Monday, 8 May 2017

Weather with you: meteorology and the public perception of climate change

If there's one thing that appears to unite New Zealanders with the British it is the love of discussing the weather. This year has been no exception, with New Zealand's pre-summer forecasts - predicting average temperatures and rainfall - proving wildly inaccurate. La Niña has been blamed for what Wellingtonians have deemed a 'bummer summer', January having provided the capital with its fewest 'beach days' of any summer in the last thirty years. Sunshine hours, temperature, rainfall and wind speed data from the MetService support this as a nationwide trend; even New Zealand flora and fauna have been affected with late blossoming and reduced breeding respectively.

However, people tend to have short memories and often recall childhood weather as somehow superior to that of later life. Our rose-tinted spectacles make us remember long, hot summer school holidays and epic snowball fights in winter, but is this a case of remembering the hits and forgetting the misses (meteorologically speaking)? After all, there are few things more boring than a comment that the weather is the same as the previous ten comments and surely our memories of exciting outdoor ventures are more prominent than being forced to stay indoors due to inclement conditions?

Therefore could our fascination with weather but dubious understanding - or even denial - of climate change be due to us requiring personal or even emotional involvement in a meteorological event? Most of us have had the luck not to experience extreme weather (or 'weather bombs' as the media now term them), so unless you have been at the receiving end of hurricanes or flash floods the weather is simply another aspect of our lives, discussed in everyday terms and rarely examined in detail.

Since we feel affected by weather events that directly impact us (down to the level of 'it rained nearly every day on holiday but the locals said it had been dry for two months prior') we have a far greater emotional response to weather than we do to climate. The latter appears amorphous and almost mythical by comparison. Is this one of the reasons that climate change sceptics achieve such success when their arguments are so unsupported?

Now that we are bombarded with countless pieces of trivia, distracting us from serious analysis in favour of short snippets of multimedia edutainment, how can we understand climate change and its relationship to weather? The standard explanation is that weather is short term (covering hours, days or at most weeks) whilst climate compares annual or seasonal variations over far longer timeframes. Neil deGrasse Tyson in Cosmos:A Spacetime Odyssey made the great analogy that weather is like the zigzag path of a dog on a leash whereas its owner walks in a straight line from A to B. So far so good, but there's not even a widespread designation for the duration that counts as valid for assessing climate variability.

As such this leads us to statistics. Everyone thinks they understand the word 'average' but averages can represent the mean, median or mode. Since the period start and end date can be varied, as can the scaling on infographics (a logarithmic axis, for example), these methods allow a single set of statistics to be presented in a wide variety of ways.

The laws of probability rear their much-misinterpreted head too. The likelihood of variation may change wildly, depending on the length of the timeframe: compare a five-year block to that of a century and you can see that climate statistics is a tricky business; what is highly improbable in the former period may be inevitable over the latter. As long as you are allowed to choose the timeframe, you can skew the data to support a favoured hypothesis. So much then for objective data!

By comparison, if someone is the recipient of a worse than expected summer, as per New Zealand in 2017, then that personal experience may well be taken as more important than all the charts of long-term climate trends. It might just be the blink of an eye in geological terms, but being there takes precedence over far less emotive science and mathematics.

Perhaps then we subconsciously define weather as something that we feel we experience whilst climate is a more abstract notion, perhaps a series of weather events codified in some sort of order? How else can climate change deniers, when faced with photographs proving glacial or polar cap shrinkage, offer alternative explanations to global warming?

This is where politics comes into the mix. Whereas weather has little obvious involvement with politics, climate has become heavily politicised in the past thirty years, with party lines in some nations (mentioning no names) clearly divided. Although some of the naysayers have begun to admit global warming appears to be happening - or at least that the polar caps and glaciers are melting - they stick to such notions that (a) it will be too slow to affect humans - after all, there have been far greater swings in temperature in both directions in previous epochs - and (b) it has natural causes. The latter implies there is little we can do to mitigate it (solar output may be involved, not just Earth-related causes) and so let's stick our head in the sand and do some ostrich impressions.

As an aside, I've just finished reading a 1988 book called Prehistoric New Zealand. Its three authors are a palaeontologist (Graeme Stevens), an archaeologist (Beverley McCulloch)  and an environmental researcher (Matt McGlone) so the content covers a wide range of topics, including the nation's geology, climate, wildlife and human impact. Interestingly, the book states if anything the climate appears to be cooling and the Earth is probably heading for the next glaciation!

Unfortunately no data is supplied to support this, but Matt McGlone has since confirmed that there is a wealth of data supporting the opposite conclusion. In 2008 the conservative American Heartland Institute published a list of 500 scientists it claimed supported the notion that current climate change has solely natural causes. McGlone was one of many scientists who asked for his name to be removed from this list, stating both his work and opinions were not in agreement with this idea.

So are there any solutions or is it simply the case that we believe what we personally experience but have a hard time coming to terms with less direct, wider-scale events? Surely there are enough talented science communicators and teachers to convince the public of the basic facts, or are people so embedded in the now that even one unseasonal rain day can convince them - as it did some random man I met on the street - that climate change is a myth?