Atmospheric carbon dioxide concentrations climbed 2.28 parts-per-million (ppm) in 2008 to the highest level in at least 650,000 years — and possibly 20 million years — reports NOAA.
The average annual growth rate of CO2 concentrations this decade is now 2.1 ppm a year or 40 percent higher than that of the 1990s. CO2 emissions from the burning of fossil fuels are increasing at four times the rate of the previous decade.
The news comes shortly after a leading member of the Intergovernmental Panel on Climate Change warned that the impacts of climate change are likely to be far worse than projected in the most recent assessment by the Nobel Prize-winning group of scientists.
Some scientists, including James Hansen of NASA’s Goddard Institute for Space Studies, warn that CO2 levels must be kept below 350 ppm to avoid serious impacts from climate change. CO2 concentrations are presently around 386 ppm.