气候变化领域集成服务门户(CCPortal): Ocean Kinetic Energy Backscatter Parametrization on Unstructured Grids: Impact on Global Eddy-Permitting Simulations

CCPortal

DOI	10.1029/2019MS001855
	Ocean Kinetic Energy Backscatter Parametrization on Unstructured Grids: Impact on Global Eddy-Permitting Simulations
	Juricke S.; Danilov S.; Koldunov N.; Oliver M.; Sidorenko D.
发表日期	2020
ISSN	19422466
卷号	12 期号:1
英文摘要	In this study we demonstrate the potential of a kinetic energy backscatter scheme for use in global ocean simulations. Ocean models commonly employ (bi)harmonic eddy viscosities causing excessive dissipation of kinetic energy in eddy-permitting simulations. Overdissipation not only affects the smallest resolved scales but also the generation of eddies through baroclinic instabilities, impacting the entire wave number spectrum. The backscatter scheme returns part of this overdissipated energy back into the resolved flow. We employ backscatter in the FESOM2 multiresolution ocean model with a quasi-uniform 1/4° (Formula presented.) mesh. In multidecadal ocean simulations, backscatter increases eddy activity by a factor 2 or more, moving the simulation closer to observational estimates of sea surface height variability. Moreover, mean sea surface height, temperature, and salinity biases are reduced. This amounts to a globally averaged bias reduction of around 10% for each field, which is even larger in the Antarctic Circumpolar Current. However, in some regions such as the coastal Kuroshio, backscatter leads to a slight overenergizing of the flow and, in the Antarctic, to an unrealistic reduction of sea ice. Some of the bias increases can be reduced by a retuning of the model, and we suggest related adjustments to the backscatter scheme. The backscatter simulation is about 2.5 times as expensive as a simulation without backscatter. Most of the increased cost is due to a halving of the time step to accommodate higher simulated velocities. © 2019. The Authors.
英文关键词	eddy-permitting resolution; inverse energy cascade; ocean kinetic energy backscatter; subgrid eddy parametrization; viscosity closure
语种	英语
scopus关键词	Kinetic energy; Kinetics; Ocean currents; Sea ice; Surface waters; Viscosity; Antarctic Circumpolar Currents; Baroclinic instability; Eddy-permitting resolution; Inverse energy cascades; Mean sea surface heights; Parametrizations; Sea surface height; Wavenumber spectra; Backscattering; backscatter; baroclinic instability; global ocean; kinetic energy; parameterization; sea surface height; simulation; viscosity; Antarctic Circumpolar Current; Kuroshio Current; Southern Ocean
来源期刊	Journal of Advances in Modeling Earth Systems
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/156779
作者单位	Mathematics, Jacobs University, Bremen, Germany; Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany; MARUM-Center for Marine Environmental Sciences, Bremen, Germany
推荐引用方式 GB/T 7714	Juricke S.,Danilov S.,Koldunov N.,et al. Ocean Kinetic Energy Backscatter Parametrization on Unstructured Grids: Impact on Global Eddy-Permitting Simulations[J],2020,12(1).
APA	Juricke S.,Danilov S.,Koldunov N.,Oliver M.,&Sidorenko D..(2020).Ocean Kinetic Energy Backscatter Parametrization on Unstructured Grids: Impact on Global Eddy-Permitting Simulations.Journal of Advances in Modeling Earth Systems,12(1).
MLA	Juricke S.,et al."Ocean Kinetic Energy Backscatter Parametrization on Unstructured Grids: Impact on Global Eddy-Permitting Simulations".Journal of Advances in Modeling Earth Systems 12.1(2020).