CO2 from Human Action
Human (anthropogenic) activity, including the use of fossil fuel, releases greenhouse gases
to the atmosphere.
Over 100 years ago, Svante Arrhenius, a Swedish scientist and Nobel Prize winner, postulated that
the emissions of anthropogenic CO2
from fossil fuel combustion could eventually have a
profound effect on the heat budget of the atmosphere. In 1904, Arrhenius stated that "the slight
percentage of carbonic acid [combination of carbon and oxygen or CO2
and water vapor] in
the atmosphere may, by the advances of industry, be changed to a noticeable degree in the course of
a few centuries." 1
Beginning in the 1850s, the use of fossil fuels became more common as the Industrial Revolution
gained momentum in Europe and North America. Since that time, humans have used the energy in fossil
fuels to build a dynamic global economy and an improved quality of life. Over this same period, human
activity has added over 300 billion tons of anthropogenic carbon to the
global carbon cycle
. Since the 1850s, CO2
levels in the atmosphere have increased
nearly 30%, and the concentrations of other greenhouse gases like methane (more than doubled) and
nitrous oxide (up by about 15%) have also increased.2
Humans are currently adding over
9 billion tons of anthropogenic carbon
to the atmosphere each year, with nearly 2 billion tons
coming from the United States.3
Most of the anthropogenic carbon emissions would result
from the combustion of fossil fuels in transportation, electrical generation, and heating and
cooling for buildings.2
Reducing the emissions of anthropogenic CO2
and other anthropogenic emissions of carbon-based
greenhouse gases is a concrete step that humans can take to address the rising levels of CO2
other greenhouse gases in the atmosphere.4
- earthobservatory.nasa.gov/Library/Giants/Arrhenius (accessed August 2005).
- www.eia.doe.gov/oiaf/1605/ggccebro/chapter1.html (accessed November 2004).
- Carbon Dioxide Information Analysis Center, http://cdiac.ornl.gov/trends/emis/meth_reg.html
(accessed November 2010).
- Pacala, S., and Sokolow, R., 2004, Stabilization wedges - solving the climate problem for the next 50 years with current technologies: Science, v. 305, p. 968-972.
In 2000, the largest emitter of CO2 was the United States. Western Europe,
the former USSR and Eastern Europe and China each produce about half of the amount of
CO2 produced in the United States!
Source: Marian Koshland Science Museum of the National Academy of Sciences