationalist or left wing anti-capitalist – take your pick, or, hey, what the hell, you can even pick both!).

If we want financial stability – quite possibly a good thing, I suggest, in light of the 1930s, just as a for example – then debts have to be repaid. And sovereign debts would be a good start.

So how can the international community protect itself against freeloaders? Against those countries who run up debts, fail to collect enough tax and then, in the words of the song about the girl next door and the bathroom floor, plead “It Wasn’t Me”?

Here’s my suggestion. Many of the countries that default are serial offenders. There’s something deeply ingrained, in their DNA if you like, that leads them to spend too much and collect too little tax. So cut them off from international finance for long enough for them to lose thir habits. This would be simple to implement. The financial services industry is highly regulated (all that effort’s been really effective, hasn’t it?). Regulators in responsible countries (say the UK, the US, the EU apart from Greece) could simply demand that no financial institution or its subsidiaries (maybe even no company) lends at all to a government that has defaulted on sovereign debt over the last 50 years – or maybe even more. Or, crucially, to any institution in that country dependent on its government, such as a bank or a company.

Since holding the currency of the defaulted country would constitute lending, all investment in defaulted countries would have to be funded locally in their own currency. Imports would require foreign currency that would have to be acquired beforehand by local institutions or individuals, i.e. by selling goods and services as exports (or small amounts of currency to tourists and other visitors). No publicly funded export credit guarantees would be available to UK companies, for example. In effect, such countries would be forbidden from running a trade deficit.

Such a measure would do two things. It would financially quarantine serial defaulters for a time longer than short-term market memory currently manages (defaulters tend to return to the international markets within a decade). And it would give non-defaulters pause for thought.

Don’t Backslide on Greece!

You know there’s serious trouble when the Economist runs a two-page editorial, in this case proposing “how to save the euro”.

The Economist agrees with most observers that the problem boils down to how to deal with Greece.

Let’s recap.  Greece, a serial defaulter, essentially fiddled the books to understate its debt in order to be admitted to the euro club, hoping for more economic stability.  Then the financial crisis came, and, as the saying goes, the tide went out and the Greeks were seen to be wearing no trunks.  Not only that, there was an Aegean tsunami on the horizon. Luckily, the Germans had grabbed the deck-chairs so the Greeks aren’t on their own.

What are the Greeks, the Germans and the eurocrats (not to mention the IMF) to do?

What baffles me is the current hysteria from all quarters. Decisive action is not required, as for example, George Osborne insists. The Greek debt is a long-term problem which requires a long-term solution. “Decisive action” implies some kind of quick fix. “Decisive action” is the last thing we need.

In fact, I can see things that can be done to mitigate the situation – economic stimulus measures in the less-indebted eurozone, other European (that includes the UK, Mr Osborne) and other global economies – but I simply can’t see how the central problem could be handled any better than it already is. If that’s not what the markets want to hear then the markets will just have to get over themselves. Some problems just have to be lived with.

Let’s consider the alternatives (I’ve previously written about this on Martin Wolf’s blog at the FT, but I can’t even access that right now, as I terminated my FT subscription in protest at them trying to jack up the price).

1. Greece exits the euro and devalues
This would be catastrophic, at least in the short-term. The Economist discusses the possibility and quotes an estimate that such a step would cost Greece 40-50% of its GDP in the first year (though this seems to assume they leave the EU as well). The trouble is, the “mother of all financial crises” that would result would not be confined to Greece. French and other eurozone banks would take a massive hit, with all kinds of knock-on effects. Even if the initial shock could be contained without seriously recessionary consequences for the remaining eurozone countries, it would simply be a case of “who’s next?” – Ireland, Portugal, Spain, Italy, Belgium, France…

2. Greece devalues within the euro
This is the straw that many are now clinging to, including the Economist, but in fact it’s almost as bad as option 1.

First, there’s the moral argument. Why should the beneficiaries of excessive Greek borrowing be forgiven their debts? Greek taxpayers (or non-payers, by all accounts) would escape paying taxes equivalent to the nation’s long-term spending; all Greeks would have benefited from public services that they haven’t fully paid for; Greek public sector workers would have been paid more than the nation could actually afford – the list is endless. The point is, although different Greek constituencies would no doubt blame each other, the entire nation is complicit, though pre-school children can legitimately claim not to have been in a position to influence matters overmuch.

Second, if Greece is let off a large chunk of its debt, why wouldn’t other countries demand the same? Why should the Portuguese, Spanish, Italians, Irish, French and Belgians suffer tax rises and cuts to their public services if Greek debt is simply written down?

Third, and critically, there’s the problem that a Greek default within the euro doesn’t actually solve the underlying problem. It does something about the debt, but not the deficit. If Greek debt is (say) halved from around 140% of GDP to around 70%, they will still not be credit-worthy, because they’d still be running a deficit. There would still be a need for the IMF, EU and ECB troika to help the Greek government somehow bring revenue and expenditure into line. There’d still be a need for wealthy Greeks to pay more taxes, the Greek public sector to spend less and its economy somehow to grow. In the meantime there’d still be a need for someone to lend euros to Greece.

A Greek default within the euro would simply not have the usual effect of sovereign defaults because it would not be accompanied by devaluation.

In fact, the main effect of Greek default within the euro would be for the Greeks to say “thank you very much”. There’d still be a big hit on eurozone banks (including the Greek ones which would need to be recapitalised from somewhere, and not to mention the ECB), although not the automatic loss from lending to the Greek private sector that would occur in the case of option 1 (when devaluation would make it more difficult, to say the least, for Greek companies to service euro-denominated debt).

Now, it seems to me the troika must recognise this. If I was them I’d demand the budget reforms before allowing any kind of Greek default. In particular, the possibility of Greece having to leave the euro needs to be still on the table. In fact, it wouldn’t surprise me if there hasn’t been a nod and a wink to the off-message officials and politicians (usually German) who regularly float this possibility.

It seems the next payment to Greece is being put off to the last possible moment, even though stumping up is much better for everyone than the alternatives. What puzzles me is that the markets don’t recognise that this brinkmanship is a necessary part of the strategy of forcing Greece to balance its budget in the long-term.

What the Greeks should really be worrying about is the possibility that they haven’t resolved their fiscal problems by the time the rest of the eurozone has recovered (and in particular the banking sector has rebuilt its capital) sufficiently to withstand a Greek default, euro exit and devaluation. Then the eurocrats might just decide to throw them to the wolves.

Still, I wouldn’t rule out a collective loss of nerve and a Greek default within the euro. We’d have to muddle through somehow. If there’s a double-dip, there’s a double-dip – maybe that’s now the least we can expect; if there are further sovereign defaults, the sun will still come up the next morning; if we do end up calling it the Second Great Depression or a Lost Decade, life will still go on. As I said, some problems just have to be lived with.

Uncertain about Risk and Uncertainty

Here’s an interesting – nay, potentially iconic – figure from a paper, Greenhouse-gas emission targets for limiting global warming to 2C, Meinshausen et al, Nature vol.458, p.1158, 30th April 2009:

It represents the results of a heroic assemblage of climate modelling data. The horizontal axis gives the emissions from 2000-49 (belying the paper’s title, incidentally) in GtCO2 for each set of data plotted and the vertical axis – careful wording alert – the probability of the given model output set predicting a global mean temperature increase of 2C or greater over pre-industrial levels before 2100. The dots and swathe of colour are the outputs of all this modelling; the solid black line some kind of best fit (I know not how determined) or “illustrative default”; the dotted line incidentally is the outcome based on a set of models including carbon cycle feedbacks, which implies less likelihood (carefully chosen word) of hitting 2C for given fossil fuel and land-use change emissions.

The good news is that if this modelling exercise represented a set of real world possibilities, we could, for example, emit around 1500GtC02 and still have a 50% chance of avoiding “dangerous climate change” defined as the 2C temperature increase. The bad news is that the grey area bottom left of the figure represents the 234GtC02 of actual emissions from 2000-06 (7 rather than 6 years, I believe, though the paper is scandalously ambiguous on this point) – basically we have to slow way down.

