Back to Search Start Over

State of the science in reconciling top-down and bottom-up approaches for terrestrial CO2 budget

Authors :
Kondo, Masayuki
Patra, Prabir P.K.
Sitch, Stephen
Friedlingstein, Pierre
Poulter, Benjamin
Chevallier, Frédéric
Ciais, Phillipe
Canadell, Josep J.G.
Bastos, Ana
Lauerwald, Ronny
Calle, Leonardo
Ichii, Kazuhito
Anthoni, Peter
Arneth, Almut
Haverd, Vanessa
Jain, Atul
Kato, Etsushi
Kautz, Markus
Law, Rachel R.M.
Lienert, Sebastian
Lombardozzi, Danica
Maki, Takashi
Nakamura, Takashi
Peylin, Philippe
Rödenbeck, Christian
Zhuravlev, Ruslan
Saeki, Tazu
Tian, Hanqin
Zhu, Dan
Ziehn, Tilo
Kondo, Masayuki
Patra, Prabir P.K.
Sitch, Stephen
Friedlingstein, Pierre
Poulter, Benjamin
Chevallier, Frédéric
Ciais, Phillipe
Canadell, Josep J.G.
Bastos, Ana
Lauerwald, Ronny
Calle, Leonardo
Ichii, Kazuhito
Anthoni, Peter
Arneth, Almut
Haverd, Vanessa
Jain, Atul
Kato, Etsushi
Kautz, Markus
Law, Rachel R.M.
Lienert, Sebastian
Lombardozzi, Danica
Maki, Takashi
Nakamura, Takashi
Peylin, Philippe
Rödenbeck, Christian
Zhuravlev, Ruslan
Saeki, Tazu
Tian, Hanqin
Zhu, Dan
Ziehn, Tilo
Source :
Global change biology
Publication Year :
2019

Abstract

Robust estimates of CO2 budget, CO2 exchanged between the atmosphere and terrestrial biosphere, are necessary to better understand the role of the terrestrial biosphere in mitigating anthropogenic CO2 emissions. Over the past decade, this field of research has advanced through understanding of the differences and similarities of two fundamentally different approaches: “top-down” atmospheric inversions and “bottom-up” biosphere models. Since the first studies were undertaken, these approaches have shown an increasing level of agreement, but disagreements in some regions still persist, in part because they do not estimate the same quantity of atmosphere–biosphere CO2 exchange. Here, we conducted a thorough comparison of CO2 budgets at multiple scales and from multiple methods to assess the current state of the science in estimating CO2 budgets. Our set of atmospheric inversions and biosphere models, which were adjusted for a consistent flux definition, showed a high level of agreement for global and hemispheric CO2 budgets in the 2000s. Regionally, improved agreement in CO2 budgets was notable for North America and Southeast Asia. However, large gaps between the two methods remained in East Asia and South America. In other regions, Europe, boreal Asia, Africa, South Asia, and Oceania, it was difficult to determine whether those regions act as a net sink or source because of the large spread in estimates from atmospheric inversions. These results highlight two research directions to improve the robustness of CO2 budgets: (a) to increase representation of processes in biosphere models that could contribute to fill the budget gaps, such as forest regrowth and forest degradation; and (b) to reduce sink–source compensation between regions (dipoles) in atmospheric inversion so that their estimates become more comparable. Advancements on both research areas will increase the level of agreement between the top-down and bottom-up approaches and yield more robust knowledge of r<br />SCOPUS: ar.j<br />DecretOANoAutActif<br />info:eu-repo/semantics/published

Details

Database :
OAIster
Journal :
Global change biology
Notes :
No full-text files, English
Publication Type :
Electronic Resource
Accession number :
edsoai.on1335123317
Document Type :
Electronic Resource