The Met Office predicts that annual average CO2 concentration at Mauna Loa Observatory, Hawaii, will be 2.29 ± 0.55 parts per million (ppm) higher in 2021 than in 2020.

This rise is driven by emissions from fossil fuel burning and deforestation, but will be slightly smaller than usual due to a temporary strengthening of natural carbon sinks. Weather patterns linked to the current La Niña event are expected to promote a temporary burst of growth in tropical forests that soak up some of humanity’s emissions. 

Read more at the metoffice website.