You could probably write a dissertation about the diagram – for example, why are we discussing scenarios for the future such as the IPCC’s A1F1 (top right) which apparently emit more carbon before 2050 than is stored in the world’s fossil fuel reserves (and even more in the second half of the century)? In fact, why are we discussing more than one of the IPCC scenarios, since even the best of them, B1, is unlikely to lead to less than 2C warming? There is surely no longer any need to nuance the basic point that unmitigated emissions will lead to dangerous climate change.

But all I want to cover just now is essentially one word. The word “probability” on the vertical axis.

What we have here are not probabilities in any real-world sense. There will only be one outcome. We will be at one position on the horizontal axis, depending on (in this case) our emissions before 2050 (though different pathways may give different outcomes for the same 2000-49 emissions). The distribution about the illustrative default (a vertical slice through the diagram) is an indication of our state of knowledge (as encapsulated by the models used) as to what will happen to the global mean temperature as a result. It is not, in a strict sense, a probability.

Using the term probability in this context is unfortunate. In fact, I might even go so far as to say it is symptomatic of a pathology: the same pathology evident when the idea of carrying out climate “experiments” is discussed. Guys, we are using models, not instances of the real world. If parallel universes do exist, we do not have access to them.

My personal issue with all this is that when I read the word “probability” I assume we’re talking about risk, when in fact the topic is uncertainty. I simply can’t help it.

It is extremely unfortunate that the climate modelling community (and perhaps a wider group) has chosen to use the word “probability” to refer to uncertainty as well as risk when they could simply have used “likelihood”. This has been extended to probability distribution functions (PDFs) which are often nothing of the sort (I say “often”, because, confusingly, the horizontal axis may be a probability function and the vertical axis what I would call a likelihood function). These figures should be renamed likelihood distribution functions, with the added advantage of a less overused TLA, LDF rather than PDF.

Apart from confusing models with the real world, the inappropriate use of the term “probability” has caused another problem: too much weight is being given to quantifiable knowledge (included in models) and too little to that which has not been quantified. The term “likelihood” would instead force people to focus on the right questions. What’s happened is that the climate science community is pretending it can somehow answer epistemological questions – those about the state of knowledge – in a scientific, quantifiable way. Presenting the information in precise terms – “my belief in the actual increase in the global mean temperature we can expect for 1500GtC02 emissions is represented by this graph” – doesn’t alter the fact that all we are discussing is the state of our knowledge. And when we let machines produce the graph we automatically lose anything not input to the calculation.

I thought I’d try to clarify the problem with a simple analogy.

If I toss a coin and call “heads” the probability – risk – of losing is approximately 50%. I can make decisions on this basis.

But I said “approximately”, because there is some uncertainty – the coin may have a bias.

Now, any estimate of uncertainty in this case depends entirely on my state of knowledge. For example, I might have tested the coin – suspecting it might be weighted – before the crucial coin toss and found that of hundreds of attempts 55% came up heads. This (and my knowledge of statistical confidence testing) may then lead me to believe the risk of losing to be not 50% but 45%. But this would be exceptional. For a randomly chosen coin I would normally be prepared to say it’s likely – an expression of certainty – that the risk of losing when calling heads is, for all practical purposes, 50%.

If asked to quantify how sure I am that the risk of losing is 50%, I might say 99.99%, because I believe the vast majority of the coins in circulation are equally likely to come down heads as tails. But this 99.99% is what I would term a likelihood – a judgement of the uncertainty – not a probability.

On the other hand I may be asked to pick a coin from a bag I’m told contains 50 normal coins and 50 weighted so as to come down heads only 25% of the time. Now it becomes a probability as to how likely it is that the coin is true. I can even calculate the overall probability of tossing a head (37.5%). There may still be uncertainty, though – whoever told me 50% of the coins are weighted might have been lying.

What I hope this analogy conveys is the importance of being clear about what we know and what we don’t know. We should only talk about risk and probabilities within a defined theoretical framework. When making judgements as to the state of our knowledge we should be discussing uncertainty and (I suggest) likelihood.

Let’s turn back to the iconic figure from Meinshausen et al and that vertical axis labelled “probability”.

Are we really talking about probability or likelihood?

Remember where the numbers come from – a series of computer model runs. Here’s a philosophical point: no scientific model is the same as the real world. A simple scientific law such as F=ma or E=mc2 may make very good predictions, but has different characteristics to the real world. And these simple models give the same answer every time (or rather, are not sensitive to small variations in the initial conditions). When we use complex computer-based models such as of climate, we find that quite different answers result from multiple runs with minimally perturbed initial conditions.

What we don’t know is how much of the variation in model runs depends on a lack of determinism of the real world and how much is a result of the characteristics of the models. Remember the real world is air, water, sunlight, clouds and so on. The model is numbers representing big chunks of real stuff in a computer. Maybe there is a “butterfly effect” and the magnitude of global warming in a century’s time will depend on minor unpredictable events that happen today. Somehow I doubt it – weather may be affected by small events, but not climate – though the issue could be discussed long into the night.

What is less disputable, though, is that we don’t know how much of the variation in model predictions of global warming is due to different real world possibilities and how much is due to the characteristics of the models.

By failing to distinguish probability from what I term likelihood, and labelling their vertical axis as “probability”, papers such as Meinshausen et al are perhaps implicitly asserting that what is represented is entirely due to real world variability.

It seems to me far wiser to do the opposite. We should assume that the variability of model outputs represents uncertainty. We are best off considering that if the models were perfect they’d give the same answer every time.

But Meinshausen et al might argue that all they’ve done is use the word “probability” loosely. They might agree with my argument. Now, though, we have another problem. We are giving much more weight to model variability than to other forms of uncertainty. The models only capture some of the known unknowns. There are known real-world phenomena that are not included in the models – poorly understood phenomena, for example, carbon-cycle feedbacks, such as methane release from tundra. And then there are unknown unknowns.

Here’s my biggest problem – if we are to present some forms of uncertainty in numeric form then surely we are obliged to present all forms of uncertainty in the same way. It is misleading to simply list the things we haven’t taken account of. We have to make judgements about the known unknowns and unknown unknowns and adjust the uncertainty distribution accordingly. It’s not all bad news: we might argue that the models overstate the uncertainty in outcome and narrow the distribution in figures such as that by Meinshausen et al.

Policymakers need a considered view of the state of climate knowledge, not diagrams that present dubious “probabilities” and a set of provisos.

Nuclear Future Unclear

Whilst pondering this piece, I saw George Monbiot has added his ha’p'orth. I don’t know if he writes his own headlines, but I can’t help noting that “Japan nuclear crisis should not carry weight in atomic energy debate” is a prescriptive statement and the real world is normative (a distinction I probably owe to Nassim Taleb, as I’m currently reading Fooled by Randomness). Lovelock has also apparently used that ill-advised word, “should”. Maybe it should not carry weight, but it will. In fact it already has, since countries from China and India to Germany and France are reviewing their nuclear plans.  At the very least, increased safety compliance costs will be imposed on nuclear energy suppliers.

As I write things look grim. The Japanese Emperor has prepared the nation, the head of the IAEA is flying in, global stock-markets are in freefall and even the UK is politely advising nationals to “consider” leaving the Tokyo area. Russian and EU energy officials have described the current status as “worst-case scenario” and “out of control” respectively.

Maybe the Fukushima plant will by some miracle be pulled back from the brink. But the problem – as discussed in a comment on The Climate Philosopher‘s blog – is that there are now multiple interacting problems. Radiation levels are preventing access to the site and there is contention for the available resources of water, equipment and personnel.  And last-ditch measures – dropping water from helicopters and using water cannon – are being adopted to try to cool parts of the complex. Sometimes a solution presents itself in a crisis, but because there are so many problems at Fukushima, it’ll take more than a calm, clear-headed, courageous individual to save the day, as Thomas Tuohy did at Windscale. The only real hope is that electrical power to the plant is restored allowing the electric pumps that failed in the earthquake and tsunami to be restarted. Assuming they’re still operational.

