Linear and nonlinear effects of dominant drivers on the trends in global and regional land carbon uptake: 1959 to 2013. Issue 4 (25th February 2016)

• Record Type: Journal Article
• Authors: Zhang, Xuanze; Rayner, Peter J.; Wang, Ying‐Ping; Silver, Jeremy D.; Lu, Xingjie; Pak, Bernard; Zheng, Xiaogu
• Is Part Of: Geophysical research letters. Volume 43:Issue 4(2016)
• Page Start: 1607
• Page End: 1614
• Publication Date: 2016-02-25
• Subjects: terrestrial carbon cycle -- climate drivers -- nonlinear interaction -- CABLE -- land carbon sink -- trend; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2015GL067162
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Changes in atmospheric CO2 levels, surface temperature, or precipitation have been identified to have significantly contributed to the estimated increase in the terrestrial carbon uptake rate over the last few decades; however, those analyses did not consider the interactions. Using the Australian community land surface model (Community Atmosphere Biosphere Land Exchange), we performed factorial experiments to quantify the importance of external drivers (climate drivers and atmospheric CO2 ) and their interactions on annual terrestrial carbon uptake ( F L ), excluding land use change and fires, from 1959 to 2013. Our model simulations show a trend of 0.025 ± 0.015 Pg C yr −2 (or ~1.5% yr −1 ) in global F L for 1959–2013, which is largely attributed to the positive influences of the increased atmospheric CO2 (0.050 ± 0.001 Pg C yr −2 ) and negative influences of changes in climate (−0.026 ± 0.014 Pg C yr −2 ). Globally, the contribution of the nonlinear effects of dominant drivers to the simulated trend in F L is small (<10%) but can be significant regionally (>35%), particularly in the boreal forests and semiarid regions. The interactions between temperature and CO2 or temperature and precipitation can dominate the simulated trend in parts of Europe, southeastern North America, southern China, and some semiarid regions. This modeling result suggests that the effects of nonlinear interactions of drivers on the trend of land carbon uptake should be considered in future studies. Key Points: Attributing historical trends in land carbon uptake Climate derivers affecting land carbon uptake nonlinearly Interaction between temperature and CO2 largely contributing the boreal forests