The Context of carbon dioxide in the air, 2006-2007.
Carbon
dioxide gas levels measured at 315
ppm in 1958, and 381 ppm in
2005, increased 76 ppm in 47 years, or a 1.607 ppm / annum average. ÒTodayÉthat is higher than we have
been for over a million yearsÓ
Shukman,
David. ÒSharp rise in CO2 levels recorded,Ó Tuesday, 14 March 2006, 00:12
GMT. BBC science correspondent
quotes Sir David King, above.
Parts
per million is ppm.
http://newsvote.bbc.co.uk/mpapps/pagetools/print/news.bbc.co.uk/1/hi/sci/tech/4803460.stm
for recent data, see -- http://www.cmdl.noaa.gov/ccgg/trends/co2_data_mlo.php;7-4-06,
What do the current levels mean in terms of policy
choices?
Hansen, Jim. ÒThe Threat to the Planet,Ó The New
York Review of Books. Vol. LIII:12, July 13, 2006. pp. 12-16.
ÒThe most effective action,
as I have indicated, would be a slowly increasing carbon tax, which would be
revenue neutral or would cover a portion of the costs of mitigating climate
change.Ó
( page, 14.)
return to Home page
GENEVA, 25 NOVEMBER 2008 (WMO) Ð
Levels of climate-warming greenhouse gases continue to increase in the atmosphere. In 2007, global concentrations of carbon dioxide again reached the highest levels ever recorded.
These latest numbers, published today in the World Meteorological OrganizationÕs (WMO) 2007 Greenhouse Gas Bulletin, continue the trend of rising emissions of greenhouse gases since the Industrial Revolution.
Human activities, such as fossil fuel burning and agriculture, are major emitters of the gases, which scientists widely recognize as drivers of global warming and climate change.
After water vapour, the four most prevalent greenhouse gases in the atmosphere are carbon dioxide, methane, nitrous oxide and chloro fluoro carbons.
The WMO Global Atmosphere Watch (GAW) coordinates the measurement of these gases in the atmosphere through a network of observatories located in more than 65 countries.
The latest numbers show that carbon dioxide reached 383.1 parts per million (ppm), an increase of 0.5 percent from 2006.
Concentrations of nitrous oxide also reached record highs in 2007, up 0.25 per cent from the year before, while
methane increased 0.34 per cent, exceeding the highest value so far, which was recorded in 2003.
Using the NOAA Annual greenhouse gas index, the total warming effect of all long-lived greenhouse gases was calculated to have increased by 1.06 per cent from the previous year and by 24.2 per cent since 1990.