The Climate Philosopher’s initial post only considered the problem for the case of a single reactor. But as we saw yesterday (Wednesday), one event can force the evacuation of the site, stalling measures to control all 6 reactors and (at least) 2 pools of spent fuel rods, at least temporarily. It seems only a matter of time before the site has to be evacuated for an extended period. If – though I’m starting to suspect when – this happens, the other reactors will release further radiation and the spent rod cooling pools will boil away.

The cooling pools are at least as much a worry as the reactors. Apparently they could even go critical if they dry out, but more likely they’ll simply burn. They now have minimal containment, so the result is likely to be a radioactive plume, presumably not on the scale of Chelyabinsk, though in a much more densely populated region. Hopefully the wind will still be blowing out to sea if such a release does happen. It occurs to me that in some ways a single explosive event, rather than a gradual release, might be preferable, since, if the leak occurs over time, and the wind direction varies, radioactive material will be spread over a wider area. And besides the direct effects, access to the site would be further restricted.

It is now almost irrelevant how serious the situation becomes, since the risks of nuclear power have now been highlighted.  The technology may well be safe if reactors and waste storage facilities are properly designed and managed.  Location is always going to be a problem, though.  We don’t have to worry just about earthquakes and tsunamis.  Monbiot supposes we can blithely:

“…add a fifth [condition for nuclear power], which should have been there all along: no plants should be built in fault zones, on tsunami-prone coasts, on eroding seashores or those likely to be inundated before the plant has been decommissioned or any other places which are geologically unsafe. This should have been so obvious that it didn’t need spelling out.”

Trouble is, George, that rules out practically all of them, since nuclear power needs a constant supply of large quantities of water.  And not only will global warming increase flood risks, it will also lead to sea-level rises which may be significant within the lifetime of reactors being planned today.

Much has been made of the folly of the General Electric (GE) Mark 1 Boiling Water Reactor (BWR) design and so-called Generation III passive-cooled reactors are undoubtedly less risky.

But the public will still be worried.  Let’s assume the wisdom of crowds is at play and the population are not just ignorant proles.  What might the concerns be?

1. Just because we avoid what can now be seen to be obvious problems doesn’t mean we’ll avoid subtle ones in the future.  We don’t know what we don’t know.  Hindsight is a wonderful thing.

An account of the fire at Windscale suggests causal factors were not just design misjudgements that must have made sense at the time – air-cooling and a change of usage mode which meant the thermocouples became suboptimally located – but also unexpected effects, in particular the deterioration of the crystalline structure of graphite under neutron bombardment.  Who would have thought of that?  And even then the precise cause of the initiation of the fire remains obscure.

Even in the best designs there is bound to be scope for human error and unexpected physical processes.

2. We are systematically underestimating risks.

There was inevitably going to be a severe earthquake followed by a tsunami in Japan.  It was only a matter of time.

Not only that, the GE Mark 1 BWR was known to be unsafe.

Why then was this accident allowed to happen?  Even without hindsight, it would have been cheaper to scrap the Fukushima BWRs decades ago and replace them with reactors of a modern design.  The storage pools could have been made safer and separation from the reactors increased.

Here’s a clue.  I read in more than one place that the criterion for design of French reactors is based on protection against a 1000 year flood.  Sont-ils des noix?!  Are they nuts?  Here’s another thought prompted by Taleb.  If there are 1000 reactors in the world vulnerable to a variety of 1000 year risks – and let’s be charitable and assume each reactor is only vulnerable to one risk – then we can expect a nuclear crisis once a year on average!

It seems that the Fukushima complex considered only the risk of a magnitude 7 quake.  Not the worst possible.  And the tsunami was not a second disaster as many media commentators have implied.  The one caused the other.  I was struck after the 2004 Indonesian tsunami that isolated Pacific islanders, who survived by heading for the hills, explained that their ancestors had warned them that: “after the ground shakes, the sea will invade the land”.

The problem, of course is the process of risk assessment.

When I get on a plane the chance of not making it to my destination is less than one in a million.  And the public expects certainty.  Any aircraft accident near-miss results in lengthy enquiries and safety improvements of various kinds.

The possibility of an accident at a given nuclear facility needs to be reduced to at most billions to one.  Multiple levels of containment are needed to allow for the unknown unknowns.

The issue is a thorny one.  Corporate interests are involved.  There is political reluctance to write off significant investments.  Hubris and other admirable human traits play a part.

Nuclear risks are not the only ones we need to be concerned about.  Climate risks are similarly misjudged.  It’s not enough to only have to worry about 1000 year floods or droughts or heatwaves or winters.  Given (say) 100s of possible 1000 year disasters, some will occur every few years!

And then there are risks of various kinds to human health, such as epidemics, and to the economy, such as banking crises.

Dealing with the risk management deficit is a huge task, but here are a couple of recommendations:

1. A formal quantitative approach is needed.  We currently have more rather less tolerance of risks that affect many people, are  disruptive, expensive to address and that require public rather than private expenditure.   Risk levels need to reflect and be seen to reflect what the public would choose.  Otherwise political support will not be forthcoming when it is needed, such as during the nuclear plant planning process.  And, as shown by their attitude to flying, the public has very low risk tolerance.  Standards are lower (mere 1000 year floods indeed!) in domains where the connection between procurement decision and disaster is tenuous. Public involvement in the design of nuclear reactors (or flood defences or epidemic and other disaster planning) is minimal.  The effects of mistakes appear only decades later.  The market cannot be relied on to impose discipline.  Government must step in.

2. Independent agencies may regulate particular industries, but a strong central government function is needed – an Office of Risk Assessment and Mitigation, perhaps, or maybe simply Disaster Avoidance.  At present, it seems the UK Chief Scientist takes on this role.  Maybe responsibility for risks could be made more explicit, but science is not be the only discipline required, so perhaps a new department should be established.  I would not envisage a large staff.  The role would be more akin to audit of government departments, functions and divisions of responsibilities.  And brainstorming scenarios.  A similar office may be needed at other levels – large cities on the one hand and the supranational (so the EU and UN) on the other.  Regardless of the details, teeth are needed.

I was shocked that Japanese towns were so vulnerable to the recent tsunami.  After all, this sort of thing has happened many times before – tsunami is a Japanese word.  I was even more shocked the nuclear plants were so exposed to risk.  It may be somehow rational at an individual level to ignore 1000 year risks – after all a given disaster is unlikely to occur in one’s lifetime, or before an executive has enjoyed his healthy pension – but we are now in an era where we are not only more interconnected than ever before, magnifying and proliferating risks, but also have come to expect a lifetime free from war, plague, pestilence and the other ills brought to previous generations by the ancient Horsemen.

On Misplaced Certainty and Misunderstood Uncertainty

I know the climate scientists know they’re right, but a little care is called for. It’s important not to play fast and loose with the figures – especially when criticising someone else for playing fast and loose with the figures!

In a post entitled Getting things right, Realclimate yesterday addressed a piece of rogue science conducted apparently in-house by an NGO. Gavin Schmidt wrote:

The erroneous claim in the study was that the temperature anomaly in 2020 would be 2.4ºC above pre-industrial. This is obviously very different from the IPCC projections… which show trends of about 0.2ºC/decade, and temperatures at 2020 of around 1-1.4ºC above pre-industrial.

But the chance of “temperatures at 2020″ being 1.4ºC above pre-industrial seems to me pretty remote – certainly less than 2.5%, if Gavin is quoting within 2 sigma confidence limits, as is customary.

You’d think in a blog post titled “Getting things right” that it was pretty important to get things right…

So I posted a comment and was pleased to see not one, but two replies:

Now I’m confused. I understand we are currently about 0.8ºC above pre-industrial. A mean global surface temperature 1.4ºC above by 2020 implies a 0.6ºC rise over the next decade.

[Response: The range is just eyeballing the IPCC figure for the year 2020 - so there is some component of internal variability in there as well. - gavin]

[Response: GISS temperature of 2010 (which happens to be right on the long-term trend) is 0.9 ºC above the mean 1880-1920 (and the latter is probably a bit higher than "preindustrial"). -stefan]

OK, let’s take 0.9ºC, though that’s not a figure you often hear.

The IPCC graphic Gavin is referring to when he says “projections” is one I’ve never really liked:

It’s all a bit too imprecise and pretty for my liking. For example, the yellow line (constant GHG levels from 2000) diverges from the other scenarios almost immediately, even though natural variation would initially overwhelm differences between emission trajectories.

