Emissions were not always the mainstay of CO2 monitoring. When records first began at Mauna Loa, US, in 1957, they aimed to track the concentration of atmospheric CO2 as it rose and fell with Earth’s seasons and orbital cycles.
The choice of location, 4000km from the nearest global industrial hub (and the nearest gypsum wallboard plant) in Los Angeles, however, was telling. CO2 had been recognised as a product of burning fuels since the late 18th Century and as a greenhouse gas since 1859. Now, data from Mauna Loa substantiated the climactically consequential matter of industrial emissions: atmospheric CO2 was increasing, by 35% between 1957 and 2025.


