气候变化领域集成服务门户(CCPortal): A review of the major drivers of the terrestrial carbon uptake: Model-based assessments, consensus, and uncertainties

CCPortal

DOI	10.1088/1748-9326/ab3012
	A review of the major drivers of the terrestrial carbon uptake: Model-based assessments, consensus, and uncertainties
	Tharammal T.; Bala G.; Devaraju N.; Nemani R.
发表日期	2019
ISSN	17489318
卷号	14 期号:9
英文摘要	Terrestrial and oceanic carbon sinks together sequester >50% of the anthropogenic emissions, and the major uncertainty in the global carbon budget is related to the terrestrial carbon cycle. Hence, it is important to understand the major drivers of the land carbon uptake to make informed decisions on climate change mitigation policies. In this paper, we assess the major drivers of the land carbon uptake - CO2 fertilization, nitrogen deposition, climate change, and land use/land cover changes (LULCC) - from existing literature for the historical period and future scenarios, focusing on the results from fifth Coupled Models Intercomparison Project (CMIP5). The existing literature shows that the LULCC fluxes have led to a decline in the terrestrial carbon stocks during the historical period, despite positive contributions from CO2 fertilization and nitrogen deposition. However, several studies find increases in the land carbon sink in recent decades and suggest that CO2 fertilization is the primary driver (up to 85%) of this increase followed by nitrogen deposition (∼10%-20%). For the 21st century, terrestrial carbon stocks are projected to increase in the majority of CMIP5 simulations under the representative concentration pathway 2.6 (RCP2.6), RCP4.5, and RCP8.5 scenarios, mainly due to CO2 fertilization. These projections indicate that the effects of nitrogen deposition in future scenarios are small (∼2%-10%), and climate warming would lead to a loss of land carbon. The vast majority of the studies consider the effects of only one or two of the drivers, impairing comprehensive assessments of the relative contributions of the drivers. Further, the broad range in magnitudes and scenario/model dependence of the sensitivity factors pose challenges in unambiguous projections of land carbon uptake. Improved representation of processes such as LULCC, fires, nutrient limitation and permafrost thawing in the models are necessary to constrain the present-day carbon cycle and for more accurate future projections. © 2019 The Author(s). Published by IOP Publishing Ltd.
语种	英语
scopus关键词	Budget control; Carbon; Carbon dioxide; Climate models; Land use; Nitrogen; Anthropogenic emissions; Climate change mitigation; Comprehensive assessment; Land use/land cover change; Nutrient limitations; Relative contribution; Sensitivity factors; Terrestrial carbon cycle; Climate change; anthropogenic source; assessment method; carbon budget; carbon dioxide; carbon sink; climate change; CMIP; nutrient limitation; permafrost; uncertainty analysis
来源期刊	Environmental Research Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/154387
作者单位	Center for Atmospheric and Oceanic Sciences, Indian Institute of Science, Bangalore, India; Laboratoire des Sciences du Climat et de l'Environnement LSCE/IPSL, Unité Mixte CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, F-91191, France; NASA Ames Research Center, Moffett Field, CA 94035, United States
推荐引用方式 GB/T 7714	Tharammal T.,Bala G.,Devaraju N.,et al. A review of the major drivers of the terrestrial carbon uptake: Model-based assessments, consensus, and uncertainties[J],2019,14(9).
APA	Tharammal T.,Bala G.,Devaraju N.,&Nemani R..(2019).A review of the major drivers of the terrestrial carbon uptake: Model-based assessments, consensus, and uncertainties.Environmental Research Letters,14(9).
MLA	Tharammal T.,et al."A review of the major drivers of the terrestrial carbon uptake: Model-based assessments, consensus, and uncertainties".Environmental Research Letters 14.9(2019).