Historical carbon dioxide emissions caused by land-use changes are possibly larger than assumed - CEA - Université Paris-Saclay Accéder directement au contenu
Article Dans Une Revue Nature Geoscience Année : 2017

Historical carbon dioxide emissions caused by land-use changes are possibly larger than assumed

Almut Arneth
Julia Pongratz
P. Friedlingstein
M. Lindeskog
  • Fonction : Auteur
E. Robertson
  • Fonction : Auteur
S. Zaehle

Résumé

The terrestrial biosphere absorbs about 20% of fossil-fuel CO2 emissions. The overall magnitude of this sink is constrained by the difference between emissions, the rate of increase in atmospheric CO2 concentrations, and the ocean sink. However, the land sink is actually composed of two largely counteracting fluxes that are poorly quantified: fluxes from land-use change and CO2 uptake by terrestrial ecosystems. Dynamic global vegetation model simulations suggest that CO2 emissions from land-use change have been substantially underestimated because processes such as tree harvesting and land clearing from shifting cultivation have not been considered. As the overall terrestrial sink is constrained, a larger net flux as a result of land-use change implies that terrestrial uptake of CO2 is also larger, and that terrestrial ecosystems might have greater potential to sequester carbon in the future. Consequently, reforestation projects and efforts to avoid further deforestation could represent important mitigation pathways, with co-benefits for biodiversity. It is unclear whether a larger land carbon sink can be reconciled with our current understanding of terrestrial carbon cycling. Our possible underestimation of the historical residual terrestrial carbon sink adds further uncertainty to our capacity to predict the future of terrestrial carbon uptake and losses.
Fichier principal
Vignette du fichier
a3.pdf (892.27 Ko) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Loading...

Dates et versions

hal-01681571 , version 1 (14-05-2018)

Identifiants

Citer

Almut Arneth, Stephen Sitch, Julia Pongratz, B. D. Stocker, Philippe Ciais, et al.. Historical carbon dioxide emissions caused by land-use changes are possibly larger than assumed. Nature Geoscience, 2017, 10 (2), pp.79-84. ⟨10.1038/NGEO2882⟩. ⟨hal-01681571⟩
1327 Consultations
626 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More