Imagine yourself, for a moment, adrift in a storm-tossed wooden lifeboat. Yours is the only vessel in sight – the only refuge in the heaving sea stretching to the horizon all around you. With a sinking heart – rightly concerned by the potential consequences – you realise the water level in the bottom of the boat is rising. You have nowhere else to go.
Now, the environment in which you find yourself may well be the source of this water – the persistent rain, the sea spray washing over the sides, perhaps even marine bivalve Teredo navalis – shipworms, as they were known in the days of grand wooden ships plying the seven seas – chewing their way through the hull of your fragile boat. That doesn’t mean that the signal fire you lit in the stern might not also be causing a leak. It’s not like you have a leakage budget to work within – “it’s okay, I’m going to take on a gallon of water an hour, so I can shave some more wood out of the sides and stoke the fire, and the rain will ease up to compensate”. Aware that fire is known to consume wood, and that, as my boat is made of wood, I could reasonably infer that my cheery blaze might be a factor – and one over which I had control, the prudent thing to do until I was pretty darned sure of things would be to douse it.
Of course, despite my obvious and melodramatic allegory here, we’re not really talking about drifting lifeboats. Rather, in a summer in which the Australian Bureau of Meteorology has found it necessary to add new colours to the temperature scale on their national synoptic charts, changing climate is probably a fair topic for engaged conversation.
Although I’m a professional scientist, and try to keep myself pretty well informed, I’m under no illusion that I can offer a fair and valid critique of understanding in this area. If that’s what you’re after, I heartily suggest you check out the US Global Change Research Program (www.global change.gov). Me? I’ll put my hand up right now and tell you I don’t fully understand the physics of greenhouse warming, the consequences of changing landscape albedo to a solar energy budget, the details of orbital precession, or the design and function of supercomputer models of climate sensitivity. Unlike a number of (usually self nominated) commentators on climate science though, my philosophy in these circumstances is not to go ahead and shoot my mouth off anyway – at least not without a few glasses of good wine inside me – so this is not principally an essay about the rights and wrongs of understanding on anthropogenic climate change.
Instead I want to talk about the (to me, anyway) curious fact that vested interests and enthusiastic amateurs from all walks of life – politicians, newspaper columnists, school teachers, Jeremy Clarkson – seem possessed of an unshakeable belief that their understanding of climate change and its causes should be given equal weight to, say, Roger Revelle, or the IPCC.
I’m not talking here about debate over how we, individually and as a society, should respond to climate change – what steps we should take, how the cost should be borne. Here opinion and debate clearly should be entertained as we move towards a social contract. But the facts of the matter, the understanding of physical phenomena, does not submit to willpower or popularity. You don’t get to vote by SMS on whether anthropogenic carbon dioxide emissions are a driver of dangerous levels of climatic warming or just a combination of snuggly global duvet and healthy plant food.
By way of analogy to the problem here – diesel has a greater energy content than unleaded petrol. I know that’s true because I read it on the internet. Logically then, if I start putting diesel into my car, it will be more powerful and go further on a tank. Right?
The fact that I used the word logically probably tells you everything you need to know about why it’s important that I listen to my mechanic rather than trying to fix my car myself.
Let’s pursue that metaphor a little farther. Think about it – if this was your car we were talking about (and I might venture here that the climatic system of our entire planet might be a bit more important than that – even if you do wash yours more often than I manage and rotate the tires every 6 months) I doubt you’d be up for self diagnosis – or even taking the advice of Alan Jones – when your engine started knocking. No. I suspect that, like me, you would far rather trust the judgement and experience of auto mechanics who have trained for years and devoted themselves professionally to the diagnosis and correction of engine problems. Even if you did roll up to the workshop door with a worrying knot in your stomach over what they might find under the hood, and just how eye-wateringly expensive it might be to fix.
Yes, some mechanics are better than others, and there may even be shonky ones out there that don’t know what they’re doing, or worse, who are criminally intent on defrauding you by exaggerating or inventing problems. If you do your research though, and find out who other mechanics respect and what they think of each other’s work, I’m pretty confident you could probably do a good job of picking the right person to deal with any engine trouble you might have.
The problem, in its essence, is that ‘opinion’ is a complex and chimeric beast. It covers a spectrum from tastes or preferences, through views on issues of common concern – the ethical and political questions of the day, to views grounded in technical expertise – and here I’d include legal or scientific opinions. The common thread is that all these areas admit a degree of subjectivity and uncertainty – but not all are equal.