It does rather look, though, as if at least one of the scenarios could, according to the models, lead to warming of 1.4ºC above the pre-industrial level. Could this be because emissions in the scenario are much higher than we’re actually experiencing? No, Gavin notes that:

* Current CO2 is 390 ppm
* Growth in CO2 is around 2 ppm/yr, and so by 2020 there will be ~410 ppm
So far so good. The different IPCC scenarios give a range of 412-420 ppm.

The difference between 420ppm and 410ppm would only lead to a 0.1ºC extra rise in temperature over the very long term and even then the climate sensitivity (the eventual temperature increase for every doubling of the atmospheric CO2 level) would have to be on the high side – around 4ºC.

No, the problem is that the temperature hasn’t risen fast enough to 2010 for the more extreme modelling predictions in the IPCC figure for 2020 to be sufficiently likely any more. The IPCC graphic is out of date, plain and simple.

It’s a bit puzzling to be honest why Gavin used the IPCC graphic, because another Realclimate post today has trend-lines suggesting a much more accurate estimate of the likely global mean surface temperature at 2020 – around 0.2ºC higher than at present or around 1.1ºC above the pre-industrial level (as Stefan noted, 2010 is roughly on trend).

But how confident are we in this estimate? What is the range Gavin should have quoted?

Well, here’s the point: you can’t just express uncertainty by running a few models with slightly different starting conditions (the “Monte Carlo” approach) and discarding 2.5% at each extreme of the resulting distribution.

No, we have to actually think about what we’re doing.

It rather seems to me there are different kinds of uncertainty that we might want to consider when trying to predict the temperature “at 2020″.

What are the types of uncertainty we might need to take into account?

Parameter uncertainty
These are our “known unknowns”. In this case, we don’t actually know that the trend is 0.18 or 0.19ºC per decade as discussed at Realclimate. It looks like it is, but this could change when we get a bit more data – maybe we’ll find over a longer timescale that the real figure is 0.16 or 0.21ºC per decade. This makes us less certain about temperatures further out – at 2030 or 2050, say – than at 2020.

But a relatively short time into the future, parameter uncertainty is dominated by:

Calculable statistical uncertainty
Measurements of mean surface temperature show some variability about the underlying trend, as can be seen from the graphs in the Realclimate post discussing the data for 2010.

But the most any year has varied above the trend-line is about 0.2ºC in the case of 1998, which remains one of the 3 warmest years on record (with 2005 and 2010) due to the super El Nino that year. Maybe Gavin is implicitly including the possibility that there will be another strong El Nino in 2020. But that would only get us to a 1.3ºC total temperature increase (1.1ºC for the trend plus 0.2ºC for the El Nino), not 1.4ºC.

Statistical distribution uncertainty
It’s just conceivable Gavin calculated the Standard Deviation (SD) of annual temperature deviations from the trend and found it to be 0.15ºC or more so that 2 SDs includes 1.4ºC, so even if the long-term increase in temperature around 2020 is our 1.1ºC, there may still be a greater than 2.5% chance that the temperature in that one particular year is 1.4ºC or above. The only trouble is, with a mean of 1.1ºC and SD of 0.15ºC there would be an equal probability of 2020 being much colder than usual, so Gavin would have had to give a range of 0.8-1.4ºC.

Ah, but maybe Gavin expects the distribution to be skewed, so that freakishly hot years are more likely than freakishly cold ones…

The point is we don’t actually know a priori what the distribution of probabilities (often called the Probability Density – or sometimes Distribution – Function, or PDF, if that isn’t too confusing!) for the annual mean temperature of a given year actually looks like. We need a theory to tell us that – and the PDF could be complex, not a nice normal, lognormal or power curve at all.

Damn, we already have three sources of uncertainty compounding our estimate of the 2020 temperature!

It can’t get trickier than this can it?

Execution uncertainty
Yes it can.

Global temperatures are depressed following volcanic eruptions. It’s almost as if these are being ignored and that global warming projections include the implicit qualifier: “unless there’s a major volcanic eruption”. These are frequent enough for them to be included in our “2 sigma” (central 95%) range: volcanoes in 1963 (Mount Agung), 1982 (El Chichon) and 1991 (Pinatubo) depressed global temperatures by up to 0.3ºC. Despite a long-term warming trend, the temperature “at 2020″ could easily be knocked back to 2010 levels, that is, 0.9ºC above pre-industrial, or below.

I don’t want anyone coming back and saying I predicted 2020 to be warmer than 2010 and it wasn’t. Sure, I could say “the theory was right, there was just that damn eruption”. But really we need to include the possibility of volcanic activity if we’re going to make a serious forecast.

I’m beginning to think 1-1.4ºC above pre-industrial might not be that good a prediction for 2020. It seems a volcanic eruption could push us further below our central forecast of 1.1ºC than a strong El Nino could lift us above. I suspect 2 sigma confidence limits are more like 0.8-1.3ºC, with the proviso that a really serious volcanic event could leave us even cooler, without the possibility of a corresponding extreme warming event.

The point, of course, is that uncertainty in a complex system, such as the climate or the economy isn’t likely to be a simple mathematical relationship. We need to explore the theory itself. We need qualitative as well as quantitative understanding.

Unknown unknowns
So far our 2020 temperature predictions have assumed we’re certain about our theory.

But maybe we’re not as smart as we think we are.

This is where it gets really difficult. Nevertheless, we should really have a look at any developments that are bubbling up. For example, Realclimate itself has discussed modelling that suggests there could be natural cycles that affect the temperature over timescales of decades. Personally, I think there could be something in this.

Again, the risks, according to the researchers, are to the temperature downside over the next decade. How sure are we that the groups looking at these patterns of variability are wrong? Not more than 95%, surely?

Let’s make one final allowance. Let’s take account of this unknown unknown and predict that the mean global temperature at 2020 will in fact be in the range 0.7-1.3ºC above the pre-industrial level, with a central prediction of a 1.1ºC rise. That is, it will be from 0.2ºC cooler than 2010 to 0.4ºC warmer, with a median expectation in the PDF of a 0.2ºC rise, so a skewed distribution. Think of the 0.2ºC drop as maybe some cyclical cooling cancelling out some of the warming trend plus a bit of volcanic action; the 0.4ºC warming would perhaps arise with a continuation of the current trend plus a big El Nino.

This is the point I want to make: the PDF is in large part a judgement, based on understanding (so there’s plenty of people who could make a better stab at it than me). Number-crunching on its own will never do the job.

I agree with the guys at Realclimate, though: it’s important to get things right!

On Hulme on Science

This post is an addendum to my previous musings on Mike Hulme’s Why We Disagree About Climate Change. In particular I want to respond to Paul Hayne’s comment that:

“Mike Hulme’s argument is not relativist. He is arguing that there really is no argument that can leverage action, which seems pretty true.”

OK, I suppose – after re-reading Chapter 3 of Why We Disagree – my claim did go a bit far. However, I’m not sure I want to concede the point fully.

First, I’m not the only one who’s confused. What was uppermost in my mind I think were the comments about Why We Disagree made by Peter Kircher in Science (pdf), to which Hulme refers on his website, as detailed in my original post.

I concur with Kircher’s view that “Hulme’s book invites misreading” and his disquiet over Hulme’s infamous passage (p.80-2) discussing how science “must concede some ground to other ways of knowing.” There is, though, a way in which this makes sense, which Hulme doesn’t identify and which doesn’t in any way undermine science.

Second, any critique of science must always address the fundamental precept that science is about testing theories against reality. It either describes the world or it doesn’t. There’s no room for compromise with “other ways of knowing”.

There’s one little fly in the ointment, though, which is very apparent in the social sciences. Concepts are not always easy to define. What is “poverty”, for example? Before you can study “poverty” you have to get out there and translate what people mean by “poverty” into something or things that you can actually measure.

Hulme refers to “local tacit knowledge”, which he patronisingly suggests is “not conventionally classified as scientific knowledge”. He muddles strategies for coping with climate conditions with describing “environmental change” and weather-forecasting, but certainly some of what he’s driving at very much is scientific knowledge – climate science relies on interpretations of subjective historic anecdotal evidence in diaries, ships’ logs and so on.

