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Carbon Dioxide, Climate Change, and the Boston Region MPO: A Discussion Paper

Trends in Atmospheric Concentrations and Anthropogenic Emissions of CO2

Figure 1 is a line graph showing the trends in atmospheric concentrations and anthropogenic emissions of carbon dioxide.

This chart shows the changes in Atmospheric Concentrations of Carbon Dioxide and Anthropogenic Emissions of Carbon Dioxide between 1750 and 2000. The data for Atmospheric Concentrations begins in 1750 at a level of almost 280 parts per million by volume (ppmv). It slowly increases to about 290 ppmv in 1900 and to about 310 ppmv in 1950, and then begins to rapidly increase up to 340 ppmv in 1975 and 360 ppmv in 2000. The line at this part of the graph shows a very steep curve, indicating that the trend will be rapid increase of atmospheric concentrations. The second line shows Anthropogenic Emissions, but these data began only in 1850. The 1850 emission levels were at zero, yet climbed to 1,500 million metric tons of carbon in 1950. The line then takes a very steep, almost vertical slope, increasing to almost 7,000 million metric tons of carbon in 2000. Although these two lines on the chart are different measurements, the chart illustrates the that while both carbon dioxide concentrations and human induced carbon dioxide emission have increased, the sudden increase in human induced carbon emissions changes the shallowly increasing carbon dioxide concentrations to drastically increasing concentration levels.

Source: Oak Ridge National Laboratory, Carbon Dioxide Information Analysis Center, http://cdiac.ornl.gov/

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Updated: 03/26/2013
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