Charles David Keeling began taking daily measurements of the Carbon Dioxide concentration in the atmosphere at the top of Mauna Loa in Hawaii in 1958 (Monroe). This program is still around; however, there are more locations around the world where data is collected (Monroe). He began this work while doing his doctoral studies in California. He noticed that there was more CO2 at night in Big Sur, and in the afternoons, there was almost always 310ppm (Monroe). He took measurements of atmospheric CO2 in multiple locations, and all found a concentration of 310 ppm until he went to Mauna Loa and found a concentration of 313 ppm (Monroe). The concentration continued to rise until May, when there began to be a decrease in atmospheric CO2 and then an increase back in October (Monroe). Keeling began to realize that the concentration of atmospheric CO2 was reliant on “seasonal changes of growth and decay” (Kennedy, 1). The data collected is now known as the Keeling Curve and is heavily used to monitor our atmospheric CO2.

Kennedy, Caitlyn. “Carbon Dioxide: Earth’s Hottest Topic Is Just Warming Up”. NOAA Climate, 2009, https://www.climate.gov/news-features/understanding-climate/carbon-dioxide-earths-hottest-topic-just-warming.

Monroe, Rob. “The History Of The Keeling Curve”. The Keeling Curve, 2022, https://keelingcurve.ucsd.edu/2013/04/03/the-history-of-the-keeling-curve/.