Deborah Smith, Science Editor
November 28, 2006
Global efforts to reduce carbon dioxide emissions have had little impact with the rate of emissions more than doubling since the 1990s.
CSIRO Marine and Atmospheric Research scientist, Mike Raupach, said that from 2000 to 2005, the growth rate of carbon dioxide emissions was more than 2.5 per cent per year. "In the 1990s it was less than one per cent per year."
In 2005, 7.9 billion tonnes of carbon were emitted into the atmosphere as carbon dioxide.
This was near the high end of the fossil fuel use scenarios considered by the Intergovernmental Panel on Climate Change (IPCC), said Dr Raupach, who is also co-chair of the Global Carbon Project, an international scientific collaboration to study the carbon cycle.
"On our current path, it will be difficult to reign in carbon emissions enough to stabilise the atmospheric carbon dioxide concentration at 450 ppm," he said.
While China had the highest current growth rate in emissions, its emissions per person were still below the global average and its accumulated contribution since the start of the industrial revolution more than 200 years ago was only five per cent of the global total.
By comparison, the US and Europe have each contributed more than 25 per cent of accumulated global emissions.
Paul Fraser, also from CSIRO Marine and Atmospheric Research, said the findings were supported by measurements of carbon dioxide levels in the air, which grew by two parts per million in 2005.
This was the fourth year in a row of above-average growth, Dr Fraser said. "To have four years in a row of above-average carbon dioxide growth is unprecedented."
The two scientists presented their latest findings at a meeting at Tasmania's Cape Grim Baseline Air Pollution Station, which is run by CSIRO and the Australian Bureau of Meteorology.
Dr Fraser said the 30-year record of air collected at Cape Grim, showed growth rates of carbon dioxide were slightly more than one part per million in the early 1980s, but in recent years carbon dioxide levels has increased at almost twice this rate.
"The trend over recent years suggests the growth rate is accelerating, signifying that fossil fuels are having an impact on greenhouse gas concentrations in a way we haven't seen in the past."
CO2 BubblesAtmospheric scientists warn that greenhouse gas emissions are increasing more rapidly, despite global efforts to curb the use of fossil fuels, new research by Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO) shows.

According to CSIRO research scientist Dr Mike Raupach, 7.9 billion tonnes of carbon were emitted into the atmosphere as carbon dioxide in 2005 -  a doubling in the rate of increase since 1990 - and the rate of increase continues to accelerate.

Data from the Cape Grim air pollution monitoring station in north-west Tasmania shows carbon dioxide emissions have increased by 2.5% each year for the past five years. "From 2000 to 2005, the growth rate of carbon dioxide emissions was more than 2.5% per year, whereas in the 1990s it was less than 1% per year," Dr Raupach says. 

Dr Raupach, who co-chairs the international  Global Carbon Project also, was surprised by his research results. "It shows recent efforts globally to reduce emissions have had little impact on emissions growth," he said. The CSIRO found that in global terms, China has the highest current growth rate in CO2 emissions although it's emissions per person are below the global average. China's accumulated contribution since the start the 1800s is only five per cent of the global total. The USA and Europe have each contributed more than 25% of accumulated global emissions. 

Carbon dioxide concentrations in the atmosphere — a separate measure to carbon emissions — had also increased at an unprecedented rate. Dr Paul Fraser, also from CSIRO Marine and Atmospheric Research, said that atmospheric concentrations of carbon dioxide grew by two parts per million in 2005, the fourth year in a row of above-average growth. "To have four years in a row of above-average carbon dioxide growth is unprecedented," Dr Fraser said. 

He said the trend over recent years suggests the growth rate is accelerating, "signifying that fossil fuels are having an impact on greenhouse gas concentrations in a way we haven’t seen in the past."