What does it look like now? See this graphic from the New York Times:
New York Times, May 11, 2013
More:
- Keeling Curve a mainstay of climate science (utsandiego.com)
- Greenhouse Gas to Reach 3-Million-Year High (livescience.com)
- Atmospheric Carbon Dioxide Breaks 3-Million-Year Record (livescience.com)
- Editorial: Plenty of oil fueling the race to climate disaster (stltoday.com)
- Climate Change Pushes Carbon Dioxide to Worrisome Milestone (boiseweekly.com)
- The Last Time CO2 Was This High, Humans Didn’t Exist (climatecentral.org)
- Climate Milestone: Earth’s CO2 Level Nears 400 ppm (news.nationalgeographic.com)
- Carbon dioxide level crosses milestone at Hawaii site (reuters.com)
- Climate Change: Looking at 400 ppm and Beyond (theenergycollective.com)
- The Last Time CO2 Was This High, Humans Didn’t Exist (yubanet.com)
- Keeling Curve lessons from the Scripps Institute
Posted by Ed Darrell 
Millard Fillmore's Bathtub 