What can the Glasgow Declaration on Forests bring to global emission reduction?

Commentary; International audience; The Glasgow Declaration on Forests signed at the recent UN Climate Change Conference (COP 26) committed to halting forest loss by 2030. 141 countries and regions, collectively covering over 90% of global forest, endorsed this declaration. Avoiding forest loss can generally contribute to climate change mitigation; however, the impacts of the declaration on global carbon dioxide (CO$_2$) emission reduction are still unclear. Here we show that the Glasgow Declaration, if implemented fully and in a timely fashion, could reduce 123 Gt CO$_2$ of emission from 2021 to 2050. This study also highlights that any delays in implementing the declaration would decrease the avoided emission. Although the Glasgow Declaration is a milestone for mitigating climate change, the more ambitious afforestation plan is urgently needed to keep the global temperature rise to below 1.5°C relative to pre-industrial levels.