The biggest-ever annual rise in atmospheric CO2 levels has been recorded by a Hawaii-based atmospheric monitoring station.

The Mauna Loa Observatory in Hawaii has been recording atmospheric CO2 levels since 1958. Based on continuous measurements taken at the observatory, a graph is produced, known as the Keeling Curve. It depicts the annual variation and overall accumulation of CO2 in the atmosphere.

Last year, the Keeling Curve revealed that the level of CO2 in the atmosphere increased by 3.58 parts per million (ppm) to 427ppm – the biggest leap since records began there almost 70 years ago. This exceeded the Met Office’s prediction of 2.84±0.54 ppm.

This predictive overshooting is concerning: the Intergovernmental Panel on Climate Change (IPCC) calculates that if global warming is to be limited to 1.5°C, the build-up of CO₂ in the air needs to be slowing to 1.8ppm a year.

The reason for the huge surge in CO2 levels in 2024 is down to a number of factors. These include CO2 emissions from...