Evaluation of the terrestrial carbon cycle, future plant geography and climate‐carbon cycle feedbacks using five Dynamic Global Vegetation Models (DGVMs)

摘要: This study tests the ability of five Dynamic Global Vegetation Models (DGVMs), forced with observed climatology and atmospheric CO2, to model contemporary global carbon cycle. The DGVMs are also coupled a fast ‘climate analogue model’, based on Hadley Centre General Circulation Model (GCM), run into future for four Special Report Emission Scenarios (SRES): A1FI, A2, B1, B2. Results show that all consistent land budget. Under more extreme projections environmental change, responses diverge markedly. In particular, large uncertainties associated response tropical vegetation drought boreal ecosystems elevated temperatures changing soil moisture status. divergence in their regional changes climate than increases CO2 content. All models simulate release climate, when physiological effects plant production not considered, implying positive terrestrial climate-carbon cycle feedback. reduction net primary (NPP) decrease residence time tropics extra-tropics climate. When both counteracting ecosystem function cumulative uptake over 21st century SRES emission scenarios. However, most A1FI emissions scenario, three out an annual source from atmosphere final decades century. For this differs by 494 Pg C among uncertainty is equivalent 50 years anthropogenic at current levels.