May 16, 2006
|CO2 Growth "Unprecedented"||Environment|
In the past, the oceans and the biosphere have modulated CO2 increases by absorbing CO2. There are now signs, however, that the Earth's capacity for CO2 absorption may be getting overwhelmed. SMH (via Big Gav at Peak Energy):
The global level of carbon dioxide in the atmosphere has alarmed scientists by growing strongly for the last four years in a row.
"That's unprecedented," said Paul Fraser, chief research scientist at the CSIRO's Marine and Atmospheric Research division.
Describing the trend as "a clear manifestation" of the world's increasing hunger for fossil fuels, Dr Fraser said: "We are in line for the carbon dioxide future that we hope to avoid, a one-to-three degree rise in temperatures over the next century."
Last year carbon dioxide levels grew by two parts per million, or 0.54 per cent, twice the rate of the early 1980s. Atmospheric nitrous oxide, produced by fertilisers and land clearing, also soared last year, rising one part per billion, or 0.3 per cent.
And artificial greenhouse gases, including hydrofluoro-carbons, introduced during the 1990s to replace chlorofluorocarbons, set a growth record, up seven parts per trillion, a 5.3 per cent increase.
The CSIRO said 2005 "was a record for increases in green-house gas heating, the main driver of increasing surface temperatures". Dr Fraser said that with carbon dioxide emissions, "normally we have one or two years of high growth, followed by one or two years of lower growth". This comes from the oceans and the biosphere - including trees and plants - soaking up enough of the gas to take the edge off increases.
However, sampling by the Bureau of Meteorology in Tasmania showed the normal pattern of higher and lower growth rates, called modulation, had failed to appear in the last four years. Instead, annual carbon dioxide increases had been consistently above average. "That's a surprise," said Dr Fraser, adding it would be extraordinary if the modulating effect of the oceans and the biosphere failed to kick in this year. However, the environment's ability to absorb the gas could eventually be overwhelmed. The only solution was "emitting less carbon dioxide", he said. [Emphasis added]
Yet another sign that harmful feedback loops are kicking in: global warming is only going to accelerate if we don't cut CO2 emissions, and quickly. We can all do what we can as individuals, but the essential missing ingredient is leadership. We should have elected Al Gore when we had the chance. No wait — we did.