Climate Change Chaos: the long and the short of it

The aspect of climate change science that lends itself most readily to demagoguery is when it predicts the future. Unfortunately, climate science would not be much use to us if it didn’t.

Those who take the science seriously exist in an uncomfortable place somewhere between curiosity and dread. We want to know, want reassurance that our fears are rational, and that the costs of mitigation and adaptation are justified. Climate scientists inevitably find themselves obliged by their employers, by the media, by governments and the public they are supposed to serve, to make predictions.

Just like doctors; imagine how you would feel if your doctor said you were dying, but when asked how long you had, said ‘oh, I don’t know…could be weeks, could be years’. Not much help, really.

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The ‘polar vortex’ gives rise to the latest bit of short-term demagoguery, along with contrarians and their smug taunts when a research ship got trapped in the Antarctic ice. In some ways this is all too predictable; climate denial must constantly resort to this kind of spin, mainly to cover up the embarrassing lack of science, and credible scientists, that support their opinions.

We can’t do much about the contrarian crusaders stuck in their trenches, since they appear to be digging ever deeper defences against reality. We should spare a thought for the public, however; it is hard to accept the concept of ‘global warming’ when you’re freezing. For so many of us, engaged in the fight between intellectual understanding of warming and the immediacy of several feet of snow, it’s understandable how many rounds will be won by frost-bitten fingers.

One of the key communication failures in climate science is that we don’t distinguish forcefully between predictable, ‘linear’ responses to global warming – often expressed as generalisations – and the short term chaos that climate change engineers. In the long term, statements like ‘the planet is warming’ will be validated both by data and experience. The same is true of claims like ‘wet places will get wetter, dry places dryer’ – a prediction made by numerous diverse authorities on the subject. (Scientists prefer to call them ‘projections’, and this isn’t a hair-splitting distinction. What the future holds is calculated by extrapolation, not guesswork).

Trouble is, for the public such vague projections suggest something that seems very obvious; steady changes year on year – incremental change consistent with what the scientists are saying. Next year will be hotter/wetter than last year. Every year there will be less ice. And yet, as even the demagogues know, short-term climate (a.k.a ‘weather’) is not that simple, and certainly not that predictable.

The most compelling example of this problem is the alleged ‘hiatus’ in surface temperatures. Various investigations are under way to determine why things are changing in such unpredictable ways. While there are plenty of theories, we don’t yet understand why the oceans started taking up more heat in recent decades, any more than we understand why Northern Hemisphere seasonal temperatures are fluctuating so wildly year on year, region by region. (At the same time Americans are fitting snow chains in Texas, Scandinavian bears are waking up from hibernation early because it’s so unseasonably warm, and UK gardens are graced with Snowbells in December).

Another example is the very sudden loss of Arctic ice in 2012, which few predicted. In fact, science doesn’t seem any better equipped to predict short-term manifestations of climate change than the average taxi driver, so capricious are the phenomena. Perhaps it’s about time we started saying so in much less equivocal (and defensive) terms.

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It isn’t just weather that is unpredictable in the short term. Climate change cannot be properly observed until we have enough data over time to distinguish noise from signal, weather from trends. But climate science makes a rod for its own back when it talks about change without clarifying the chaotic nature of short term responses compared to the analysis of long-term trends.

For some time, it has seemed prudent to discuss climate change not as warming, not as predictable wetness and dryness, not as hot and cold, not as gradual changes from one state to another. Instead, climate change can be described – quite accurately – as destabilisation of the climate. We can make it clear that in the long term, the planet will work out a new set of predictable patterns for climate, a new equilibrium, but right now – and possibly for some centuries to come – the climate will be unhinged, a mad thing heaving and blowing this way and that.

Every stable pattern we are used to, and depend on (agriculture being the prime example), could be undone. As more and more energy builds up in the climate system, so that energy will make itself felt. We can’t say how it will manifest itself, but since climate is a system of energy imbalances, it’s hardly counter-intuitive to insist that more energy will magnify the effects.

Consequently, our expectations at every turn are likely to be confounded – including our scientific expectations of how climate change will manifest itself in the short term. We should also be clear that the inability to predict short term responses isn’t a failure of science, but the conflict between our desire to know the future, and nature’s resolute refusal to reveal its short-term plans on demand, as any weatherman can tell you.

We should put much more emphasis on the chaotic responses we can expect on annual or even decadal scales. This will be hard for scientists. I suspect they feel an obligation to make their fragile predictions (the most egregious of which are when people put dates on the emergence of phenomena), because to admit they can’t predict short term responses can be spun as professional failure. The demagogues would make much unseasonable hay out of that: you can almost hear the question ringing out in Parliament or the US Congress; ‘if they can’t tell us what’s going to happen, what the hell are we paying these guys for?’. There will always be demagoguery, but if climate scientists were more candid, perhaps the public might get a better grasp of why climate projections are such a nuanced, complex, unpredictable business.

Returning to my doctor and climate scientist analogy, they have something else in common in respect to reading the future; they can both be wrong in the short term, yet proved right later. A doctor can give you an early date for your demise that, ten years on, you’re still making fun of, but you are still going to die. In a similar way, climate scientists can tell us the planet is going to warm up even as a polar vortex is sticking your fingers to the thermometer. Just as the doctor will be proved right in the end, so too will climate science. The difference is this: we can’t do anything about our mortality, but we can stop destabilising the climate.