349.37 ppm CO₂
Born when atmospheric CO₂ at Mauna Loa was 349.37 ppm.
Most recent measurement: 431.12 ppm (April 2026) — about 82 ppm higher than when I was born.
Source: NOAA Global Monitoring Laboratory, Mauna Loa monthly mean CO₂. Pre-1974 measurements by C. David Keeling, Scripps Institution of Oceanography. Data fetched and embedded at build time.
Further reading: NOAA — CO₂ trends, NASA — Carbon Dioxide, Wikipedia — CO₂ in the atmosphere.