Pre-Industrial Levels of CO2

Carbon dioxide levels have increased since the Industrial Revolution.

Since the beginning of the Industrial Revolution, which is said by historians to have started around 1760, levels of atmospheric carbon dioxide have increased as a result of human activities, including the burning of fossil fuels, and cutting down of forests. The concentrations of CO2 in the atmosphere have increased 40 percent since the start of the Industrial Revolution, according to the British Broadcasting Corp.

Background

The CO2 in the atmosphere comes from some natural sources, such as volcanoes erupting and plant decay. However, the Industrial Revolution brought widespread global environmental changes, including the burning of coal, oil and gas for industrial and consumer purposes. According to the National Oceanic and Atmospheric Administration, some 7 billion tons of carbon in CO2 form is released into the atmosphere annually.

Increased Levels

According to the NOAA, scientific measurements of the carbon dioxide in ice cores, or cylinders of ice, showed that the CO2 level prior to the Industrial Revolution was 278 parts per million. In addition, the levels did not change more than 7 ppm between 1000 and 1800 A.D. By comparison, in 2004, the atmospheric CO2 levels were 378 ppm, an increase of 36 percent. The levels were 315 ppm in 1958.

Deforestation

The oceans, trees, plants and soil absorb about half of the carbon produced by humans, while the rest goes into the atmosphere. The clearing of forests means less of this carbon can be absorbed.

References

• National Oceanic and Admospheric Administration News: After two large gains, rate of atmospheric CO2 increase returns to average, NOAA reports; March 2005.
• U.S. Environmental Protection Agency: Carbon Dioxide.
• BBC Weather Centre: Climate Change; July 2009.