Daily CO2 Readings

Daily CO2 readings are updated here automatically with the latest atmospheric CO2 readings available from the Mauna Loa Observatory in Hawaii.

Data sources: March 1958 to April 1974: Scripps Institution of Oceanography, May 1974 to present day: Dr. Pieter Tans, NOAA/GML

Last update: 2:35:04 AM on Apr. 15, 2024, Hawaii local time (UTC -10)

Latest daily averages (last 10 days)

Latest One year ago Change from previous year
Date Reading Date Reading
Apr. 14, 2024 425.27 ppm Apr. 15, 2023 424.30 ppm 0.97 ppm increase (0.23 %)
Apr. 13, 2024 425.70 ppm Apr. 14, 2023 422.97 ppm 2.73 ppm increase (0.65 %)
Apr. 12, 2024 424.80 ppm Apr. 13, 2023 Unavailable n/a
Apr. 11, 2024 425.41 ppm Apr. 12, 2023 423.23 ppm 2.18 ppm increase (0.52 %)
Apr. 10, 2024 427.35 ppm Apr. 11, 2023 423.06 ppm 4.29 ppm increase (1.01 %)
Apr. 9, 2024 Unavailable Apr. 10, 2023 422.29 ppm n/a
Apr. 8, 2024 425.67 ppm Apr. 9, 2023 421.70 ppm 3.97 ppm increase (0.94 %)
Apr. 7, 2024 426.25 ppm Apr. 8, 2023 422.04 ppm 4.21 ppm increase (1.00 %)
Apr. 6, 2024 425.99 ppm Apr. 7, 2023 422.37 ppm 3.62 ppm increase (0.86 %)
Apr. 5, 2024 426.71 ppm Apr. 6, 2023 423.01 ppm 3.70 ppm increase (0.87 %)