Historical warming reduced due to enhanced land carbon uptake

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 110; no. 42; pp. 16730 - 16735
• Main Authors: Shevliakova, Elena, Stouffer, Ronald J., Malyshev, Sergey, Krasting, John P., Hurtt, George C., Pacala, Stephen W.
• Format: Journal Article
• Language: English
• Published: Washington, DC National Academy of Sciences 15.10.2013; NATIONAL ACADEMY OF SCIENCES; National Acad Sciences
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Atmosphere; Atmospheric models; Atmospherics; Biological and medical sciences; Biological Sciences; Carbon; Carbon Dioxide; Carbon sinks; Climate change; Climate models; Emissions; Fertilization; Fluid dynamics; Fundamental and applied biological sciences. Psychology; Global Warming; Land; Land use; Models, Theoretical; Physical Sciences; Plants - metabolism; Synecology; Terrestrial ecosystems; Vegetation; Terrestrial environment; Warming; Vegetation effect; Carbon; Case history; Modeling; Carbon sequestration; Land use; Earth planet; Dynamical climatology; Carbon cycle; Climate change; Absorption; carbon sink; Greenhouse gas; earth system modeling; climate change
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.1314047110

Previous studies have demonstrated the importance of enhanced vegetation growth under future elevated atmospheric CO ₂ for 21st century climate warming. Surprisingly no study has completed an analogous assessment for the historical period, during which emissions of greenhouse gases increased rapidly and land-use changes (LUC) dramatically altered terrestrial carbon sources and sinks. Using the Geophysical Fluid Dynamics Laboratory comprehensive Earth System Model ESM2G and a reconstruction of the LUC, we estimate that enhanced vegetation growth has lowered the historical atmospheric CO ₂ concentration by 85 ppm, avoiding an additional 0.31 ± 0.06 °C warming. We demonstrate that without enhanced vegetation growth the total residual terrestrial carbon flux (i.e., the net land flux minus LUC flux) would be a source of 65–82 Gt of carbon (GtC) to atmosphere instead of the historical residual carbon sink of 186–192 GtC, a carbon saving of 251–274 GtC.