The issue is merely about communication between scientists and those affected. In the case of climate change, science may need to translate its scientific predictions – expressed in terms of directly measurable parameters – into language that relates to people’s day to day experiences. But those experiences are not “other ways of knowing”.

Let’s take the example of “severe winter weather” in the UK, since “here’s one I prepared earlier”! As I explored recently – there is no direct correlation between measurable parameters and the common perception of, in this case, what constitutes a “cold winter”. No-one writes books about, say, February 1986, which was exceptionally cold, whereas (slightly) milder conditions with more snow, such as the Winter of Discontent (1978-9) and perhaps December 2010, linger much longer in the collective memory.

Science could, in principle, develop a “severe winter” index which included temperature extremes, averages, snowfall, lying snow days and so on. Trouble is, different people would want to constitute the index differently. Hence we all have to refer to the same variables if we want to make comparisons. This is what science is. It doesn’t stop us all making our subjective judgements, though.

So, there’s an inescapable conclusion: we have to agree on a framework, on what we can measure in order to make objective comparisons.

And this is the real weakness of Hulme’s work. In terms of both the science and making decisions on emission trajectories, we need a quantitative framework. Or we simply can’t reach any sort of agreement. It’s all very well to note that people have different values, but we can’t conceivably ever agree what is an acceptable level of climate change based on religious and political views. It is irrelevant on one level that the media distort the debate as Hulme goes on to discuss in Chapter 7, The Communication of Risk. This doesn’t alter the consequences of different courses of action and therefore the optimum path by one iota.

It might also be worth noting, en passant, that it is in fact historically somewhat unusual for public opinion to greatly matter in decision-making. The reason the media has influence is a result of our current political system. At most other times in history a ruler, or elite would simply make the decision. The long-term interest of society as a whole was the responsibility of a small group and not something actively contested between different interests. Maybe, as a civilisation, we need ways of making a clearer distinction between the general interest and the individual and sectional interests that drive our political processes. Tricky stuff!

Nevertheless, just as we can only meaningfully discuss and quantify the physical phenomena of climate change within the agreed framework that we call science we can only decide on a course of action in response to global warming by agreeing a framework that permits quantification.

And that framework is called economics.

Musing on “Why We Disagree About Climate Change”

I give in. Over the holiday season I’ve been improving my education by reading Mike Hulme‘s thought-provoking book Why We Disagree About Climate Change: Understanding Controversy, Inaction and Opportunity. Maybe I’m committing a cardinal sin, but I’m going to try to capture my thoughts on Why We Disagree without a clear idea where they’re leading. Perhaps because I haven’t finished reading the book yet!

Whilst I would recommend Why We Disagree as an introduction to a set of issues that are too rarely and superficially discussed, I find myself alarmed at the way the debate is going. The movement that has grown up in response to the global warming threat is more deeply confused than ever. There is a lack of clarity of thought around far too many aspects of the problem of global warming and how to organise a coherent response.

But what’s prompted me to jump the gun was committing another cardinal sin. I idly followed a backlink to this blog. It was automatically generated, but turned out to be very relevant. It led to a post at Haunting the Library, a new GW sceptic blog, which laid into a truly cringeworthy Guardian CiF piece by a Polly Higgins.

Polly Higgins argues for a “law on ecocide“. She particularly wants to prosecute corporations. Presumably she wants to create a world government or at least rewrite the Treaty of Westphalia.

Preamble: Power and the Law

Putting to one side Polly Higgins’ unwise use of comparisons between ecocide and Nazi genocide – I kid you not, read her piece – she misunderstands the role of the law.  The law expresses power relations between society and the individual.  Once the law proscribes (or prescribes) behaviour of some kind, the norm – for example, “don’t sell drugs” – has been agreed.  OK, the legal system is a contested space, but probably best to fight only battles you have a chance of winning.

Enacting a law does more than express a societal norm.  It also criminalises the behaviour it proscribes (or in the case of civil law recognises plaintiffs’ rights to redress).  There are other options than criminalising undesirable behaviour.  Once you have the power to enforce an agreed norm, e.g. if you’re an elected government, you could tinker with incentives.  In the case of drink, for example, rather than try to enforce a law limiting consumption you can raise taxes on alcohol.  When it comes to drinking and driving, though, a strict legally enforceable limit is considered appropriate.

So, what Polly Higgins fails to appreciate – besides the social norm of avoiding casual comparisons with Nazi atrocities – is the need for a coherent two-step plan:

1. Establish the power to prohibit or limit specific behaviour.

2. Identify the appropriate levers to control said behaviour.

A problem with global warming is that it is global in its diverse causes and global in its diverse impacts.  (1) is therefore difficult to achieve.  This might not matter if we either had a world government with the power to deal with the issue or the states that are prepared to project their power, principally the US, were prepared to do so in support of the cause.

But even if (1) were achievable, (2) also needs to be addressed.  Criminalisation might not be the most effective strategy.  The absurd, prohibitionist “war on drugs”, for example, arguably creates more problems than it solves.   In general, I suggest, it’s not a good idea to try to criminalise behaviour in which many people are engaged.

Where the issue gets interesting of course is in the interaction between (1) and (2).

The more power you have the easier it is to criminalise behaviour.  If you happen to be in control of a totalitarian government you can outlaw whatever you like.

On the other hand you need very little power to change incentives.  Simply by buying something you change behaviour throughout the supply chain.  To make a real difference you need to do a bit more than that.  But people are prepared to accept taxes that increase the price of things they may enjoy, but know aren’t good for them, at least in excess.  Hence tobacco and alcohol duty are accepted and are effective to some extent, whereas prohibition would fail, even if the laws required could be passed in the first place.

In the case of carbon emissions, where on the power-spectrum is Polly Higgins, do you think?

Which brings me on to Mike Hulme’s book, Why We Disagree About Climate Change.

Hulme’s project is an important one, and well executed, but, at least as far as Chapter 6, I fear a critical theme has been omitted and that this undermines the whole discussion.

Society and the Individual

Society is not the sum of individual interests.  Let me repeat that in case anyone missed the point.  Society is not the sum of individual interests.

Consider how behaviour is regulated.

Society as a whole attempts to regulate the behaviour of individuals by legal or other means as seen in relation to Polly’s counterproductive proposal to criminalise “ecocide”.

Individuals’ behaviour takes into account sanctions and incentives society as a whole may put in place.

Society has an interest in maintaining itself indefinitely; individuals may or may not be concerned about the future.  Society and individuals are qualitatively different.  Much of the time we pursue our individual interests.  But we expect certain agents to act in the interests of society.

We have collective values.  We expect society to maintain itself even if it doesn’t directly affect us.

Let’s cut to the chase.

Comparing Markets and Values – a Category Error

Chapter 5 of Why We Disagree, The Things We Believe, is primarily about religion but suggests three categories of solutions: correcting markets, establishing justice and transforming society (section 5.4, p.161-9).

But we’re comparing apples and lemons.  Market interventions are a way of achieving agreed objectives within the whole of society, in this case globally.  Establishing justice and transforming society are motivations of individuals or groups for influencing the objectives.

It is alarming not just that Hulme writes:

“These sweeping ideas for commodifying carbon and globalising its market through either free or regulated trade sit uneasily with many of the beliefs expressed in religious and other spiritual traditions”.

but also that he notes WWF UK have:

“…suggested that there are inherent contradictions in ‘attempting to market less consumptive lifestyles using techniques developed for selling products and services.’ “

This is simply incoherent.  Especially to a WWF “Supporter” who yesterday participated in an online WWF “Membership” survey.  If market research isn’t a “technique developed for selling products and services” I don’t know what is.

If we actually want results, I suggest we have to leave it to the technocrats to determine how best to reduce carbon emissions.  All pressure groups can and should do is build support for objectives, such as to reduce carbon emissions, or perhaps more broadly avoid dangerous climate change.

The problem is all pressure groups have their own over-riding objective – to boost their own support.  They need to have a coherent ideology.  They need to sell the illusion that it is their brand that is effective.

