The Weather Makers: the History & Future Impact of Climate Change
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Tiiran_in<Dfi?l*i_i v<?sTiîi_rqj{_1iâaiTie w.fl. latfcncu lanaTsywäwauuatUAin .nauriirhufanwiî_i>rmn mis uawjnwn mon awvrssn-fiTqjcplaBaviB W.U. laffmeif (W%T12flJ{_£_W) ianai-TOU.n.n_iä_n.wa_ßyifi0™y»rcn^ an.efä'JiJljiJafrijJuyiuf^f^YifrfN^ a-huönfhifiauuaan^nmanrvä KINGDOM OF THAILAND Copyright Act, BE 2537(1994) WARNING This material has been reproduced and communicated to you pursuant to Sections 32 and 33 of the Copyright Act, BE 2537 (1994) (The Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. DO NOT REMOVE THIS NOTICE Tim Flannery, The weather makers: the history & future impact of climate change (Penguin, 2005), pp69-79 and 267-306. EIGHT DIGGING UP THE DEAD We walk on earth, we look after, like rainbow sitting on top. But something underneath, under the ground. We don't know. You don't know. What do you want to do? If you touch, you might get cyclone, heavy rain or flood. Not just here, you might kill someone in another place. Might be kill him.in another country. You cannot touch him. Big Bill Neidjie, Gagadju Man, 2001. Australia's Aborigines live close to the land, and they have a distinctive way of seeing the world. Instead of viewing things like mining, the weather and biodiversity in isolation, they tend to see a whole picture. Big Bill Neidjie was a truly wise elder who spent his youth living a tribal life in intimacy with the land. When he tells us about the impact of mining in his Kakadu country he doesn't talk of the mines, the tailings and the poisoned earth. In just a handful of words he describes the great cycle ïv. f 70 GAIA'S TOOLS that runs from disturbing the eternal living dreaming of the ancestors to the catastrophe awaiting unborn generations. The challenge he throws tjown—'What do you want to do?'—is discomforting, because by profaning Earth and touching what lies below we have already provided an answer. My country—Bill's country—is pierced through and through with mines of every type, and more coal is drawn from its innards to be shipped off overseas than from any other place on the planet Because uranium mines have been developed on parts of Big Bill's land that are rich in myth and tradition, he was probably thinking of uranium rather than coal when he composed his epic poem. Yet in them he has intuited the hidden links between mining, climate change and human weUbeing that scientists have groped towards as they seek to understand the greenhouse effect. Bill's challenge remains there to be answered, because we still have a chance to decide our future. But first we need to learn a little of the history, nature and power ofthat black stone, coal, and of its slippery ally, oil. Fossil fuels—oil, coal and gas—are all that remain of organisms that, many millions of years ago, drew carbon from the atmosphere. When we burn wood we release carbon that has been out of atmospheric circulation for a few decades, but when we burn fossil fuels we release carbon that has been out of circulation for eons. Digging up the dead in this way is a particularly bad thing for the living to do. In 2002, the burning of fossil fuels released a total of 21 billion tonnes of C02 into the atmosphere. Of thisj coal contributed 41 per cent, oil 39 per cent, and gas 20 per cent.17* These percentages, however, don't reflect the tonnages burned, fpr some fuels contain more carbon than others. The energy we liberate when we burn these fuels comes from carbon and hydrogen. Because carbon causes climate change, the more carbon-rich a fuel is, the more danger it presents to humanity's future. Apart from the impur ides it contains, several of which (such as sulphur and mercury) are potent pollutants, the best black coal is almost pure carbon. Burn a tonne of it and you create 3.7 tonnes of C02. The fuels derived from oil 3K DIGGING UP THE DEAD 71 are less carbon rich, containing two hydrogen atoms for every one of carbon in their structure. Because hydrogen is a source of energy which produces more heat when burned than carbon (and in doing so produces only water), burning oil releases less C02 per unit used than coal. The fossil fuel with the least carbon content is methane, which has just one carbon atom for every four hydrogen atoms. These fuels thus form a stairway leading away from carbon as the fuel for our economy. The efficiency with which power is generated by burning a fuel is also an important factor in determining how; much COz is