From The Guardian.co.uk
Scientists warned last night that global warming will be "stronger than expected and sooner than expected", after a new analysis showed carbon dioxide is accumulating in the atmosphere much faster than predicted.
Experts said that the rise was down to soaring economic development in China, and a reduction in the amount of carbon pollution soaked up by the world's land and oceans. It also means human emissions will have to be cut more sharply than predicted to avoid the likely effects...
Dr Le Quere said: "We are emitting far more than anticipated when the IPCC scenarios were drawn up in the late 1990s." Global carbon dioxide emissions from fossil fuel burning has risen by an average 2.9% each year since 2000. During the 1990s the annual rise was 0.7%.
The new study explains abnormally high carbon dioxide measurements highlighted by the Guardian in January. At the time, scientists were puzzled why dozens of measuring stations across the world were showing a CO2 spike for 2006, the fourth year in the last five to show a sharp increase in the greenhouse gas.
Carbon dioxide concentration in the atmosphere is measured in parts per million (ppm); from 1970 to 2000, the concentration rose by about 1.5ppm each year; since 2000 the annual rise has leapt to an average 1.9ppm.
The new study, published in the US journal Proceedings of the National Academy of Sciences (PNAS), says three processes have contributed to this increase: growth in the world economy, heavy use of coal in China, and a weakening of natural "sinks" - forests, seas and soils that absorb carbon.
Pep Canadell, executive director of the Global Carbon Project, which carried out the research, said: "In addition to the growth of global population and wealth, we now know that significant contributions to the growth of atmospheric CO2 arise from the slowdown of natural sinks and the halt to improvements in the carbon intensity of wealth production."
The overall growth of the economy is the only one of the three factors accounted for in scientists' forecasts of climate change, which means the growth in atmospheric CO2 is about 35% larger than they expected...
Scientists assume about half of human carbon emissions are reabsorbed into the environment, but computer models predictincreased temperatures will reduce this effect...