Emissions from burning fossil fuels have increased about 3 per cent a year since 2000, up from 1 percent a year during the 1990s, said Australia's peak scientific body, the Commonwealth Scientific and Industrial Research Organisation (CSIRO).
''A major driver of the accelerating growth rate in emissions is that, globally, we're burning more carbon per dollar of wealth created,'' CSIRO scientist Mike Raupach said in a statement.
''It means that climate change is occurring faster than has been predicted by most of the studies done through the 1990s and into the early 2000s,'' he said.
Raupach led an international team of carbon-cycle experts, emissions experts and economists, brought together by the CSIRO's Global Carbon Project, to quantify global carbon emissions and demand for fossil fuels.
The report found nearly 8 billion tonnes of carbon were emitted globally into the atmosphere as carbon dioxide in 2005, compared with just 6 billion tonnes in 1995.
''As countries undergo industrial development, they move through a period of intensive, and often inefficient, use of fossil fuel,'' said Raupach.
''Efficiencies improve along this development trajectory, but eventually tend to level off. Industrialised countries such as Australia and the U.S. are at the levelling-off stage, while developing countries such as China are at the intensive development stage.'' Since the start of the industrial revolution, the United States and Europe account for more than 50 percent of global emissions over two centuries, while China accounts for less than 8 per cent, said the CSIRO report.
The 50 least-developed nations contributed less than 0.5 per cent of global emissions over 200 years, it said.
On average, each person in Australia and the United States now emits more than 5 tonnes of carbon per year, while in China the figure is 1 tonne per year, said the report.
''In addition to reinforcing the urgency of the need to reduce emissions, an important outcome of this work is to show that carbon emissions have history,'' said Raupach.
''We have to take both present and past emissions trajectories into account in negotiating global emissions reductions. To be effective, emissions reductions have to be both workable and equitable,'' he said.
The CSIRO report found Australia's per capita emissions were amongst the highest in the world due to a heavy reliance on fossil-fuel generated electricity and a dependence on cars and trucks for transport.
''That means that we have quite a way to go in terms of reducing our emissions to bring about CO2 stabilisation,'' said Raupach.
''Our own improvements in the energy efficiency of the economy ...
have been not as rapid as improvements in other developed countries.'' Australia, like close ally the United States, refuses to sign the Kyoto Protocol setting caps on greenhouse gas emissions, and has called for a global scheme to replace ''Old Kyoto''.
Both countries say the pact is unworkable because it excludes big developing nations such as India and China from binding targets during the treaty's first phase, which ends in 2012. China is the world's second top emitter of carbon dioxide after the United States.
Negotiations have yet to start in earnest on shaping Kyoto's next phase, with India and China strongly opposed to binding targets and demanding rich nations, particularly the United States, commit to deep reductions in emissions.
REUTERS AE SSC1057