Of course, WWF is easy to pick on, in part because they don’t in fact have Members, only Supporters.  They’re not alone in spinning in this particular way, but to my mind, strictly speaking members have – or at least can have – some kind of influence.  This is not the case in WWF.  Policy is not determined by votes of the members, for example.  WWF is selling you something.  And the ratio of brand to product is very high!

If we really want to stop global warming we need to recognise the constraints on coordinated global action.  Market-based solutions of some kind are pretty much the only game in town.

Society, Individuals and Value

Hulme reports in Chapter 4, The Endowment of Value on the discounting of the costs of climate change as used, for example, in the Stern Report.  Every time I read about this I find myself entirely bemused and Hulme, I think, has unintentionally helped me put my finger on the problem.  What am I saying?  Why give Hulme the credit? – I knew this already, I was just hoping Hulme did too.

Stern’s economic analysis – or at least his use of discounting of future costs – looks at the problem from the perspective of individual actors (people or commercial enterprises, say).  We need to consider society as a whole.

The issue is around the discount rate – how much future costs of damage caused by climate change should be reduced by each year when compared with costs in the present.

As Hulme reports (p.126), Stern used two discount rates, a “time discount rate” of 0.1% and a “per capita growth rate” of 1.3% since “we” will be wealthier in the future.

The time discount rate always gets me.  It’s to allow – and this is serious – for the possibility of the human race going extinct before our global warming problems come home to roost.  This is ludicrous.  The logic implies that if we don’t “go extinct” we won’t have invested enough in preventing global warming.  Presumably this is why people don’t save enough for their pensions.  Obviously there may only be a 90% chance of needing the money – you could die or win the lottery.

Imagine if the scenario were just a little different.  Imagine extinction of the human race is certain if CO2 reaches say 500ppm.  We have to spend £10bn now to stop that happening in 100 years.  Ah, but we may be extinct anyway!  So let’s spend just £9bn (that’s £10bn discounted by 0.1% for each of the next 100 years – I know this should be compounded so it’s actually less than £9bn, but that’s not the point.  The point is…).  Damn, we haven’t spent quite enough – CO2 will hit 500ppm and wipe us out.  As I say, this is ludicrous.

OK, so that’s the overall discount rate down from 1.4% to 1.3%.

What about this “per capita growth rate”?  The argument is that it’s not worth spending £1 today to save £1.0129 next year (compounded over time, so it adds up, don’t it), because we’ll be able to create £1.013 worth of goods and services (or capital) next year for the same effort it takes to create £1 this year.

Very persuasive.

Not.

The problem I have with this is that I can’t think of any effect of global warming that won’t rise in proportion with the per capita growth rate.  In fact, it’s very easy to make a case for many costs to rise faster than the per capita growth rate!

Consider the loss of capital assets caused by global warming.  For example, a city may be destroyed due to rising sea-levels or increased storminess or both. The value of that city in the future will be greater than it is today.  Its productive capacity will have increased by as a best estimate – you’ve guessed it – the per capita growth rate.

Or people may be killed due, say, to the effects of a heatwave.  The direct economic loss will be their own individual productive capacity, which will on average have increased from today’s by – you’ve guessed it – the per capita growth rate.

How do we put a value on quality of life?  Well, biodiversity, the preservation of cultural artefacts and ways of living (referred to by Hulme as “natural capital and the aesthetics of living”, p.115) will, at a best guess, be worth as much in the future as a proportion of everything we consume, as they are today.  That is, the costs of damage to the environment will have increased by – you’ve guessed it – the per capita growth rate.

Of course, it’s easy to argue that in the future we will value our own lives, the lives of others and the environment relatively more highly than we do now.  And Hulme even cites Ronald Inglehart who has made the persuasive argument that concern for the environment is a luxury good valued more highly the more wealthy we become.   (Damn, something else I can’t claim to have thought of first!).

I might even add that the only way per capita productivity growth can occur is if we become more interconnected and specialised.  The relative cost of damage to capital and loss of life will therefore be higher in the future.  The more we rely on each other the more costly disruption becomes.

I can see no justification whatsoever for using a discount rate of greater than zero.  Arguably it should be negative.

Stern correctly argued that we should have no pure time preference.  That is, we as individuals may prefer jam today over jam tomorrow (so don’t put enough in our pension funds), but society as a whole transcends time.  We’re all gonners if we do anything other than weigh benefits to me now as at most equal to costs to someone else at some indeterminate time in the future.

Science and Society

Hulme has me really alarmed in his discussion of science (Chapter 3).  We disagree about climate change because we disagree about the science, apparently.  Yes, of course, but society as a whole needs some way of evaluating the risks.

Hulme seems to take a relativist position akin to that of Steve Fuller.  Take this summary from his website:

“In Philip Kitcher’s wide-ranging essay in Science on ‘The Climate Change Debates’ [pdf] I am struck by two things – which are not very new, but which are very important. First, is how the framing and public discourse around climate change differs between countries: as Kitcher puts it, where ‘societies … are inclined to see matters differently’. This is brute fact sociological reality, just as non-negotiable as the radiation physics of a CO2 molecule. Recognising this means that as soon as scientific knowledge enters public discourse – whether this knowledge is robust, imprecise or tentative – different things will happen to it and different social realities will be constructed around it. For me, this is the essence of the climate change phenomenon.

The second, related, thing to emphasise is how predictive claims about the climate future – and its impacts – are inextricably bound up with imaginations (e.g. scenarios) and value judgements (e.g. discount rates) about the future. One could argue that such considerations fall within the legitimate reach of ‘climate science’ and the elite scientific expertise Kitcher claims any genuine democracy needs. But for me it is these extra-scientific dimensions of climate change ‘knowledge’ which motivated me in my book ‘Why We Disagree About Climate Change’ to challenge a narrow appeal to science for engaging our publics around the idea of climate change. It really is not about ‘getting the science right’. It is just as much about engaging our imaginations, about facing up to the ways different peoples and cultures construct meaning for themselves, about the very different values we attach to the future. And because of this I don’t believe Cassandras such as Jim Hansen and Steve Schneider should have the last word.”

I’m baffled how he can refer to James Hansen as a “Cassandra” – Kitcher’s essay suggests only that Hansen and Schneider “play the role of Cassandra”, standing outside the debate rather than within it. I can imagine accusing the scientists of hubris, perhaps, thinking they know more than they do, but crying wolf [which is what I assume Hulme means - otherwise his comment would make no sense at all - since the point about Cassandra is she was right and nobody listened!]?  No.  Hansen certainly calls it as he sees it – everything I’ve ever seen of his has been rooted in what I would describe as fairly mainstream science.  (Though I’ve ordered “Storms” from Amazon anyway – it’s just come out in paperback).

Hulme urges us to face up to “brute-fact sociological reality”, as if this represents some new way of looking at the world, something that – perhaps with one exception – we’re all missing.  Global warming is a physical phenomenon – and by the way, sociological realities are nothing if not negotiable, unlike the  radiation properties of a CO2 molecule – but of course it’s a sociological problem.  The same way as anything from dying to the financial crisis is only a problem if we want it to be.  All “problems” are socially constructed, by definition.  CO2 molecules don’t have problems, only sentient beings do.

Society defines problems and has to construct ways of dealing with them.

The nature of the global warming problem depends on the physical phenomenon.  Sure, we can choose whether to say “oh, that’s interesting” or to define it as a problem.  But we can’t do that unless we understand the physical phenomenon.

So, in agreeing the extent of the problem, we have to use the best socially-constructed mechanisms we have.  All science is is a method of determining the most effective ways of predicting (and therefore controlling) physical phenomena.  Essentially by testing interventions against outcomes.  There’s some logic in there and quite a bit of institutional gubbins, but unless we collectively – and we’re talking about global society here – come up with a better “way of knowing”, it really is a matter of “getting the science right”.

Once we’ve done that we can argue about what to do about it. Or rather, we have to argue in in parallel, since science – like society – never ends.

But we mustn’t muddle up things we can measure – temperature, say, or precipitation, or the ability of particular species to survive – with how we feel about those things or our desires as to the kind of society we’d like to see in the future.

