Assessment of skill and portability in regional marine biogeochemical models : role of multiple planktonic groups
Figure S1: The equations, state variables, parameter formulations and parameter values for Model 3. (241.2Kb)
Figure S5: The equations, state variables, parameter formulations and parameter values for Model 8. (165.6Kb)
Friedrichs, Marjorie A. M.
Dusenberry, Jeffrey A.
Anderson, Laurence A.
Armstrong, Robert A.
Christian, James R.
Doney, Scott C.
Dunne, John P.
Hood, Raleigh R.
McGillicuddy, Dennis J.
Moore, J. Keith
Spitz, Yvette H.
Wiggert, Jerry D.
MetadataShow full item record
KeywordEcosystem model comparison; Biogeochemical data assimilation; Phytoplankton functional groups
Application of biogeochemical models to the study of marine ecosystems is pervasive, yet objective quantification of these models' performance is rare. Here, 12 lower trophic level models of varying complexity are objectively assessed in two distinct regions (equatorial Pacific and Arabian Sea). Each model was run within an identical one-dimensional physical framework. A consistent variational adjoint implementation assimilating chlorophyll-a, nitrate, export, and primary productivity was applied and the same metrics were used to assess model skill. Experiments were performed in which data were assimilated from each site individually and from both sites simultaneously. A cross-validation experiment was also conducted whereby data were assimilated from one site and the resulting optimal parameters were used to generate a simulation for the second site. When a single pelagic regime is considered, the simplest models fit the data as well as those with multiple phytoplankton functional groups. However, those with multiple phytoplankton functional groups produced lower misfits when the models are required to simulate both regimes using identical parameter values. The cross-validation experiments revealed that as long as only a few key biogeochemical parameters were optimized, the models with greater phytoplankton complexity were generally more portable. Furthermore, models with multiple zooplankton compartments did not necessarily outperform models with single zooplankton compartments, even when zooplankton biomass data are assimilated. Finally, even when different models produced similar least squares model-data misfits, they often did so via very different element flow pathways, highlighting the need for more comprehensive data sets that uniquely constrain these pathways.
Author Posting. © American Geophysical Union, 2007. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 112 (2007): C08001, doi:10.1029/2006JC003852.
Showing items related by title, author, creator and subject.
Inconsistent strategies to spin up models in CMIP5 : implications for ocean biogeochemical model performance assessment Seferian, Roland; Gehlen, Marion; Bopp, Laurent; Resplandy, Laure; Orr, James; Marti, Olivier; Dunne, John P.; Christian, James R.; Doney, Scott C.; Ilyina, Tatiana; Lindsay, Keith; Halloran, Paul R.; Heinze, Christoph; Segschneider, Joachim; Tjiputra, Jerry; Aumont, Olivier; Romanou, Anastasia (Copernicus Publications on behalf of the European Geosciences Union, 2016-05-12)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 ...
Toole, Dierdre A.; Siegel, David A.; Doney, Scott C. (American Geophysical Union, 2008-04-12)We evaluate the extent to which dimethylsulfide (DMS) cycling in an open-ocean environment can be constrained and parameterized utilizing emerging evidence for the significant impacts of solar ultraviolet radiation (UVR) ...
Marine ecosystem dynamics and biogeochemical cycling in the Community Earth System Model [CESM1(BGC)] : comparison of the 1990s with the 2090s under the RCP4.5 and RCP8.5 scenarios Moore, J. Keith; Lindsay, Keith; Doney, Scott C.; Long, Matthew C.; Misumi, Kazuhiro (American Meteorological Society, 2013-12-01)The authors compare Community Earth System Model results to marine observations for the 1990s and examine climate change impacts on biogeochemistry at the end of the twenty-first century under two future scenarios ...