NOAA's Mauna Loa Observatory, from NOAA At the Ends of the Earth Collection, 1982 NOAA photo by Commander John Bortniak
John Adams observed, and Ronald Reagan was fond of quoting, “Facts are stubborn things . . .”
Here are the facts on atmospheric carbon dioxide (CO2):
Mauna Loa Observatory, Scripps Institution of Oceanography, UCSD (University of Calfornia-San Diego); CO2 concentrations in parts per million (ppm)
As described at the Scripps Institution of Oceanography site:
Description:
Monthly average atmospheric carbon dioxide concentration versus time at Mauna Loa Observatory, Hawaii (20°N, 156°W) where CO2 concentration is in parts per million in the mole fraction (p.p.m.). The curve is a fit to the data based on a stiff spline plus a 4 harmonic fit to the seasonal cycle with a linear gain factor.Data from Scripps CO2 Program.
For perspective, here’s a chart from Scripps that shows why there is concern over current levels of CO2:
CO2 over the past 420,000 years - Scripps Institution of Oceanography
Resources, More:
- More graphs from Mauna Loa Observatory, with slightly different assumptions, here
- Scripps CO2 Program home (“Home of the Keeling Curve”)
- CO2 data from six different observing stations, on one chart
- “Keeling Curve Lessons”
- FAQ at the CO2 Program:
- How do we know that CO2 is increasing in the atmosphere?
- How fast is CO2 increasing in the atmosphere and is this changing?
- How do we know that the CO2 increase is caused by human activities?
- Isn’t the Mauna Loa record influenced by CO2 emitted by the volcano?
- How much has atmospheric CO2 increased since the industrial and agricultural revolutions?
- What are stable isotopes in atmospheric CO2 and why are these measured as well as its concentration?
Posted by Ed Darrell 
Millard Fillmore's Bathtub 