PES » Global Warming » Modern Atmospheric Concentrations of Carbon Dioxide
	Practice Questions Movie Transcript The concentration of carbon dioxide in the atmosphere is increasing. This movie will help you describe how the concentration of carbon dioxide in the atmosphere has changed over the last 100 years. At the start of the Industrial Revolution, the concentration of carbon dioxide in the atmosphere was about 280 parts per million by volume. As industrialization spread, the consumption of fossil fuel, that is oil, gas and coal, rapidly increased. By the late 1940šs the atmospheric carbon dioxide concentration had risen to 300 parts per million. After World War II, automobiles became the favored mode of transportation in the United States and industrialization grew rapidly across the globe. Today, the concentration of carbon dioxide in the atmosphere has risen to 360 parts per million. This increase is alarming because the rate at which carbon dioxide is being released into the atmosphere continues to steadily increase. Human activities currently release about 6.5 billion tons of carbon into the air per year. Each year, as all nations intensify industrial development, this amount grows. The atmospheric carbon dioxide concentration is now higher than it has been in the last 100 thousand years. At current rates, atmospheric carbon dioxide is expected to reach twice the pre- industrial level, 560 parts per million, within the next 100 years. In summary, the pre-industrial level of carbon dioxide in the atmosphere had been consistently less than 300 parts per million for the past 100 thousand years. Since the Industrial Revolution, the level has risen to 360 parts per million and is expected to reach 560 parts per million within the next 100 years.		forward: Modern Global Temperature back: Human Activities and Carbon Dioxide browse: Table of Contents
			forward: Modern Global Temperature back: Human Activities and Carbon Dioxide

	Subscribe to the Earth Observatory About the Earth Observatory Contact Us Privacy Policy and Important Notices Responsible NASA Official: Lorraine A. Remer Webmaster: Goran Halusa We're a part of the Science Mission Directorate