Fact Check: "Carbon dioxide levels in the atmosphere were 313 ppm in 1958."
What We Know
The claim that carbon dioxide levels in the atmosphere were 313 parts per million (ppm) in 1958 is supported by multiple credible sources. The modern record of atmospheric carbon dioxide began with continuous measurements taken at the Mauna Loa Observatory in Hawaii, starting in March 1958. The first recorded measurement at this site indicated a CO2 concentration of 313 ppm (Keeling Curve, History.com). Additionally, a report by NOAA confirms that by the time continuous observations began, the atmospheric CO2 was already at 315 ppm, indicating that the levels were indeed around 313 ppm during that period (NOAA Climate.gov).
Analysis
The evidence supporting the claim is robust and comes from well-established scientific measurements. The Mauna Loa Observatory is recognized as a premier site for atmospheric monitoring due to its remote location and lack of local contamination, which enhances the reliability of the data collected there (Keeling Curve). The Keeling Curve, named after scientist Charles David Keeling, is widely regarded as one of the most significant scientific contributions to understanding climate change, as it provided the first clear evidence of the rapid increase in atmospheric CO2 levels (Keeling Curve, History.com.
While some sources may report slightly varying figures (e.g., 315 ppm), the consensus remains that the initial measurements in 1958 were around 313 ppm, which aligns with the claim. The data from the Keeling Curve and corroborating reports from NOAA and other reputable institutions lend credibility to this figure. The consistency across these sources indicates a high level of reliability, as they are based on systematic and continuous scientific observations.
Conclusion
Verdict: True
The claim that carbon dioxide levels in the atmosphere were 313 ppm in 1958 is accurate. This figure is supported by multiple credible sources, including the initial measurements taken at the Mauna Loa Observatory, which are widely recognized in climate science. The evidence is consistent and reliable, confirming that the atmospheric CO2 concentration was indeed around this level during that time.
