TY - JOUR
T1 - Physics-dynamics coupling in weather, climate, and Earth system models
T2 - Challenges and recent progress
AU - Gross, Markus
AU - Wan, Hui
AU - Rasch, Philip J.
AU - Caldwell, Peter M.
AU - Williamson, David L.
AU - Klocke, Daniel
AU - Jablonowski, Christiane
AU - Thatcher, Diana R.
AU - Wood, Nigel
AU - Cullen, Mike
AU - Beare, Bob
AU - Willett, Martin
AU - Lemarié, Florian
AU - Blayo, Eric
AU - Malardel, Sylvie
AU - Termonia, Piet
AU - Gassmann, Almut
AU - Lauritzen, Peter H.
AU - Johansen, Hans
AU - Zarzycki, Colin M.
AU - Sakaguchi, Koichi
AU - Leung, Ruby
N1 - Funding Information:
Acknowledgments. The authors thank the small army of anonymous referees and editors, in particular Prof. David M. Schultz, who have tirelessly suggested numerous changes and corrections to the manuscript that have significantly improved the manuscript from its previous incarnations (Gross et al. 2016b, 2017). In particular, the authors thank Hillary Weller and John Thuburn for their insightful suggestions, corrections, and moral support, without which this publication would not have been published in this way. No data intrinsic to this publication were used. Further information on the illustrative results presented here can be found in the references cited correspondingly. The National Center for Atmospheric Research is sponsored by the National Science Foundation. Peter Hjort Lauritzen (NCAR) would like to acknowledge the many discussions on high-order methods with Ram D. Nair (NCAR) and thank Paul A. Ullrich (UC Davis) for help on implementing his remapping method. The physgrid work would not have been possible without the support of Steve Goldhaber (NCAR) and Mark A. Taylor (SNL), who were partially funded by the Department of Energy Office of Biological and Environmental Research, work package 12-015334 (Multiscale Methods for Accurate, Efficient, and Scale-Aware Models of the Earth System). Peter Caldwell’s work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. Hui Wan was partially supported by the Linus Pauling Distinguished Postdoctoral Fellowship of the Pacific Northwest National Laboratory (PNNL) through the Laboratory Directed Research and Development Program. Hui Wan, Peter Caldwell, and Phil Rasch acknowledge support from the DOE Office of Science as part of the Scientific Discovery through Advanced Computing (SciDAC) Program. Christiane Jablonowski and Diana Thatcher (University of Michigan) were supported by the DOE Office of Science Grants DE-SC0006684 and DE-SC0003990. Koichi Sakaguchi and L. Ruby Leung were supported by the U.S. Department of Energy Office of Science Biological and Environmental Research as part of the Regional and Global Climate Modeling program, and they used the computational resources from the National Energy Research Scientific Computing Center (NERSC), a DOE User Facility supported by the Office of Science under Contract DE-AC02-05CH11231, and the PNNL Institutional Computing. Koichi Sakaguchi would like to thank Drs. Sara Rauscher (University of Delaware), Chun Zhao (PNNL), and Jin-Ho Yoon (PNNL) for their help on the MPAS simulations and Samson Hagos (PNNL) for helpful discussions. PNNL is operated for DOE by Battelle Memorial Institute under Contract DE-AC05-76RL01830. F. Lemarié and E. Blayo appreciate support from the French national research agency through Contract ANR-14-CE23-0010 (HEAT). The authors acknowledge the contribution to the field made by Jean-François Geleyn during his lifetime. The references to his work just in this paper are a clear testament to his broad and in-depth contributions. Unfortunately, health concerns prohibited him from delivering his keynote lecture at PDC14. Memo-ratus in aeternum. *1950 †8 January 2015.
Publisher Copyright:
© 2018 American Meteorological Society.
PY - 2018
Y1 - 2018
N2 - Numerical weather, climate, or Earth system models involve the coupling of components. At a broad level, these components can be classified as the resolved fluid dynamics, unresolved fluid dynamical aspects (i.e., those represented by physical parameterizations such as subgrid-scale mixing), and nonfluid dynamical aspects such as radiation and microphysical processes. Typically, each component is developed, at least initially, independently.Once development ismature, the components are coupled to deliver a model of the required complexity. The implementation of the coupling can have a significant impact on the model.As the error associated with each component decreases, the errors introduced by the coupling will eventually dominate. Hence, any improvement in one of the components is unlikely to improve the performance of the overall system. The challenges associated with combining the components to create a coherentmodel are here termed physics-dynamics coupling. The issue goes beyond the coupling between the parameterizations and the resolved fluid dynamics. This paper highlights recent progress and some of the current challenges. It focuses on three objectives: to illustrate the phenomenology of the coupling problemwith references to examples in the literature, to show howthe problem can be analyzed, and to create awareness of the issue across the disciplines and specializations. The topics addressed are different ways of advancing full models in time, approaches to understanding the role of the coupling and evaluation of approaches, coupling ocean and atmosphere models, thermodynamic compatibility between model components, and emerging issues such as those that arise as model resolutions increase and/ormodels use variable resolutions.
AB - Numerical weather, climate, or Earth system models involve the coupling of components. At a broad level, these components can be classified as the resolved fluid dynamics, unresolved fluid dynamical aspects (i.e., those represented by physical parameterizations such as subgrid-scale mixing), and nonfluid dynamical aspects such as radiation and microphysical processes. Typically, each component is developed, at least initially, independently.Once development ismature, the components are coupled to deliver a model of the required complexity. The implementation of the coupling can have a significant impact on the model.As the error associated with each component decreases, the errors introduced by the coupling will eventually dominate. Hence, any improvement in one of the components is unlikely to improve the performance of the overall system. The challenges associated with combining the components to create a coherentmodel are here termed physics-dynamics coupling. The issue goes beyond the coupling between the parameterizations and the resolved fluid dynamics. This paper highlights recent progress and some of the current challenges. It focuses on three objectives: to illustrate the phenomenology of the coupling problemwith references to examples in the literature, to show howthe problem can be analyzed, and to create awareness of the issue across the disciplines and specializations. The topics addressed are different ways of advancing full models in time, approaches to understanding the role of the coupling and evaluation of approaches, coupling ocean and atmosphere models, thermodynamic compatibility between model components, and emerging issues such as those that arise as model resolutions increase and/ormodels use variable resolutions.
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U2 - 10.1175/MWR-D-17-0345.1
DO - 10.1175/MWR-D-17-0345.1
M3 - Review article
AN - SCOPUS:85062559967
VL - 146
SP - 3505
EP - 3544
JO - Monthly Weather Review
JF - Monthly Weather Review
SN - 0027-0644
IS - 11
ER -