And when we come to try to put into effect what we’ve decided to do, maybe it would be a good idea to use methods that are to some extent predictable, and perhaps those that past experience would suggest are most likely to be successful – which probably won’t include implicating much of the global population in a new heinous crime of “ecocide”.  As I said, we’ll have to give it to the technocrats.  Who will almost certainly use markets to do a lot of the heavy-lifting.

We can afford individuals to be irrational, but society itself has to be rational and objective.

I suspect Hulme is going to go on to tell me in subsequent chapters that society is not rational and objective.  Quelle surprise!

The whole point is that when it comes to existential threats we can’t afford not to be rational and objective.

Maybe global warming isn’t in fact an existential threat.  Maybe we can use it as terrain we can contest with our various views of how we’d like the world to be.

But before we conclude that we can afford to disagree about climate change, it would be a good idea, perhaps, for us to remain rational and objective long enough to determine the nature of the physical phenomenon within somewhat tighter constraints than at present.

At the moment we disagree about climate change because, like naughty children, we think we can get away with doing so.

(to be continued…)

Tantric Biofuel “Science”

The advocacy group, if it’s permissible to use the latest imported American argot to refer to a campaign against a policy programme, Food Not Fuel, have kindly emailed me a link to a Reuters Special Report, reporting that the EU may at last be having doubts about its biofuel policy.

The Special Report is so unnecessarily long-winded that it could in itself make a significant contribution to Europe meeting its renewable energy targets.  Here’s the main substantive point:

“The basic assumption with biofuels is that plants absorb as much carbon dioxide while growing as they release when burned in an engine. If you use them as a fuel, their net impact on the climate is close to zero, except for emissions from farming machinery and fertilizers. [Actually these can be very significant, but that's not the main problem].

But this doesn’t take into account a relatively new concept that scientists drily call ‘indirect land use change’. Put simply, if you take a field planted with grain and switch that crop to something that can be used to make a biofuel, then somebody will go hungry unless the missing grain is grown elsewhere or farming yields are massively improved.

The rush to biofuels means the quantities of land needed are huge. Satisfying the EU’s demand alone will require an additional 4.5 million hectares of land by 2020, according to Reuters calculations based on an average of 15 of the studies for the Commission. That’s an area roughly equal to Denmark.

Burning forests to clear that land — which in theory could be found anywhere around the globe — would pump vast quantities of climate-warming emissions into the atmosphere, enough to cancel out many of the theoretical benefits the biofuels are supposed to bring in the first place. EU sources say an upcoming report will point to a one-off release of around 200 million metric tons of carbon due to land-use change from biofuels, paid back slowly as the fuels do their job over the following centuries. That one-off release is roughly the annual fossil fuel emissions of Germany.”   [My emphasis].

Well, exactamundo.

This is rather as I pointed out as long ago as 2007 when I started calculating carbon emission payback periods for biofuels in my essay Biofuels Are Not the Answer.

Clearly the establishment is rather slow on the uptake.

But it’s not just that the study of this and other supposedly complex scientific questions is tantric.  There’s a more fundamental problem.

Maybe it’s all an elaborate job creation scheme, but it is simply not necessary to produce “116 studies, data files and emails, amounting to thousands of pages” (and that’s just the stuff we know about) and have “a charged [email] discussion between those in the frontline of biofuels research on whether indirect land use change was already taking place before 2007″, as Reuters reports.

Indirect land use change (ILUC), as it’s now being called, is not science in the sense that you can measure it in the complex real world.  I know this may be an alien concept to policy-makers, but ILUC is a logical argument.  If you devote significant amounts of land to the production of biofuels, something has to give.  Either there will be less land available for food production than would otherwise be the case, or we will encroach further on the world’s remaining natural ecosystems and forested land than would otherwise be the case.

Reuters note that:

“…agriculture officials, backed by colleagues in the energy unit, have painted the new science as unrefined. ‘Trying to establish the amount of indirect land use change caused by EU biofuels production is simply ridiculous,’ wrote one, whose name was blacked out in the released documents.”

Obviously the officials, who I assume are biofuel proponents, have a point.  But the science is unrefined, not because it’s primitive, as they perhaps imply, but because it is inappropriate to try to refine it.  ILUC is not something that can easily be measured or predicted.  There’s too much going on.  Land productivity varies with technological change and the vagaries of our increasingly unstable climate.  Many factors affect consumption of agricultural products. These uncertainties must be addressed by the disclaimer “all else remaining equal” – they will happen whether we devote land to biofuel production or not.

At some point we need to listen to the common-sense argument.  Reuters end by reporting that:

“…the likelihood of a policy shift in Brussels has grown. After 20 years in German politics, Guenther Oettinger [Europe's new Energy Commissioner] is the kind of man who loathes controversy and policy dysfunction. Many of the architects of the biofuels policy were replaced in an overhaul in January.

‘We promote only sustainable biofuels and take the phenomenon of indirect land use very seriously,’ he said in a written response to Reuters. ‘This is why we have launched several studies on this. If it is confirmed that indeed that there is a serious problem related to indirect land use, we may adapt our legislation.’ “

Guenther, you can commission as many studies as you want, the scientists are not going to be able to give you a bottom-line number on this one.  Eventually you’re going to have to make the call.

On Climate, and Causes in Complex Systems

Why do so many travellers, such as those marooned by the Eyjafjallalokull ash cloud, invoke a panic response on finding they can’t leave a foreign land? I remember that when I was on a memorable trip to Albania in, if I recollect correctly, 1996, our group was playing leapfrog, as it were, with another minibus full of tourists, along a road to the coast. When we stopped – often – for a passenger to relieve the symptoms of one or other of the local stomach-bugs, the other bus passed us, only for us to see them stopped by the roadside a few minutes later. Eventually we pulled up beside them to chat. It turned out that Albania’s borders were shut, in the hope of trapping whoever had blown up the Tirana police-chief. The other group were cutting their trip short. So illogical. We simply carried on with our holiday. [I drafted this a few days ago, but, since then, I've heard, Radio 4's Today programme is discussing the psychology - and even genetics - of the have-to-get-home phenomenon, right now!].

It beats me why so many people spent thousands of euros hiring cars to drive across Europe. Surely staying until the ash alert blew over would have been both cheaper and less stressful.

Whatever they did, though, even those who have spent the last week hitch-hiking from Athens to Calais abroad cannot fail to have heard that, apparently, global warming will lead to more volcanic eruptions.

Is this something we should worry about?

In short, no.

Volcanoes and ice ages

The scare seems to be based on a study of the end of the last ice age:

“Huybers and Langmuir spliced two databases of volcanic eruptions worldwide over the last 40,000 years.

Eruption levels stayed low until around 12,000 years ago, then suddenly they suddenly shot up. The melting ice released so much pressure that the newly liberated volcanoes erupted at up to six times their normal rate, the researchers estimated.

The inferno lasted for 5,000 years and could have pumped enough CO2 into the atmosphere to raise concentrations between 40 and 50 parts per million, the researchers estimate. Changes in ocean chemistry probably released the rest.”

I love the eruption levels “suddenly” shooting up “suddenly”!

Now, a couple of kilometres of ice over a volcano is one thing. It’s reasonable to suppose that would prevent the pressure in a magma chamber that would otherwise have caused an eruption from doing so.

But melting a kilometre or so of ice takes quite some time. And besides, since the last ice age, there aren’t so many ice-sheets left. Worst case, in a few centuries, perhaps, we could feel the effects of some pent-up volcanic activity.

In the meantime, the worst that could happen is that some eruptions are brought forward by a few years.

The hype around the volcano scare exploits our innate difficulty in conceiving long periods of time. It also resonates with research a while back which noted more eruptions at certain times of year. The suggestion was that particular weather conditions – changes in pressure – around volcanoes, could set them off.

This triggering is an entirely different kettle of fish.

Volcanoes and the weather or short-term climate change

Consider a simple model of volcanic eruptions as the sudden release of something we might call “pressure” that builds up over time. Let’s suppose that the main cause of the build-up of “pressure” is geological. Let’s also assume that the weather can cause seasonal variations in pressure. In this model, eruptions will occur when the total pressure crosses some threshold, as in the following diagram:

Because I’m lazy, and Powerpoint is a step back from pen and paper (and reverting to that and scanning is a hassle right now), I’ve shown the total pressure (dotted line) as the sum of the geological pressure and seasonal variations for the first eruption only, but hopefully you get the idea.

