There are many who like to reminisce about how much better the summer weather was back in their school holidays. The rose-tinted memories of childhood can seem idyllic, although I also recall summer days of non-stop rain (I did grow up in the UK, after all). Therefore our personal experiences, particularly during our formative years, can promote an emotion-based response that is so far ingrained we fail to consider they may be inaccurate. Subjectivity and wishful thinking are key to the human experience: how often do we remember the few hits and not the far more misses? As science is practiced by humans it is subject to the same lack of objectivity as anything else; only its built-in error-checking can steer practitioners onto a more rational course than in other disciplines.
What got me to ponder the above was that on meeting someone a few months' ago for the first time, almost his opening sentence was a claim that global warming isn't occurring and that instead we are on the verge of an ice age. I didn't have time for a discussion on the subject, so I filed that one for reply at a later date. Now seems like a good time to ponder what it is that leads people to make such assertions that are seemingly contrary to the evidence.
I admit to being biased on this particular issue, having last year undertaken research for a post on whether agriculture has postponed the next glaciation (note that this woolly - but not mammoth, ho-ho - terminology is one of my bugbears: we are already in an ice age, but currently in an interglacial stage). Satellite imagery taken over the past few decades shows clear evidence of large-scale reductions in global ice sheets. For example, the northern polar ice cap has been reduced by a third since 1980, with what remains only half its previous thickness. Even so, are three decades a long enough period to make accurate predictions? Isn't using a scale that can be sympathetic with the human lifespan just as bad as relying on personal experience?
The UK's Met Office has confirmed that 2018 was that nation's hottest summer since records began - which in this instance, only goes back as far back as 1910. In contrast, climate change sceptics use a slight growth in Antarctic sea ice (contrary to its steadily decreasing continental icesheet) as evidence of climate equilibrium. Now I would argue that this growth is just a local drop in the global ocean, but I wonder if my ice age enthusiast cherry-picked this data to formulate his ideas? Even so, does he believe that all the photographs and videos of glaciers, etc. have been faked by the twenty or so nations who have undertaken Earth observation space missions? I will find out at some point!
If we try to be as objective as possible, how can we confirm with complete certainty the difference between long term climate change and local, short term variability? In particular, where do you draw the line between the two? If we look at temporary but drastic variations over large areas during the past thousand years, there is a range of time scales to explore. The 15th to 18th centuries, predominantly the periods 1460-1550 and 1645-1715, contained climate variations now known as mini ice ages, although these may have been fairly restricted in geographic extent. Some briefer but severe, wide-scale swings can be traced to single events, such as the four years of cold summers following the Tambora eruption of 1815.
Given such variability over the past millennium, in itself a tiny fragment of geological time, how much certainty surrounds the current changes? The public have come to expect yes or no answers delivered with aplomb, yet some areas of science such as climate studies involve chaos mathematics, thus generating results based on levels of probability. What the public might consider vacillation, researchers consider the ultimate expression of scientific good practice. Could this lack of black-and-white certainty be why some media channels insist on providing a 'counterbalancing' viewpoint from non-expert sources, as ludicrous as this seems?
In-depth thinking about a subject relies upon compartmentalisation and reductionism. Otherwise, we would forever be bogged down in the details and never be able to form an overall picture. But this quantising of reality is not necessarily a good thing if it generates a false impression regarding cause and effect. By suffering from what Richard Dawkins calls the “tyranny of the discontinuous mind” we are prone to creating boundaries that just don't exist. In which case, could a line ever be found between short term local variation and global climate change? Having said that, I doubt many climate scientists would use this as an excuse to switch to weather forecasting instead. Oh dear: this is beginning to look like a 'does not compute' error!
In a sense of course we are exceptionally lucky to have developed science at all. We rely on language to define our ideas, so need a certain level of linguistic sophistication to achieve this focus; tribal cultures whose numbers consist of imprecise values beyond two are unlikely to achieve much headway in, for example, classifying the periodic table.
Unfortunately, our current obsession with generating information of every quality imaginable and then loading it to all available channels for the widest possible audience inevitably leads to a tooth-and-claw form of meme selection. The upshot of this bombardment of noise and trivia is to require an enormous amount of time just filtering it. The knock-on effect being that minimal time is left for identifying the most useful or accurate content rather than simply the most disseminated.
Extremist politicians have long been adept at exploiting this weakness to expound polarising phraseology that initially sounds good but lacks depth; they achieve cut-through with the simplest and loudest of arguments, fulfilling the desire most people have to fit into a rigid social hierarchy - as seen in many other primate species. The problem is that in a similar vein to centrist politicians who can see both sides of an argument but whose rational approach negates emotive rhetoric, scientists are often stuck with the unappealing options of either taking a stand when the outcome is not totally clear, or facing accusations of evasion. There is current trend, particularly espoused by politicians, to disparage experts, but discovering how the universe works doesn't guarantee hard-and-fast answers supplied exactly when required and which provide comfort blankets in a harsh world.
Where then does this leave critical thinking, let alone science? Another quote from Richard Dawkins is that "rigorous common sense is by no means obvious to much of the world". This pessimistic view of the human race is supported by many a news article but somewhat negated by the immense popularity of star science communicators, at least in a number of countries.
Both the methods and results of science need to find a space amongst the humorous kitten videos, conspiracy theorists and those who yearn for humanity to be the pinnacle and purpose of creation. If we can comprehend that our primary mode of thinking includes a subconscious baggage train of hopes, fears and distorted memories, we stand a better chance of seeing the world for how it really is and not how we wish it to be. Whether enough of us can dissipate that fog remains to be seen. Meanwhile, the ice keeps melting and the temperature rising, regardless of what you might hear...
