DOI: 10.1002/2014GB005054
Scopus记录号: 2-s2.0-85027958458
论文题名: The time scale of the silicate weathering negative feedback on atmospheric CO2
作者: Colbourn G ; , Ridgwell A ; , Lenton T ; M
刊名: Global Biogeochemical Cycles
ISSN: 8866236
出版年: 2015
卷: 29, 期: 5 起始页码: 583
结束页码: 596
语种: 英语
英文关键词: carbon cycle
; carbon dioxide
; climate change
; Earth system model
; negative feedback
; silicate weathering
Scopus关键词: carbon cycle
; carbon dioxide
; carbonate
; climate change
; marine atmosphere
; silicate
; timescale
; weathering
英文摘要: The ultimate fate of CO2 added to the ocean-atmosphere system is chemical reaction with silicate minerals and burial as marine carbonates. The time scale of this silicate weathering negative feedback on atmospheric pCO2 will determine the duration of perturbations to the carbon cycle, be they geological release events or the current anthropogenic perturbation. However, there has been little previous work on quantifying the time scale of the silicate weathering feedback, with the primary estimate of 300-400 kyr being traceable to an early box model study by Sundquist (1991). Here we employ a representation of terrestrial rock weathering in conjunction with the "GENIE" (Grid ENabled Integrated Earth system) model to elucidate the different time scales of atmospheric CO2 regulation while including the main climate feedbacks on CO2 uptake by the ocean. In this coupled model, the main dependencies of weathering - runoff, temperature, and biological productivity - were driven from an energy-moisture balance atmosphere model and parameterized plant productivity. Long-term projections (1 Myr) were conducted for idealized scenarios of 1000 and 5000 PgC fossil fuel emissions and their sensitivity to different model parameters was tested. By fitting model output to a series of exponentials we determined the e-folding time scale for atmospheric CO2 drawdown by silicate weathering to be ∼240 kyr (range 170-380 kyr), significantly less than existing quantifications. Although the time scales for reequilibration of global surface temperature and surface ocean pH are similar to that for CO2, a much greater proportion of the peak temperature anomaly persists on this longest time scale; ∼21% compared to ∼10% for CO2. ©2015. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/77971
Appears in Collections: 气候变化事实与影响
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作者单位: College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom; School of Geographical Sciences, University of Bristol, Bristol, United Kingdom; School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom
Recommended Citation:
Colbourn G,, Ridgwell A,, Lenton T,et al. The time scale of the silicate weathering negative feedback on atmospheric CO2[J]. Global Biogeochemical Cycles,2015-01-01,29(5)