Report from the President (Land Lines Article)

Climate Change and Urban Development

Author(s): Ingram, Gregory K.
Publication Date: October 2009

1 pages; Inventory ID LLA091001; English


Message from the President	452 KB

Article

Accumulating evidence indicates that increasing concentrations of greenhouse gases, primarily carbon dioxide, are raising average temperatures, acidifying and raising the level of oceans, and accelerating natural rates of carbon dioxide emissions. Uncertainties abound, but the carbon dioxide concentration in the earth’s atmosphere has risen by 31 percent since 1850 and now exceeds levels experienced over the past 420,000 years. Recent estimates from North America (for 2003) indicate that its anthropogenic carbon dioxide emissions (mainly from burning fossil fuels) were about 1856 million metric tons per year, or about a quarter of all such global emissions.