According to the new study, carbon released from burning fossil fuel and making cement rose from 7.0 billion metric tonnes per year in 2000 to 8.4 billion metric tonnes in 2006. A metric tonne is 1,000 kilograms.
The growth rate increased from 1.3 per cent per year in 1990-1999 to 3.3 per cent per year in 2000-2006, the researchers added.
Trenberth noted that carbon dioxide is not the whole story; methane emissions have declined, so total greenhouse gases are not increasing as much as carbon dioxide alone. Also, he added, other pollution plays a role by cooling.
There are changes from year to year in the fraction of the atmosphere made up of carbon dioxide and the question is whether this increase is transient or will be sustained, he said.
"The theory suggests increases in (the atmospheric fraction), as is claimed here, but the evidence is not strong," Trenberth said.
The paper looks at a rather short time to measure a trend, Robock added, "but the results they get certainly look reasonable, and much of the paper is looking at much longer trends."
The research was supported by Australian, European and other international agencies.
http://www.thestar.com/article/269265 [Proofreader’s note: this article was edited for spelling and typos on October 23, 2007]
Stumble It!
Note that the report does not actually tell us what increase there is with respect to atmospheric CO2 (if any), the report only tells us that there's an increase in CO2 emissions, i.e. the production of CO2 from human related activities.
It is interesting that the report does not connect emission levels with actual atmospheric CO2 levels, and I am left wondering if CO2 levels are increasing or not, and if increasing by how much.
I wonder how many people walk away from reading this report with the incorrect assumption that atmospheric levels of CO2 have increased by 35% since 1990?