Tuesday, 23 May 2017

Water, water, everywhere: the hidden holism of H2O

Like other northern regions of New Zealand, the summer of 2017 saw Auckland residents facing City Council requests to conserve water, as well as a hosepipe ban in effect during March and April. It therefore seems ironic that the water shortage occurred at the same time as flooding in the west of the city; thanks to a tropical downpour - one of several so far this year - the equivalent of an entire month's rain fell over a day or two. Clearly, water shortages are going to become an ever-increasing issue, even in nations with well-developed infrastructure.

The British historian of science James Burke, writer-presenter of The Day the Universe Changed, also made three television series called Connections 1, 2 and 3 (in 1978, 1994 and 1997 respectively) which examined the historical threads linking scientific and technological advances with changes in other areas of society. Therefore I'd like to take a similarly holistic approach to the wonderful world of water consumption and see how it ties into the world in general.

Although the statistics vary - it's difficult to assess with any great precision - there are published figures suggesting that the populace of richer nations use up to 5000 litres of water each per day, mostly hidden in food production. Many websites now supply details of the amount of water used to grown certain crops and foodstuffs, so you can easily raise your guilt level simply by comparing your diet to the water involved in its generation; and that's without considering the carbon mileage or packaging waste, either!

I've previously discussed the high environmental cost of cattle farming, with both dairy and beef herds being prominent culprits in water pollution as well as consumption. However, there are plenty of less-obvious foodstuffs proven to be notorious water consumers, for example avocado and almonds. Although the latter might be deemed a luxury food, much of the global supply is now used to make almond milk; with consumption increasing up to 40% year-on-year, this is one foodstuff much in demand.

Even though it is claimed to require much less water than the equivalent volume of dairy produce, almond farming is still relevant due to the massive increase in bulk production, especially in California (home to 80% of the global almond harvest). The reasons for the popularity of almond milk are probably two-fold: firstly, the public is getting more health-conscious; and secondly, a reduction or abstention in dairy produce is presumed to lessen food allergies/intolerance. These obviously link to prominent concerns in the West, in the form of high-calorie/low-exercise diets leading to mass obesity and over-use of cleaning chemicals in the home, preventing children from developing good anti-microbial resistance. Clearly, there is a complex web when it comes to water and the human race.

Even for regions chronically short of water such as California, more than three-quarters of fresh water usage is by agriculture. In order to conserve resources, is it likely that we may soon face greater taxes on commercially-grown water-hogging produce and bans on the home-growth of crops that have a low nutrition to water consumption ratio? I've recently read several books discussing probable issues over the next half century with the humble lettuce appearing as a good example of the latter.

Talking of which, the wet and windy conditions in New Zealand of the past year - blamed at least partially on La Niña - have led to record prices for common vegetables: NZ$9 for a lettuce and NZ$10 for a cauliflower, even in major supermarket chains. British supermarkets were forced to ration some fruit and vegetables back in February, due to their Mediterranean growers suffering from storms and floods. This suggests that even for regions with sophisticated agricultural practices there is a fine line between too much and too little fresh water. Isn't it about time that the main food producers developed a more robust not to mention future-proof infrastructure, considering the increased impact that climate change is likely to have?

The world is also paying a heavy price for bottled water, a commercial enterprise that largely breaks all boundaries of common sense. In the USA alone it costs several thousand times the equivalent volume of tap water and there are some reports that there may be chemical leaching from reusing plastic bottles. As you might expect, there is also an extremely high environmental cost. This includes the fossil fuels used by bottling plants and transportation, the lowering of the water table (whose level is so critical in areas utilising less sophisticated farming technologies) and the impact of plastic waste: the USA only recycles about 23% of its plastic water bottles, resulting in 38 billion bottles dumped each year at a cost of around US$1 billion. All in all, bottled water for nations with highly developed infrastructure seems like an insane use of critical resources.

Although accelerated population growth has become a widespread fear, there are indicators that later this century the global figure may peak at around nine billion and then level off. Increasing urbanisation is seen a primary cause for this and not just in developing nations; Auckland for example (New Zealand's largest city by far) experienced 8% population growth in the seven years from 2006. A larger population obviously requires more food, but a more urban and therefore generally better educated, higher income populace tends to demand access to processed, non-local and above all water-intensive foods. China is the touchstone here, having seen a massive increase in fish and meat consumption over the past half century; the latter has risen from 8 million tons per year in 1978 to over 70 million tons in recent years.

It has been claimed that 70% of industrial waste generated in developing nations is dumped into water courses, meaning that there will be a massive cost for environmental clean-up before local sources can be fully utilised. The mass outbreak of E-coli in Hawke's Bay, New Zealand, in February this year shows that even developed nations are having difficulty maintaining water quality, whilst there has been a shocking admittance of lead contamination above safe levels in 41 American states over the past three years. Does this mean bottled water - heretofore the lifeline of Western tourists abroad - is becoming a necessity in the West after all?

Some might argue that thanks to global warming there will be more water available due to the melting of polar caps and glaciers, which after all contain almost two-thirds of the world's fresh water resources. However, these sources are mostly located far from high-density populations and upon marine contamination they require energy-demanding desalination technology. It's small comfort that current estimates suggest that by 2025 about 14% of the global population will rely on desalination plants for their fresh water needs.

In the West we tend to take clean, safe water completely for granted but thanks to the demands of living in a society run on rampant consumerism - coupled with poor science education - everyday decisions are being made that affect the environment, waste critical resources and damage our own health. Pundits are predicting that water will be the new oil: liquid gold, a precious commodity to be fought over, if necessary. Surely this is one resource that all of us can do something to support, whether it is cutting down on water-intensive foodstuffs, using tap rather than bottled water, or simply turning off a tap sooner than usual!

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?