Forest carbon offsets are failing

Conserving tropical forests is of utmost importance for the future of humanity and biodiversity. Changes in land use, mostly deforestation in the tropics, emit 5 billion metric tons of carbon dioxide annually—second only to fossil fuel use, which emits 35 billion tons (1). Reducing emissions to net zero is necessary to stabilize global temperatures (2). One controversial approach to tackle fossil-fuel emissions from private companies, individuals, and governments has been to “offset” them by investing in projects to either stop emissions that would have otherwise occurred, such as by reducing deforestation, or by investing in carbon uptake projects, such as forest restoration. On page 873 of this issue, West et al. (3) show that offsetting through paying projects to reduce emissions by conserving tropical forests is not reducing deforestation as claimed and is worsening climate change.