Read The Rational Optimist Online
Authors: Matt Ridley
What about malaria? Even distinguished scientists have been heard to claim that malaria will spread northwards and uphill in a warming world. But malaria was rampant in Europe, North America and even arctic Russia in the nineteenth and early twentieth century, when the world was nearly a degree cooler than now. It disappeared, while the world was warming, because people kept their cattle in barns (providing mosquitoes with an alternative dining option), moved indoors at night behind closed windows, and to a lesser extent because swamps were drained and pesticides used. Today malaria is not limited by climate: there are lots of areas where it could rampage but does not. The same is true of malaria’s mountain limitations. Just 2 per cent of Africa is too high for malarial mosquitoes now, and where highland areas have become malarial in the past century, such as in Kenya and New Guinea, the cause is human migration and habitat change, not climate change. ‘There is no evidence that climate has played any role in the burgeoning tragedy of this disease at any altitude,’ says Paul Reiter, a malaria expert. Should we not do something to prevent a million people dying of preventable malaria each year now, before worrying about the possibility that global warming might increase that number by 30,000 – at the very most? Likewise, a jump in tickborne disease in eastern Europe around 1990, initially blamed on climate change, turned out to be caused by the fact that people who lost their jobs after the collapse of communism spent more time foraging for mushrooms in the forests.
Many commentators seized on the World Health Organisation’s 2002 estimate that 150,000 people were dying each year as a result of climate change. The calculation assumed that an arbitrary 2.4 per cent of diarrhoea deaths were due to extra warmth breeding extra pathogenic bacteria; that some proportion of malaria deaths were due to extra rainfall breeding extra mosquitoes, and so on. But even if you accept these guesses, the WHO’s own figures showed that climate change was dwarfed as a cause of death by iron deficiency, cholesterol, unsafe sex, tobacco, traffic accidents and other things, not to mention ‘ordinary’ diarrhoea and malaria. Even obesity, according to the same report, was killing more than twice as many people as climate change. Nor was any attempt made to estimate the number of lives saved by carbon emissions – by the provision of electric power to a village where people suffer from ill health due to indoor air pollution from cooking over open fires, say, or the deaths from malnutrition prevented by the higher productivity of agriculture using fertiliser made from natural gas. In 2009 Kofi Annan’s Global Humanitarian Forum doubled the number of climate deaths to 315,000 a year, but only by ignoring these points, arbitrarily doubling the diarrhoea deaths caused by climate, and adding in ludicrous assumptions about how climate change was responsible for ‘inter-clan fighting in Somalia’, Hurricane Katrina and other disasters. Remember that every year fifty to sixty million people die: even going by the GHF figures less than 1 per cent of those die from climate change.
The global food supply will probably increase if temperature rises by up to 3°C. Not only will the warmth improve yields from cold lands and the rainfall improve yields from some dry lands, but the increased carbon dioxide will itself enhance yields, especially in dry areas. Wheat, for example, grows 15–40 per cent faster in 600 parts per million of carbon dioxide than it does in 295 ppm. (Glasshouses often use air enriched in carbon dioxide to 1,000 ppm to enhance plant growth rates.) This effect, together with greater rainfall and new techniques, means that less habitat will probably be lost to farming in a warmer world. Indeed under the warmest scenario, much land could revert to wilderness, leaving only 5 per cent of the world under the plough in 2100, compared with 11.6 per cent today, allowing more space for wilderness. The richest and warmest version of the future will have the least hunger, and will have ploughed the least extra land to feed itself. These calculations come not from barmy sceptics, but from the IPCC’s lead authors. And this is before taking into account the capacity of human societies to adapt to a changing climate.
The four horsemen of the human apocalypse, which cause the most premature and avoidable death in poor countries, are and will be for many years the same: hunger, dirty water, indoor smoke and malaria, which kill respectively about seven, three, three and two people per minute. If you want to do your fellow human beings good, spend your effort on combating those so that people can prosper, ready to meet climate challenges as they arrive. Economists estimate that a dollar spent on mitigating climate change brings ninety cents of benefits compared with $20 benefits per dollar spent on healthcare and $16 per dollar spent on hunger. Keeping climate at 1990 levels, assuming it could be done, would leave more than 90 per cent of human mortality causes untouched.
