Monitoring global carbon emissions in 2021

Abstract

Following record-level declines in 2020, near-real-time data indicate that global CO₂ emissions rebounded by 4.8% in 2021, reaching 34.9 GtCO₂. These 2021 emissions consumed 8.7% of the remaining carbon budget for limiting anthropogenic warming to 1.5 °C, which if current trajectories continue, might be used up in 9.5 years at 67% likelihood.

Keywords: Climate-change mitigation; Projection and prediction.

Fig. 1. Global CO₂ and CH₄ emission trends.

Temporal evolution of historical CO₂ emissions (navy; including emissions from fossil fuel combustion and the process of cement production), near-real-time CO₂ emissions^, (red), projected CO₂ emission mitigation pathways (dark blue and aqua), and historical fossil CH₄ emissions^] (light blue; 1970–2018 data from EDGARv6.0, scaled to 2021 with IEA data). Solid/dashed lines and shading represent the median and range, respectively. The inset depicts daily near-real-time CO₂ data over 2019 to 2021, and the corresponding year-on-year changes in annual CO₂ emissions. Current emission trends will use up the allowed future emissions for limiting anthropogenic warming to 1.5 °C (the remaining carbon budgets) within 10 years.