OS042-0009
Evaluation of global ocean–sea-ice model simulations based on the experimental protocols of the Ocean Model Intercomparison Project phase 2 (OMIP-2)
Tuesday, 15 December 2020
Poster
Hiroyuki Tsujino1, Shogo Urakawa2, Stephen Griffies3, Gokhan Danabasoglu4, Alistair Adcroft5, Arthur E Amaral6, Arsouze Thomas6, Mats Bentsen7, Raffaele Bernardello8, Claus W Boning9, Alexandra Bozec10, Eric P. Chassignet10, Sergey Danilov11, Raphael Dussin3, Eleftheria Exarchou6, Pier Giuseppe Fogli12, Baylor Fox-Kemper13, Chuncheng Guo7, Mehmet Ilicak7,14, Doroteaciro Iovino15, Who M Kim4, Nikolay Koldunov16, Yoshiki Komuro17, Vladimir Lapin6, Yiwen Li18, Pengfei Lin19, Keith T Lindsay20, Hailong Liu19, Matthew C Long21, Simon James Marsland22, Simona Masina23, Aleksi Nummelin7, Jan Klaus Rieck9, Yohan Ruprich-Robert6, Markus Scheinert24, Valentina Sicardi8, Dmitry Sidorenko25, Tatsuo Suzuki26, Hiroaki Tatebe27, Qiang Wang11, Stephen G Yeager28 and Zipeng Yu29, (1)Meteorological Research Institute, Japan Meteorological Agency, Ibaraki, Japan, (2)Meteorological Research Institute, Japan Meteorological Agency, Tsukuba, Japan, (3)Geophysical Fluid Dynamics Laboratory, Princeton, NJ, United States, (4)National Center for Atmospheric Research, Boulder, CO, United States, (5)Princeton University, Princeton, NJ, United States, (6)Barcelona Supercomputing Center, Barcelona, Spain, (7)NORCE Norwegian Research Centre, Bjerknes Centre for Climate Research, Bergen, Norway, (8)Barcelona Supercomputing Center, Earth Sciences, Barcelona, Spain, (9)GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany, (10)Center for Ocean-Atmospheric Prediction Studies, Florida State University, Tallahassee, FL, United States, (11)Alfred Wegener Institute Helmholtz-Center for Polar and Marine Research Bremerhaven, Bremerhaven, Germany, (12)Fondazione CMCC, Bologna, Italy, (13)Brown University, Earth, Environmental and Planetary Sciences, Providence, RI, United States, (14)Istanbul Technical University, Eurasia Institute of Earth Sciences, Istanbul, Turkey, (15)Euro-Mediterranean Center on Climate Change Foundation, Bologna, Italy, (16)MARUM‐Center for Marine Environmental Sciences, Bremen, Germany, Bremen, Germany, (17)JAMSTEC, Yokohama, Kanagawa, Japan, (18)State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences, Beijing, China, (19)State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences, Beijing, 100029, China, Beijing, China, (20)NCAR, Boulder, CO, United States, (21)National Center for Atm Res, Boulder, CO, United States, (22)CSIRO Ocean and Atmospheric Research Aspendale, Aspendale, VIC, Australia, (23)Euro-Mediterranean Center on Climate Change, Ocean Modelling and Data Assimilation, Bologna, Italy, (24)GEOMAR, Kiel, Germany, (25)Alfred Wegener Institute Helmholtz-Center for Polar and Marine Research, Bremerhaven, Germany, (26)JAMSTEC Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan, (27)JAMSTEC Japan Agency for Marine-Earth Science and Technology, Research Center for Environmental Modeling and Application, Yokohama, Japan, (28)NCAR, Oceanography, Boulder, CO, United States, (29)LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
Abstract:
We present a new framework for global ocean–sea-ice model simulations based on phase 2 of the Ocean Model Intercomparison Project (OMIP-2), making use of the JRA55-do atmospheric dataset. We motivate the use of OMIP-2 over the framework for the first phase of OMIP (OMIP-1), previously referred to as the Coordinated Ocean–ice Reference Experiments (CORE), via the evaluation of OMIP-1 and OMIP-2 simulations from eleven (11) state-of-the-science global ocean–sea-ice models. In the present evaluation, multi-model ensemble means and spreads are calculated separately for the OMIP-1 and OMIP-2 simulations and overall performances are assessed considering metrics commonly used by ocean modelers. Both OMIP-1 and OMIP-2 multi-model ensemble ranges capture observations in more than 80% of the time and region for most metrics, with the multi-model ensemble spread greatly exceeding the difference between the means of the two datasets. Many features, including some climatologically relevant ocean circulation indices, are very similar between OMIP-1 and OMIP-2 simulations, and yet we could also identify key qualitative improvements in transitioning from OMIP-1 to OMIP-2. For example, the sea surface temperature of the OMIP-2 simulations reproduce the observed global warming during the 1980s and 1990s, as well as the warming slowdown in the 2000s and the more recent accelerated warming, which were absent in OMIP-1. A negative bias in the sea-ice concentration in summer of both hemispheres in OMIP-1 is reduced in OMIP-2. The overall reproducibility of both seasonal and interannual variations in sea surface temperature and sea surface height (dynamic sea level) is improved in OMIP-2. These improvements represent a new capability of the OMIP-2 framework for evaluating process-level responses using simulation results. Many of the remaining common model biases may be attributed either to errors in representing important processes in ocean–sea-ice models, or to shared biases and limitations in the atmospheric forcing. We suggest that such problems can be resolved through collaboration between those developing models (including parameterizations) and forcing datasets.
Overall, the present assessment justifies our recommendation that future model development and analysis studies use the OMIP-2 framework.
