Long-Term Climate Change Commitment and Reversibility: An EMIC Intercomparison Journal Article


Authors: Zickfeld, Kirsten; Eby, Michael; Weaver, Andrew J.; Alexander, Kaitlin; Crespin, Elisabeth; Edwards, Neil R.; Eliseev, Alexey V.; Feulner, Georg; Fichefet, Thierry; Forest, Chris E.; Friedlingstein, Pierre; Goosse, Hugues; Holden, Philip B.; Joos, Fortunat; Kawamiya, Michio; Kicklighter, David; Kienert, Hendrik; Matsumoto, Katsumi; Mokhov, Igor I.; Monier, Erwan; Olsen, Steffen M.; Pedersen, Jens O. P.; Perrette, Mahe; Philippon-Berthier, Gwenaelle; Ridgwell, Andy; Schlosser, Adam; Von Deimling, Thomas Schneider; Shaffer, Gary; Sokolov, Andrei; Spahni, Renato; Steinacher, Marco; Tachiiri, Kaoru; Tokos, Kathy S.; Yoshimori, Masakazu; Zeng, Ning; Zhao, Fang
Article Title: Long-Term Climate Change Commitment and Reversibility: An EMIC Intercomparison
Abstract: This paper summarizes the results of an intercomparison project with Earth System Models of Intermediate Complexity (EMICs) undertaken in support of the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5). The focus is on long-term climate projections designed to 1) quantify the climate change commitment of different radiative forcing trajectories and 2) explore the extent to which climate change is reversible on human time scales. All commitment simulations follow the four representative concentration pathways (RCPs) and their extensions to year 2300. Most EMICs simulate substantial surface air temperature and thermosteric sea level rise commitment following stabilization of the atmospheric composition at year-2300 levels. The meridional overturning circulation (MOC) is weakened temporarily and recovers to near-preindustrial values in most models for RCPs 2.6-6.0. The MOC weakening is more persistent for RCP8.5. Elimination of anthropogenic CO2 emissions after 2300 results in slowly decreasing atmospheric CO2 concentrations. At year 3000 atmospheric CO2 is still at more than half its year-2300 level in all EMICs for RCPs 4.5-8.5. Surface air temperature remains constant or decreases slightly and thermosteric sea level rise continues for centuries after elimination of CO2 emissions in all EMICs. Restoration of atmospheric CO2 from RCP to preindustrial levels over 100-1000 years requires large artificial removal of CO2 from the atmosphere and does not result in the simultaneous return to preindustrial climate conditions, as surface air temperature and sea level response exhibit a substantial time lag relative to atmospheric CO2.
Keywords: climate change; CO2; SEA-LEVEL RISE; CYCLE; carbon cycle; DIOXIDE EMISSIONS; greenhouse gases; climate models; model comparison; Coupled models; Meteorology Atmospheric Sciences; EARTH SYSTEM MODEL; Climate prediction; CUMULATIVE CARBON EMISSIONS; INTERMEDIATE COMPLEXITY; ANTHROPOGENIC FORCINGS; ATMOSPHERIC LIFETIME
Journal Title: Journal of Climate
Volume: 26
Issue: 16
ISSN: 0894-8755
Publisher: American Meteorological Society  
Publication Place: BOSTON; 45 BEACON ST, BOSTON, MA 02108-3693 USA
Date Published: 2013
Start Page: 5782
End Page: 5809
Language: English
DOI/URL:
Notes: PT: J; NR: 60; TC: 6; J9: J CLIMATE; PG: 28; GA: 196FU; UT: WOS:000322759700004