produced. Even using the most advanced methods (and most coal-fired power plants come nowhere near this), burning anthracite to generate electricity results in 67 per cent more C02 emissions than does methane, while brown coal (which is younger, and has more moisture and impurities) produces 130 per cent more.118 From a climate change perspective, then, there's a world of difference between using gas or coal to power an economy. Coal is our planet's most abundant and widely distributed fossil fuel. Those in the industry often refer to it as 'buried sunshine', and in a sense this is an accurate description, for coal is the fossilised remains of plants that grew in swamps millions of years ago. In places like Borneo you can see the inidal stages of the coal-forming process taking place. There, huge trees topple over and sink into the quagmire, where a lack of oxygen impedes rotting. More and more dead vegetation builds up until a thick layer of sodden plant matter is in place. Rivers then wash sand and silt into the swamp, which compresses the vegetation, driving out moisture and other impurities. As the swamp is buried deeper and deeper in the earth, heat and time alter the chemistry of the wood, leaves and other organic matter. First, the peat is converted to brown coal and, after many millions of years, the brown coal becomes bituminous coal. If further pressure and heat are applied, and more impurities removed, it can finally become anthracite, and at its most exquisite anthracite—in the form of jet—is a beautiful jewel, as pure a carbon treat as a diamond. Certain times in Earth's history have been more propitious for forming 72 GAIA'S TOOLS | : -c -j coal than others. The Eocene Period, around 50 million years ago, was ' one such time. Then, great swamps lay over parts of Europe and Australia, the buried remains of which form the brown coal deposits found there today. Because it is full of impurities, and is often so wet that some of it must be burned just to dry the fuel that enters the furnaces, brown coal is the most polluting of all fuels. It is also unprofitable to trade: if you want coal that will repay the cost of transport, you must turn to bituminous coal or anthracite. Much of the world's anthracite lived during the Carboniferous Period, 360 to 290 million years ago. Named for the immense coal deposits that were then laid down over much of the world, the Carboniferous world was a very different place from the wedands of today. If you'd been able to punt through the ancient swamps ofthat bygone era, instead of swamp cypress and the like, you would have seen gigantic relatives of clubmosses and lycopods, as well as far stranger plants that are now extinct. The scaly, columnar trunks of the Lepidodendron grew in dense forests, each trunk two metres in diameter and soaring forty-five metres into the air. They did not branch until near their tips, where a few short, straggly sproutings bore metre-long grassy leaves. In other places the barrel-like Sigillaria grew, a bifurcated plant six metres tall, while gigantic horsetail ferns and seed-ferns made up the remainder of the arborescent flora.87 There were no reptiles, mammals or birds in those long ago times. Instead, the stifling, humid growth teemed with insects and their kin. The atmosphere then was rich in oxygen, which allowed creatures with inefficient breathing apparatus to grow to immense size. Millipedes grew to two metres in length, and spiders reached a metre across. Thirty-centi metre-long cockroaches shared the verdure with dragonflies whose wingspans approached a metre, while in the waters below lurked croco dile-sized amphibians with huge heads, wide mouths and beady eyes. In pilfering the buried bounty of this alien world we have set ourselves free from the limits of biological production in our present age. DIGGING UP THE DEAD 73 The march towards a fossil-fuel-dependent future started in the England of Edward I, though his subjects only reluctandy turned away from the sweet scent of the burning timber that had fed hearths for centu ries. The King himself so detested the smell of coal that in 1306 he banned the burning of it in his kingdom, threatening offenders with 'great fines and ransoms'. There are even records of coal burners being tortured, hanged or decapitated (sources don't agree on the punishment—it's possible all three were applied). But England's forests were becoming exhausted, and as the price of timber rose the English became the first Europeans to burn coal on a large scale.