![Carbon dioxide (CO2) concentrations in Earth’s atmosphere plotted over the past 1,000 …[Credits : From W.M. Post, F. Chavez, P.J. Mulholland, J. Pastor, T.H. Peng, K. Prentice, and T. Webb III, “Climatic Feedbacks in the Global Carbon Cycle,” in David A. Dunnette and Robert J. O’Brien (eds.), The Science of Global Change: The Impact of Human Activities on the Environment, American Chemical Society Symposium Series 483, 1992]](http://media-2.web.britannica.com/eb-media/39/6539-004-A08B053E.gif)
Carbon dioxide (CO2) concentrations in Earth’s atmosphere plotted over the past 1,000 years. A rise in the CO2 level began after 1800 and has accelerated ever since. Values before the last half of the 20th century (Antarctic and Siple) are derived from analysis of samples of atmosphere trapped in polar ice. Later values (Mauna Loa) are direct atmospheric measurements.
Link to this article and share the full text with the readers of your Web site or blog-post.
If you think a reference to this article on "" will enhance your Web site,
blog-post, or any other web-content, then feel free to link to this article,
and your readers will gain full access to the full article, even if they do not subscribe to our service.
You may want to use the HTML code fragment provided below.
We welcome your comments. Any revisions or updates suggested for this article will be reviewed by our editorial staff. Contact us here.
Regular users of Britannica may notice that this comments feature is less robust than in the past. This is only temporary, while we make the transition to a dramatically new and richer site. The functionality of the system will be restored soon.