You can’t really argue about the first kind of opinion. It would be ludicrous for me to tell you that you were wrong to prefer sticky date pudding to cheesecake. Where this issue starts to go off the rails though is that we sometimes take opinions of the ethical and even the expertise-based sort to be unarguable in the same way such questions of taste are.
The silly – even embarrassing – thing here, at least for somebody coming from a Western philosophical tradition, is that Plato pretty much had this distinction sewn up 2400 years ago.
Today though all too often – whether by design or, I suspect usually more likely, ignorance, we seem to have forgotten this lesson.
Bob Brown, former leader of the Australian Greens and Federal Senator, argued long and vociferously against nuclear power throughout his career, despite not being a nuclear physicist. All well and good – but Meryl Dorey – leader of the Australian Vaccination Network (don’t be fooled by the name – this is a group vehemently opposed to childhood vaccination in all its forms) has used Brown’s record to argue that she should, in a similar vein, be listened to in regards to the healthcare of our children, despite having no medical qualifications of any stripe. The crucial difference between the two is that Dr Brown never represented himself as an authority on the physics of nuclear fission. He was always, entirely appropriately, commenting on policy responses to science, not the underlying scientific understanding. Dorey, in contrast, essentially tries to represent that her views should factor in debate regarding the biomechanics of vaccination and immune response itself – that her personal biases should be weighted equally to expert and scientifically validated opinion.
So – back to climate change – let’s take on board Plato’s distinction for a minute and ignore the opinions of the Nick Minchins and Lord Moncktons of the world. What do professional climate scientists – those experts who have devoted themselves to understanding the detailed interactions of climatic systems and earned the respect of their critical peers – understand to be happening to our climate?
First and foremost, our planet is warming up. Using any of a wide range of indicators (ocean heat content, sea surface temperatures, sea level, temperatures in the lower and middle troposphere, the rates at which glaciers and ice sheets are melting), the overall temperature of the Earth and the corresponding energy in our climate system are increasing.
According to a study recently published by a team of scientists from the Potsdam Institute for Climate Impact Research, there are now on average five times as many months with record-breaking high temperatures at measured locations worldwide than could be expected without significant and ongoing warming occurring. In parts of Europe, Africa and southern Asia, the figures are even worse – with instances of record-setting monthly temperatures exceeding statistical expectation by a factor of ten.
While there are a number of influences on the climate system, such as changing levels of solar radiation and abundance of atmospheric aerosols, independent climate researchers also almost universally conclude that this warming has been produced dominantly by increased levels of carbon dioxide in the atmosphere, with a significant proportion of this emitted by human activities.
Now remember, that’s not me saying this – these are the expert opinions of the big beasts at the climate science waterhole with the expertise and experience to give their opinions real weight. These are the people we should be listening to.
In a recent essay on Science Communication (‘Three Monkeys, Ten Minutes: Scientists and the Importance of Communication Skills’ – WordPress, 18 October, 2012), I used the metaphor of taking sides in a scientific debate you don’t understand being like weighing in to an argument in a language you don’t speak – a Frenchman and a German speaking in Spanish, let’s say – on the basis of liking one participant’s accent more than the other. In the field of climate change, the position of someone who would deny the reality of anthropogenic warming is even more tenuous, because as the debate stands its like 97% of the Spanish speakers in the room (everyone except Pierre’s mother and the crazy old guy whose brother was killed in the second world war and hates all Germans with an unquenchable rage, let’s say) agree that our French friend is wrong-headed and it’s Heidi we should listen to – but still there are non-linguists willing to back up the Frenchman with an unthinking “yeah, what he said” against all comers.
To come full circle to our fragile boat alone on the stormy seas – although the consequences of putting out my fire if it wasn’t reducing my vessel’s seaworthiness might be unpleasant (I’d be wet and cold – and frightened, alone in the vast empty expanse of the ocean), the consequences of not taking action if my hypothesis ultimately proved correct would be much, much worse.
More importantly, although I would really like to know exactly where the water was coming from and which source was the most important (sorry, scientific curiosity has me in its thrall), my first reaction wouldn’t be to set up an interim enquiry and design some experiments. No. Me? I’d start bailing.