It’s not very usual for volcanoes to erupt every 3-5 years, of course – 50 years or so might be more usual – and in real life every eruption is different.

Hopefully, though, it’s fairly easy to see that eruptions are much more likely in this system during the period when the seasonal effect tends to increase pressure. Over this period the total pressure (dotted line) increases much faster than when the seasonal effect is to decrease pressure.

In fact – and hold this thought – if the rate of increase in pressure due to short-term variability is faster than the long slow build-up of pressure, then eruptions, according to this simple model, will always occur during the short-term upswing in pressure.

My proposition is that it is very easy to exaggerate the effect of the seasonal cycle as a “cause” of eruptions. It is merely a trigger.

You can also see that, if, say, the seasonal pressure changes – a gradual trend on top of the annual fluctuations, perhaps, or an increase in amplitude of the cycle – it will not have a large effect on the frequency of eruptions over a long period. The periodicity of the system will still be driven by geological processes. The weather is a secondary driver in this system.

Now, if you didn’t know that volcanic eruptions are caused by a build-up of “pressure” underground, you might hypothesise that they’re caused by weather conditions. You might collect a lot of data and calculate correlation coefficients to “prove” your theory. You might even argue convincingly that, because we know what causes the weather, the weather must cause volcanic eruptions rather than vice versa and furthermore, it is not the case that both the weather and volcanic eruptions are caused by a third factor.

But you’d be wrong.

Could this mistake happen in other circumstances, though?

Solar cycles and the AMO

That old chestnut, solar cycles, surfaced yet again in New scientist a week or two ago. The claim is that there’s a “compelling link between solar activity and winter temperatures in northern Europe.”

Well, maybe there is.

But anyone who’s stayed awake this far will realise that it’s not enough to determine a correlation between solar cycles and weather patterns. Maybe the solar cycle does trigger a change from one state of the AMO (Atlantic Multidecadal Oscillation) to another. But that doesn’t make it the sole or even the main cause of the variability.

To recap, I first explored the idea of the AMO when I became concerned that the emphasis being put on shrinking Arctic ice as an indicator of global warming (GW) could backfire if the shrinkage reverses. My first post on the topic was therefore titled: Spin Snow, Not Sea Ice, the AMO Is Real!. Back then, I noted that the AMO cycle – likely to be variable in length, especially now we have the extra GW complication – tends to be of the order of 60 years or so, with the previous cooling phase lasting from the 1940s to the 1970s. Maybe we’re entering another one.

That first post suggested a mechanism for the AMO, which I discussed a little more in my second post on the topic, Why the AMO Overshoots. So I won’t repeat myself today.

Later, in 1740 And All That I looked at a historical example of a sudden switch from mild to cold winters in NW Europe. The weather pattern that leads to cold winters might be termed an “anti-monsoon”, as I first discussed back in January in Snow Madness and the North-West European Anti-Monsoon.

Two other posts Ice Pie and Ice Sickle explore aspects of the AMO.

The basic argument in all these posts is that the natural cycle – the AMO – is characterised by a set of feedbacks. Positive feedbacks – perhaps including the effect of lying snow, as considered in That Snow Calculation – produce distinct warming (Arctic ice melt) and cooling (Arctic ice recovery) phases. Negative feedbacks cause one phase to flip to the other. But the exact timing of the tipping-point may be caused by external triggers.

My proposition is that by the end of warming phase of the AMO, the seas (especially the Arctic and the North Atlantic) are relatively warm compared to the land. Any sudden cooling event could trigger a flip to the cooling phase, because the land cools quicker than the ocean, so would become relatively even colder.

Possible sudden cooling events are volcanic eruptions or the change to a cooling phase of the solar cycle, as discussed previously for the case of 1740.

A critical point is that the sunspot cycle is much shorter than the AMO (see AMO discussion and graphs in my first post on the subject):

NASA graph of yearly sunspot numbers

The sunspot cycle indicates the total irradiance from the sun, and the rate of variation is comparable to that of other causes such as GW:

IPCC Fig 2.16 recent changes in solar irradiance

Further Implications

Not too many scientists claim volcanic eruptions are “caused”, as opposed to triggered, by variation in the weather or by climate change. Most understand that only over the sort of long timescale that is needed to melt an ice-sheet would the frequency of eruptions change.

But far more common is the explanation of apparent climate cycles – such as the AMO – by variations in solar output. In cases such as this, it is necessary to do more than just prove a correlation. The causal mechanism needs to be clear and must be shown to be quantitatively sufficient to explain the observed phenomena.

Considerable care is required whenever attempting to explain the “causes” of complex system behaviour.

The need to distinguish between triggers and underlying causes of cyclic behaviour also applies elsewhere in the climate system. Furthermore, the distinction between triggers and underlying causes may become blurred – both may be of similar magnitude, creating a resonant system. In particular, over longer timescales than so far discussed, the Milankovitch cycles are not enough alone to explain the ice age cycle. Perhaps they resonate with another cycle internal to the climate system.

In other domains too, it is not possible to assume that the “cause” in a complex system is just that which is evident on the surface. The lax lending practices and cheap money that are held to have caused the credit crisis may just be one part of a deeper, more complex cycle of optimism, deregulation, increased trade and globalisation on one hand and retrenchment and nationalism on the other.

Ice Sickle

I continue to fret about the emphasis on the Arctic sea-ice extent as an indicator of global warming (GW).

I have to chop down (got to justify my blog entry title somehow!) a Guardian story, “Arctic sea ice still low despite winter recovery” (p.20 in today’s print edition), the online version titled incoherently “Arctic winter ice recovers slightly despite record year low, scientists say” and cryptically subtitled “Figures from the National Snow and Ice Data Centre [the NSIDC] indicate six or seven-year low over past three decades”. (They mean 2010 has had the 6th or 7th lowest maximum ice extent – which occurs in March – on record, i.e. of the last 32 years).

The story itself is garbled as well:

“Last night [NSIDC] released the data for the winter of 2009-10 showing the maximum extent reached on 31 March was 5.89m square miles (15.25m sq km). This was 250,000 square miles (650,000 sq km) below the 1979 to 2000 average for March…”

What the NSIDC actually said was that the average for March (15.10m km2 or 5.83m square miles – btw, wouldn’t it be simpler if we all standardised on km2?) was 250,000 square miles below the 1979-2000 March average. In fact, NSIDC’s news posting was titled “Cold snap causes late-season growth spurt” and noted that the maximum sea-ice extent occurred later than usual at the end of March, when the ice extent was only marginally below the 1979-2000 average for that date, as can be seen in the graph illustrating this BBC story about the launch of a satellite to monitor the situation.

I would have thought the real story was the recovery in the maximum Arctic sea ice extent compared to the last few years. “Arctic sea ice still low” is arguably a little misleading.

It is really not helpful to keep spinning Arctic sea ice shrinkage as an indicator of GW. There will be a vicious backlash should nature conspire to undermine the Arctic ice melt narrative. It will then become even more difficult to muster the political will to deal with GW.

The Guardian story goes on to note that:

“Last month, Japanese scientists reported in the journal Geophysical Research Letters that winds rather than climate change had been responsible for around one-third of the steep downward trend in sea ice extent in the region since 1979. The study did not question global warming is also melting ice in the Arctic, but it could raise doubts about high-profile claims that the region has passed a climate “tipping point” that could see ice loss sharply accelerate in coming years.”

Maybe this is what the researchers did actually say – I may have to go the library to check – but, as I pointed out before, it makes no sense to try to distinguish “winds” from “climate change”. Winds are not caused by some arbitrary external force, they are determined by differences in temperature, albedo (reflectivity), moisture content and so on between different areas of the planet. Winds are part of the climate system that is changing, so it is simply meaningless to separate the cause of ice melt into “winds” and “climate change”.

Solving the GW problem is difficult enough without the constant drip-feed of confusing reporting of the issue.