Saving ecosystems
Ah, but that is the human race. What about other species? Will the warmth cause a wave of extinctions? Perhaps, but not necessarily. So far, despite two bursts of twentieth-century warming, not a single species has unambiguously been shown to succumb to global climate trends. The golden toad of Costa Rica, sometimes cited as the first casualty, died out either from a fungal disease or because of the drying of its cloud forest, probably caused by deforestation on the lower slopes of its mountain home: a local, not a global cause. The polar bear, still thriving today (eleven of thirteen populations are growing or steady) but threatened by the loss of Arctic sea ice in high summer, may contract its range further north, but it already adapts to ice-free summer months in Hudson’s Bay by fasting on land till the sea re-freezes; and there is good evidence from northern Greenland of a briefly almost ice-free summer sea in the Arctic about 5,500 years ago, during a period that was markedly warmer than today. Arguably, the orang-utan, being devastated by the loss of forest to palm oil bio-fuel plantations in Borneo, is under greater threat from renewable energy than the polar bear is from global warming.
Do not get me wrong, I am not denying that species extinctions are occurring. I passionately believe in saving threatened species from extinction and I have twice worked on projects attempting to rescue endangered species – the cheer pheasant and the lesser florican. But the threats to species are all too prosaic: habitat loss, pollution, invasive competitors and hunting being the same four horsemen of the ecological apocalypse as always. Suddenly many of the big environmental organisations have lost interest in these threats as they chase the illusion of stabilising a climate that was never stable in the past. It is as if the recent emphasis on climate change has sucked the oxygen from the conservation movement. Conservationists, who have done tremendous good over the past half-century protecting and restoring a few wild ecosystems, and encouraging local people to support and value them, risk being betrayed by the new politicised climate campaigners, whose passion for renewable energy is eating into those very ecosystems and drawing funds away from their efforts.
Take coral reefs, which are suffering horribly from pollution, silt, nutrient runoff and fishing – especially the harvesting of herbivorous fishes that otherwise keep reefs clean of algae. Yet environmentalists commonly talk as if climate change is a far greater threat than these, and they are cranking up the apocalyptic statements just as they did wrongly about forests and acid rain. Charlie Veron, an Australian marine biologist: ‘There is no hope of reefs surviving to even mid-century in any form that we now recognise.’ Alex Rogers of the Zoological Society of London pledges ‘an absolute guarantee of their annihilation’. No wiggle room there. It is true that rapidly heating the water by a few degrees can devastate reefs by ‘bleaching’ out the corals’ symbiotic algae, as happened to many reefs in the especially warm El Niño year of 1998. But bleaching depends more on rate of change than absolute temperature. This must be true because nowhere on the planet, not even in the Persian Gulf where water temperatures reach 35°C, is there a sea too warm for coral reefs. Lots of places are too cold for coral reefs – the Galapagos, for example. It is now clear that corals rebound quickly from bleaching episodes, repopulating dead reefs in just a few years, which is presumably how they survived the warming lurches at the end of the last ice age. It is also apparent from recent research that corals become more resilient the more they experience sudden warmings. Some reefs may yet die if the world warms rapidly in the twenty-first century, but others in cooler regions may expand. Local threats are far more immediate than climate change.
Ocean acidification looks suspiciously like a back-up plan by the environmental pressure groups in case the climate fails to warm: another try at condemning fossil fuels. The oceans are alkaline, with an average pH of about 8.1, well above neutral (7). They are also extremely well buffered. Very high carbon dioxide levels could push that number down, perhaps to about 7.95 by 2050 – still highly alkaline and still much higher than it was for most of the last 100 million years. Some argue that this tiny downward shift in average alkalinity could make it harder for animals and plants that deposit calcium carbonate in their skeletons to do so. But this flies in the face of chemistry: the reason the acidity is increasing is that the dissolved bicarbonate is increasing too – and increasing the bicarbonate concentration increases the ease with which carbonate can be precipitated out with calcium by creatures that seek to do so. Even with tripled bicarbonate concentrations, corals show a continuing increase in both photosynthesis and calcification. This is confirmed by a rash of empirical studies showing that increased carbonic acid either has no effect or actually increases the growth of calcareous plankton, cuttlefish larvae and coccolithophores.
