The Keeling Curve
Continuous measurement from a Hawaiian volcano shows carbon dioxide rising every year.
- When
- Known to
- ± 1 year
- Era
- Contemporary, Holocene
Charles Keeling begins measuring atmospheric carbon dioxide at Mauna Loa in 1958 and produces the first unambiguous evidence that it is accumulating — an annual sawtooth from Northern Hemisphere plant growth superimposed on a relentless upward trend. It has run continuously ever since, from 315 parts per million to over 420. It is among the most consequential datasets ever collected, and its funding was repeatedly threatened.