612Kyoto promises are nothing but hot air
- Jun 26, 2006
Kyoto promises are nothing but hot air
MANY governments, including some that claim to be leading the fight against global warming, are harbouring a dirty little secret. These countries are emitting far more greenhouse gas than they say they are, a fact that threatens to undermine not only the shaky Kyoto protocol but also the new multibillion-dollar market in carbon trading.
Under Kyoto, each government calculates how much carbon dioxide, methane and nitrous oxide its country emits by adding together estimated emissions from individual sources. These so-called "bottom-up" estimates have long been accepted by atmospheric scientists, even though they have never been independently audited.
Now two teams that have monitored concentrations of greenhouse gases in the atmosphere say they have convincing evidence that the figures reported by many countries are wrong, especially for methane. Among the worst offenders are the UK, which may be emitting 92 per cent more methane than it declares under the Kyoto protocol, and France, which may be emitting 47 per cent more.
Peter Bergamaschi of the European Commission Joint Research Centre at Ispra, Italy, used an alternative "top-down" technique to study emissions across Europe. His technique is to measure in detail how concentrations of greenhouse gases vary across the globe. Levels are generally higher near major sources such as industrial centres, and when weather conditions trap the pollution. They are lower near natural "sinks" such as cold areas of ocean. Concentrations can also vary widely depending on factors such as the weather. Over London, for example, methane levels vary from 1800 parts per billion (ppb), the global background level, on windy days to upwards of 3000 ppb when local emissions from landfills and gas pipelines are trapped by cold night air.
By measuring these differences and tracking air movements, the scientists say they can calculate a country's emissions independently of government estimates. Bergamaschi's calculations suggest that the UK emitted 4.21 million tonnes of methane in 2004 compared to the 2.19 million tonnes it declared, while France emitted 4.43 million tonnes compared to the 3.01 million tonnes it declared. Methane is an extremely powerful greenhouse gas. While it persists in the atmosphere for only one-tenth as long as CO2, its immediate warming effect, tonne for tonne, is around 100 times greater. According to some estimates, methane is responsible for a third of current global warming, and reductions in methane emissions may be the quickest and cheapest way of slowing climate change.
Bergamaschi's figures are based on real atmospheric measurements that integrate emissions over large areas. While he admits that they cannot be entirely accurate, they are free from some of the sources of error that apply to national declared figures, which are based on uncertain extrapolations from sites such as landfills, whose emissions are highly variable.
During the course of Bergamaschi's study, the German government revised its estimate of national methane emissions upwards by some 70 per cent, placing it close to his estimate. The British and French governments continue to stick with their low estimates. Bergamaschi told New Scientist that the UK appears to be badly under-reporting methane bubbling out of landfill sites, while France's emissions seem to be generally under-reported. On the other hand, Ireland and Finland may be overestimating emissions from peat bogs.
Bergamaschi's calculations are supported by a similar study led by Euan Nisbet of Royal Holloway University of London, who is a member of the Global Atmosphere Watch (GAW), a network of atmospheric scientists organised by the UN's World Meteorological Organization. Nisbet estimates that methane emissions in the London area in the late 1990s were 40 to 80 per cent higher than declared by the government at the time.
Both scientists believe that countries outside Europe are also likely to be under-reporting their emissions, and that the problem is global. "We know the total global emissions well enough, but individual national numbers may be badly out. Some are too big and some are too small," Nisbet says.
In the past, he says, estimates of greenhouse gas emissions were inaccurate simply because of the difficulty of measuring them, but that may have changed. "Now that money enters the picture, with the Kyoto protocol rules and carbon trading, so also can fraud. There will be an incentive to under-report emissions." Nisbet, Bergamaschi and other scientists now want to create a global system for auditing emissions claims by directly measuring concentrations of greenhouse gases in the air.
Most existing monitoring sites are intended to measure background gas levels in clean ocean and mountain air. The oldest and most famous is on top of Mauna Loa in Hawaii, where US researcher David Keeling first proved half a century ago that CO2 levels in the air were rising. The network now run by GAW is far from comprehensive: it includes just one station in China, sited on the relatively unpolluted Tibetan plateau, while India's sole site is in the unpolluted mountainous Ladakh region. There is no continuous monitoring in inland Africa, and only a few stations in South America and south-east Asia. Yet these regions support more than half the world's population and are responsible for a growing proportion of its greenhouse gas emissions.
Some western governments, say the scientists, have been reluctant to set up permanent monitoring stations. "Of all the G8 nations, the UK does the least," says Nisbet, who runs the only permanent monitoring point in England, from his lab near Egham, on the south-western fringes of London. The longest-running CO2 monitoring point on British soil, in the Shetland Islands, was run by Australia till 2001 and is now funded by Germany. France runs a network of monitors on its remote island territories round the world, but the UK government refuses pleas for it to do likewise on territories such as Ascension Island or South Georgia in the remote South Atlantic, or the Chagos Islands in the Indian Ocean. The European Union recently shut down its pioneering programme of measuring atmospheric methane across the continent. "Ironically, the best monitoring is done by the US and Australia, which are both in denial over Kyoto," Nisbet says.
The GAW scientists say that a global greenhouse gas monitoring network should provide open access to the information it collects. Only then, they say, will it be possible to do independent calculations to discover who is emitting what, and test which countries are complying with Kyoto and making accurate claims about their emissions. Until such a network is in place, it will be all too easy for nations such as the UK to talk green while acting dirty.
From issue 2557 of New Scientist magazine, 22 June 2006, page 10
Sins of Omission?
The most alarming failure of greenhouse gas emissions reporting is thought to have occurred in China, the world's second largest emitter. In the late 1990s, when its economy was growing by 10 per cent a year, the Chinese government reported a dramatic fall in CO2 emissions to the UN climate change convention. It declared that, after a long period of steep increases, emissions had fallen from 911 million tonnes of carbon a year in 1996 to 757 million tonnes in 2000, a drop of 17 per cent.
China said the fall in emissions was achieved by burning less coal, an assessment it based on a decline in coal production. Some analysts praised the country for using coal more efficiently, but that picture was called into doubt when declared coal production and emissions estimates resumed their fast rise. Estimates for 2004 put China's CO2 emissions above 1200 million tonnes.
Most analysts now conclude that the drop in emissions was entirely illusory. It coincided with major changes in the organisation of the Chinese coal industry, which replaced state targets with a market system. "Emissions figures before 1996 were inflated because mine officials had production targets to meet, and declared they had met them when they had not," one analyst told New Scientist. By 2000, this effect had gone, and "subsequent figures for CO2 emissions are probably more accurate as a result." While the Chinese government may not have intentionally misled the international community over its emissions at the time, the incident reveals how easy it could be to fiddle official figures.
Source: New Scientist
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