My general optimism is therefore not dented by the undoubted challenge of global warming by carbon dioxide. Even if the world warms as much as the consensus expects, the net harm still looks small alongside the real harm now being done by preventable causes; and if it does warm this much, it will be because more people are rich enough to afford to do something about it. As usual, optimism gets a bad press in this debate. Optimists are dismissed as fools, pessimists as sages, by a media that likes to be spoon-fed on scary press releases. That does not make the optimists right, but the poor track record of pessimists should at least give one pause. After all, we have been here before. ‘I want to stress the urgency of the challenge,’ said Bill Clinton once: ‘This is not one of the summer movies where you can close your eyes during the scary parts.’ He was talking not about climate change but about Y2K: the possibility that all computers would crash at midnight on 31 December 1999.
Decarbonising the economy
In short, a warmer and richer world will be more likely to improve the well-being of both human beings and ecosystems than a cooler but poorer one. As Indur Goklany puts it, ‘neither on grounds of public health nor on ecological factors is climate change likely to be the most important problem facing the globe this century.’ The results of thirteen economic analyses of climate change, assuming consensus amounts of warming, conclude that it will either add or subtract about one year of global economic growth in the second half of the twenty-first century. Critics of this view often argue that development and carbon reduction need not be alternatives, and that it is the poor who are hit hardest by climate change. True, but it is a point that cuts both ways – it is the poor who are hit hardest by high energy costs, too. If mismanaged, climate mitigation could prove just as damaging to human welfare as climate change. A child that dies from indoor smoke in a village denied fossil-fuel electricity is just as great a tragedy as a child that dies in a flood caused by climate change. A forest that is cut down by people deprived of fossil fuels is just as felled as one lost to climate change. If climate change proves to be mild but cutting carbon causes real pain, we may find we have stopped a nose bleed by putting a tourniquet round our neck.
And cutting carbon will mean costly energy: so says the IPCC. If I am to accept the IPCC’s estimate of temperature rise for the sake of this argument, then I should also accept its estimate of the cost of carbon rationing – which it puts at 5.5 per cent of GDP after about 2050, and that is after making highly unlikely assumptions of (quoting from the IPCC’s 2007 report) ‘transparent markets, no transaction costs, and thus perfect implementation of policy measures throughout the twenty-first century, leading to the universal adoption of cost-effective mitigations measures, such as carbon taxes or universal capand-trade programmes’.
The world economy needs plentiful joules of energy if it is not to run on slaves, and at the moment by far the cheapest source of those joules is the burning of hydrocarbons. About 600 kilograms of carbon dioxide are emitted per thousand dollars of economic activity. No country ‘is remotely on a path’ towards cutting that number substantially, says the physicist David MacKay. It could be done, but only at vast cost. The cost would be environmental as well as financial. Take Britain, an ‘average rich’ country. Burning hydrocarbon still provides 106 of the 125 kilowatt-hours per day per person of work that give Britons their standard of living. How could Britain power itself without fossil fuels? Suppose that an aggressive and expensive plan of pumped heat, waste incineration and loft insulation knocks twenty-five of that demand off, leaving 100kWh per day to find. Divide that 100 in four and ask for twenty-five from nuclear, twenty-five from wind, twenty-five from solar and five each from biofuel, wood, wave, tide and hydro. What would the country look like?
There would be sixty nuclear power stations around the coasts, wind farms would cover 10 per cent of the entire land (or a big part of the sea), there would be solar panels covering an area the size of Lincolnshire, eighteen Greater Londons growing bio-fuels, forty-seven New Forests growing fast-rotation harvested timber, hundreds of miles of wave machines off the coast, huge tidal barrages in the Severn estuary and Strangford Lough, and twenty-five times as many hydro dams on rivers as there are today. The prospect is unappetising: the entire country would look like a power station, pylons would march across the uplands and convoys of trucks would cart timber along the roads. Power cuts would be frequent – imagine a still, cold foggy day in January when the slack tide in the Severn estuary coincides with peak demand, when the solar panels are dead and the wind turbines still. Wildlife would suffer from the loss of estuaries, free-flowing rivers and open country. Powering the world with such renewables now is the surest way to spoil the environment. (Of course, coal mining and oil drilling can and do spoil the environment, too, but compared with most renewables their footprints are surprisingly small for the energy they yield.)