Carbon Dioxide (CO2) is the most widely known "greenhouse gas". Over the 20th century, global atmospheric CO2 levels have steadily risen from just below 300 parts per million (ppm) in the early 1900's to current levels of approximately 380ppm. General consensus within the scientific community ascribes this increase to the burning of fossil fuels (coal, oil, and natural gas). In 2000, the world emitted some 24 billion metric tons of CO2 from the burning of fossil fuels. This means roughly 3.9 metric tons were emitted on a per capita basis worldwide. However, the disparity between the developed world and the developing world is substantial; per capita, people residing in developed countries emitted 11.2 metric tons, nearly 6 times their counterparts in the developing world where the per capita average equaled 1.9 metric tons.
At present, the United States accounts for around 20-24% of all CO2 emissions, although the United States population constitutes fewer than 5% of the world total. China, the second largest emitter of CO2, releases approximately 15% of total CO2 emissions and accounts for roughly 21% of the world's population. It is expected that as China's population continues to increase and the country continues to industrialize, China will overtake the United States as the top emitter of CO2 within the next twenty-five years (Baumert et al., 2005). China's industrialization has also led to a rise in emissions of other greenhouse gases as well; SO2 emissions increased by 35% between 1990 and 1995 (SO2 is a precursor to acid rain and is the main emissions by-product of coal burning).
Selected relevant content available on EarthTrends and at WRI:
WRI Publications and Websites:
Baumert, K.A., T. Herzog, and J. Pershing. 2005. Navigating the Numbers: Greenhouse Gas Data and International Climate Policy. World Resources Institute: Washington, D.C.
Climate Analysis Indicators Tool 3.0
Variables:
CO2 : Total emissions (source: WRI)
Global gas concentrations: CO2
CO2 : Emissions per capita (source: WRI)
Data Tables:
Carbon Dioxide Emissions by Economic Sector 2005
Carbon Dioxide Emissions by Source 2005
Features:
Will Developing Countries' Carbon Emissions Swamp Global Emissions Reduction Efforts?
Maps:
Carbon Emissions Per Capita, 1999
Total CO2 Emissions, Excluding Land Use Change, 2000
