10 November 2006Catherine Brahic
Far from slowing down, global carbon dioxide emissions are rising faster than before, said a gathering of scientists in Beijing on Friday.
Between 2000 and 2005, emissions grew four times faster than in the preceding 10 years, according to researchers at the Global Carbon Project, a consortium of international researchers. Global growth rates were 0.8% from 1990 to 1999. From 2000 to 2005, they reached 3.2%.
Though alarming, the figures confirm expectations. "They make intuitive sense to me," says Jim Watson, deputy leader of the energy programme at the Tyndall Centre for Climate Change Research, UK.
One likely contributor is China, whose emissions slowed at end of the 1990s before rising again. China is now the world’s second largest emitter of greenhouse gases after the US. On Tuesday, the International Energy Agency released a report predicting that it would become the world’s top emitter by 2030 (see World faces 'dirty, insecure' energy future).
Other growing developing countries, such as India and Brazil, are also fast becoming large emitters.
The US, meanwhile, is taking no nationwide action to reduce greenhouse gas emissions. And the European Union Emissions Trading Scheme - created to help EU nations abide by their agreed Kyoto Protocol emissions limits - failed to do so in 2005, its first year of operation. It is unlikely to do so until its second phase of operation, which begins in 2008.
Unacceptably high
The Global Carbon Project report shows that carbon dioxide emissions over the last five years resembled one of the scenarios which the Intergovernmental Panel on Climate Change uses to predict how the world will change with greenhouse gas emissions. The “A1B” scenario assumes that 50% of energy over the next century will come from fossil fuels, resulting in atmospheric carbon dioxide concentrations causing drastic climatic consequences.
"On our current path, we will find it extremely difficult to rein in carbon emissions enough to stabilise the atmospheric CO2 concentration at 450 parts per million and even 550 ppm will be a challenge," says Josep Canadell, executive director of the Global Carbon Project.
Research suggests that stabilising carbon dioxide concentrations at 450 ppm could limit global warming to 2°C.
Environmental inertia
The authors also highlight the importance of environmental inertia. This is the mechanism by which the environment stores up part of the energy of generated by greenhouse gas emissions, only releasing it to the atmosphere later on.
As a result, even when human emissions do begin to drop, atmospheric carbon dioxide will continue to rise for up to a century. Global temperatures will continue to increase for two or more centuries.
"This report shows how important it is for all countries to work towards more ambitious climate targets within the next phase of international action beyond 2012," says Watson.
He adds: "Action to persuade the US and large developing countries such as China and India to work towards such an agreement is particularly crucial. So is the acceleration of technological co-operation initiatives to help developing countries - particularly China - to move to a lower carbon development pathway."
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