Inconsistent strategies to spin up models in CMIP5 : implications for ocean biogeochemical model performance assessment

Date
2016-05-12Author
Seferian, Roland
Concept link
Gehlen, Marion
Concept link
Bopp, Laurent
Concept link
Resplandy, Laure
Concept link
Orr, James
Concept link
Marti, Olivier
Concept link
Dunne, John P.
Concept link
Christian, James R.
Concept link
Doney, Scott C.
Concept link
Ilyina, Tatiana
Concept link
Lindsay, Keith
Concept link
Halloran, Paul R.
Concept link
Heinze, Christoph
Concept link
Segschneider, Joachim
Concept link
Tjiputra, Jerry
Concept link
Aumont, Olivier
Concept link
Romanou, Anastasia
Concept link
Metadata
Show full item recordCitable URI
https://hdl.handle.net/1912/8062As published
https://doi.org/10.5194/gmd-9-1827-2016DOI
10.5194/gmd-9-1827-2016Abstract
During the fifth phase of the Coupled Model Intercomparison Project (CMIP5) substantial efforts were made to systematically assess the skill of Earth system models. One goal was to check how realistically representative marine biogeochemical tracer distributions could be reproduced by models. In routine assessments model historical hindcasts were compared with available modern biogeochemical observations. However, these assessments considered neither how close modeled biogeochemical reservoirs were to equilibrium nor the sensitivity of model performance to initial conditions or to the spin-up protocols. Here, we explore how the large diversity in spin-up protocols used for marine biogeochemistry in CMIP5 Earth system models (ESMs) contributes to model-to-model differences in the simulated fields. We take advantage of a 500-year spin-up simulation of IPSL-CM5A-LR to quantify the influence of the spin-up protocol on model ability to reproduce relevant data fields. Amplification of biases in selected biogeochemical fields (O2, NO3, Alk-DIC) is assessed as a function of spin-up duration. We demonstrate that a relationship between spin-up duration and assessment metrics emerges from our model results and holds when confronted with a larger ensemble of CMIP5 models. This shows that drift has implications for performance assessment in addition to possibly aliasing estimates of climate change impact. Our study suggests that differences in spin-up protocols could explain a substantial part of model disparities, constituting a source of model-to-model uncertainty. This requires more attention in future model intercomparison exercises in order to provide quantitatively more correct ESM results on marine biogeochemistry and carbon cycle feedbacks.
Description
© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Geoscientific Model Development 9 (2016): 1827-1851, doi:10.5194/gmd-9-1827-2016.
Collections
Suggested Citation
Geoscientific Model Development 9 (2016): 1827-1851The following license files are associated with this item:
Related items
Showing items related by title, author, creator and subject.
-
Biogeochemical protocols and diagnostics for the CMIP6 Ocean Model Intercomparison Project (OMIP)
Orr, James C.; Najjar, Raymond G.; Aumont, Olivier; Bopp, Laurent; Bullister, John L.; Danabasoglu, Gokhan; Doney, Scott C.; Dunne, John P.; Dutay, Jean-Claude; Graven, Heather; Griffies, Stephen M.; John, Jasmin G.; Joos, Fortunat; Levin, Ingeborg; Lindsay, Keith; Matear, Richard J.; McKinley, Galen A.; Mouchet, Anne; Oschlies, Andreas; Romanou, Anastasia; Schlitzer, Reiner; Tagliabue, Alessandro; Tanhua, Toste; Yool, Andrew (Copernicus Publications on behalf of the European Geosciences Union, 2017-06-09)The Ocean Model Intercomparison Project (OMIP) focuses on the physics and biogeochemistry of the ocean component of Earth system models participating in the sixth phase of the Coupled Model Intercomparison Project (CMIP6). ... -
Milankovitch forcing and meridional moisture flux in the atmosphere : insight from a zonally averaged ocean–atmosphere model
Antico, Andres; Marchal, Olivier; Mysak, Lawrence A.; Vimeux, Francoise (American Meteorological Society, 2010-09-15)A 1-Myr-long time-dependent solution of a zonally averaged ocean–atmosphere model subject to Milankovitch forcing is examined to gain insight into long-term changes in the planetary-scale meridional moisture flux in the ... -
Impact of circulation on export production, dissolved organic matter, and dissolved oxygen in the ocean : results from Phase II of the Ocean Carbon-cycle Model Intercomparison Project (OCMIP-2)
Najjar, Raymond G.; Jin, X.; Louanchi, F.; Aumont, Olivier; Caldeira, Ken; Doney, Scott C.; Dutay, J.-C.; Follows, Michael J.; Gruber, Nicolas; Joos, Fortunat; Lindsay, Keith; Maier-Reimer, Ernst; Matear, Richard J.; Matsumoto, K.; Monfray, Patrick; Mouchet, Anne; Orr, James C.; Plattner, Gian-Kasper; Sarmiento, Jorge L.; Schlitzer, Reiner; Slater, Richard D.; Weirig, Marie-France; Yamanaka, Yasuhiro; Yool, Andrew (American Geophysical Union, 2007-08-08)Results are presented of export production, dissolved organic matter (DOM) and dissolved oxygen simulated by 12 global ocean models participating in the second phase of the Ocean Carbon-cycle Model Intercomparison Project. ...