Climate Change & Global Warming

The annual average concentration of carbon dioxide (CO2) in the atmosphere stood at 395.3 parts per million (ppm) in 2013—a 27 percent increase compared to conditions before the Industrial Revolution. On May 9, 2013, the daily average concentration of CO2 surpassed 400 ppm for the first time at the Mauna Loa Observatory in Hawaii.

September 2009

  • Richard Feely discusses new findings about how increased carbon dioxide in the atmosphere is making the oceans more acidic, and how that will affect ocean ecosystems and the marine animals that inhabit them.
     

  • Richard Feely discusses new findings about how increased carbon dioxide in the atmosphere is making the oceans more acidic, and how that will affect ocean ecosystems and the marine animals that inhabit them.
     

  •  The Sun is the main source of power for the Earth's climate machine. Space-based measurements, begun in 1978, indicate Earth receives an average of 1,361 W/m<sup>2</sup> of incoming sunlight, and the amount varies by about one-tenth of a percent over the course of the 11-year solar cycle.