The Human Impacts Database

A collection of useful numbers for quantifying the impacts of the human presence on Earth.

Atmospheric CO2 concentration

Atmospheric & Biogeochemical CyclesCarbon Dioxide

This quantity comes from a time series measurement and the most recent value (1964-2023) is reported.


This is equivalent to...

≈ 4.20 × 10-4 mol CO2 mol-1 air

≈ 6.38 × 10-4 kg CO2 kg-1 air

≈ 3.29 × 1015 kg CO2

HuID: 81043
Relevant Year(s): 1964-2023
Summary: The present carbon dioxide (CO2) concentration in the atmosphere as measured at the Mauna Loa Observatory. Temporal variations in the CO2 concentration can be seen as periodic oscillations corresponding to seasonal changes. The carbon dioxide data on Mauna Loa constitute the longest record of direct measurements of CO2 in the atmosphere. They were started by C. David Keeling of the Scripps Institution of Oceanography in March of 1958 at a facility of the National Oceanic and Atmospheric Administration.
Method: Uncertainty in measurements is not reported in original source, and it is assumed lower than the monthly variability. The Mauna Loa data are being obtained at an altitude of 3400 m in the northern subtropics, and may not be the same as the globally averaged CO2 concentration at the surface. The mass of CO2 is obtained from the concentration using the molar mass of CO2, 44 g mol-1; the molar mass of air, 29 g mol-1; and the mass of the atmosphere, 5.15 × 1018 kg.
Source: Scripps CO2 Program Primary Mauna Loa CO2 Record. (2021)
Dataset: Monthly atmospheric CO2 measurements from Mauna Loa Observatory (monthly_co2_data_processed.csv)
regional resolution
Original Data License: Mauna Loa Free Use Policy
Added By: ilopezgo