Elevated CO2 concentrations increase photosynthesis and, potentially, net ecosystem production (NEP), meaning a greater CO2 uptake. Climate, nutrients and ecosystem structure, however, influence the effect of increasing CO2. Here we analysed global NEP from MACC-II and Jena CarboScope atmospheric inversions and ten dynamic global vegetation models ( TRENDY), using statistical models to attribute the trends in NEP to its potential drivers: CO2, climatic variables and land-use change. We found that an increased CO2 was consistently associated with an increased NEP (1995-2014). Conversely, increased temperatures were negatively associated with NEP. Using the two atmospheric inversions and TRENDY, the estimated global sensitivities for CO2 were 6.0 +/- 0.1, 8.1 +/- 0.3 and 3.1 +/- 0.1 PgC per 100 ppm (similar to 1 degrees C increase), and -0.5 +/- 0.2, -0.9 +/- 0.4 and -1.1 +/- 0.1 PgC degrees C-1 for temperature. These results indicate a positive CO2 effect on terrestrial C sinks that is constrained by climate warming.
1.Univ Antwerp, Dept Biol, Ctr Excellence PLECO, Antwerp, Belgium 2.UAB, CSIC, CREAF, Global Ecol Unit, Bellaterra, Spain 3.CREAF, Bellaterra, Spain 4.UVSQ, CNRS, CEA, Lab Sci Climat & Environm, Gif Sur Yvette, France 5.Int Inst Appl Syst Anal, Laxenburg, Austria 6.CSIRO Oceans & Atmosphere, Global Carbon Project, Canberra, ACT, Australia 7.Univ Exeter, Coll Engn Comp & Math, Exeter, Devon, England 8.Peking Univ, Coll Urban & Environm Sci, Sinofrench Inst Earth Syst Sci, Beijing, Peoples R China 9.Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing, Peoples R China
Recommended Citation:
Fernandez-Martinez, M.,Sardans, J.,Chevallier, F.,et al. Global trends in carbon sinks and their relationships with CO2 and temperature[J]. NATURE CLIMATE CHANGE,2019-01-01,9(1):73-+