'Charles David Keeling was a stickler for precision. The measurements of CO2 he began in the 1950s were an order of magnitude more accurate than previous measurements. In recognizing the value of a continuous record, and obtaining it, he brought a clarity to the problem that altered our perceptions about global change and the degree to which the Earth can absorb the human assault.'
Dr. James Hansen
Rewards and Penalties for Monitoring the Earth
Charles David Keeling, 1998
Images courtesy of the Scripps Institution of Oceanography
Understanding the Keeling Curve
Credit: Climate Communication