Interbasin exchanges and their roles in global ocean circulation: A study based on 1400 years' spin up of MOM4p1

Zhu Yaohua; Wei Zexun; Fang Guohong; Wang Yonggang; Guan Yuping

Article Contents

Article Navigation > Haiyang Xuebao > 2014 > 36(2): 1-15

Zhu Yaohua, Wei Zexun, Fang Guohong, Wang Yonggang, Guan Yuping. Interbasin exchanges and their roles in global ocean circulation: A study based on 1400 years' spin up of MOM4p1[J]. Haiyang Xuebao, 2014, 36(2): 1-15.

Citation:

PDF( 7159 KB)

Interbasin exchanges and their roles in global ocean circulation: A study based on 1400 years' spin up of MOM4p1

1.
Key Laboratory of Marine Science and Numerical Modeling,First Institute of Oceanography,State Oceanic Administration,Qingdao 266061,China
2.
State Key Laboratory of Tropical Oceanography,South China Sea Institute of Oceanology,Chinese Academy of Sciences,Guangzhou 510301,China

Received Date: 2013-09-18
Rev Recd Date: 2013-11-25

Abstract

Abstract

A global prognostic model based on Mom4p1,which is a primitive equation nonBoussinesq numerical model,has been integrated 1 400 years from the state of rest based on the realistic topography to study the long term pattern of combined wind-driven and thermodynamically-driven general circulation.The model is driven by monthly climatological mean forces and includes 192×189 horizontal grids and 31 pressure based vertical levels.The main objective is to investigate the mass and heat transports at interbasin passagesand their compensations and roles in the global ocean circulation under equilibrium state of long term spin up.The kinetic energy analysis divides the spin up process into three stages:the quasi-stable state of wind driven current,the growing phase of thermodynamical circulation and the equilibrium state of thermohaline circulation. It is essential to spin up over a thousand years in order to reach the thermohaline equilibrium state from a state of rest. The Arctic Throughflow from the Bering Strait to the Greenland Sea and the Indonesian Throughflow(ITF) are captured and examined with their compensations and existing data. Analysis reveals that the slope structures of sea surface height are the dynamical driving mechanism of the Pacific-Arctic-Atlantic throughflow and ITF. The analysis denotes,in spite of 1.4×10⁶ m³/s of the southward volume transport in the northern Atlantic,there is still 1×10¹⁵W of heat transported northward since the northward currents in upper layer carry much higher temperature water than the southward flowing northern Atlantic deep water(NADW).Meridional volume and heat transports are focused on the contributions to NADW renewals and Atlantic meridional overturning circulation(AMOC). Quantitative descriptions of the interbasin exchanges are explained by meridional compensations and supported by previous observations and numerical modeling results. Analysis indicates that the volume and heat exchanges on the interbasin passages proposed in this article manifest their hub roles in the Great Ocean Conveyor system.
- numerical modeling,
- global ocean,
- interbasin exchange,
- meridional transport,
- meridional overturning circulation

FullText(HTML)

References(20)

References

Broecker W S. The great ocean conveyor[J]. Oceanogr,1991,4:79-89.

Broecker W S. The biggest chill[J]. Nat Hist Mag,1987,97:74-82.

Schmitz W J. On the interbasin-scale thermohaline circulation[J]. Rev Geophys,1995,33:151-173.

Huisman S E,Dijkstra H A,Hegdt A S von der,et al. Robustness of multiple equilibria in the global ocean circulation[J]. Geophys Research Letters,2009,36(1):L01610.

Marotzke J,Willebrand J. Multiple equilibria of the global thermohaline circulation[J]. J Phys Oceanogr,1991,21:1372-1385.

Wei Z,Choi B,Fang G. Water,heat and salt transports from diagnostic world ocean and north Pacific circulation models[J].La Mer,2000,38:211-218.

Dong S,Garzoli S,Baringer M. The role of interocean exchanges on decadal variations of the meridional heat transport in the South Atlantic[J]. J Phys Oceanogr,2011,41:1498-1511.

Griffies S M. Elements of Mom4p1 //GFDL Ocean Group Technical Report. 2010,6.

Levitus S,Boyer T. World Ocean Atlas[M]. Washington D C:NOAA,1994:1-117.

Hellerman S,Rosenstein M. Normal monthly wind stress over the world ocean with error estimates[J]. J Phys Oceanogr,1983,13:1093-1104.

Overland J E,Roach A T. Northward flow in the Bering and Chukchi Seas[J]. J Geophys Res,1987,92(C7):7097-7106.

Li L,Du L,Zhao J P,et al. The fundamental characteristics of current in the Bering Strait and the Chukchi Sea from July to September 2003[J]. Acta Oceanologica Sinica,2005,24(6):1-11.

Woodgate R A,Aagaard K,Weingartner T. A year in the physical oceanography of the Chukchi Sea:Moored measurements from autumn 1990-1991. Part Ⅱ:Topical Studies in Oceanography[J]. Deep-Sea Research,2005,52:3116-3149.

Gordon A L. Interocean exchange of thermocline water[J].J Geophys Res,1986,91:5037-5046.

Hall M M,Bryden H L. Direct estimates and mechanismsof ocean heat transport[J]. Deep-Sea Res,1982,29(3A):339-359.

Ganachaud A,Wunsch C. Large-scale ocean heat and freshwater transports during the world ocean circulation experiment[J].J Climate,2002,16:696-705.

Ganachaud A,Wunsch C. Improved estimates of global ocean circulation,heat transport and mixing from hydrographic data[J]. Nature,2000,408,453-457.

Trenberth K E,Caron J M,Stepaniak D P. The atmospheric energy budget and implications for surface fluxes and ocean heat transports[J]. Climate Dynamics,2001,17:259-276.

Roemmich D H,Wunsch C. Two transatlanticsections:Meridional circulation and heat flux in thesubtropical North Atlantic Ocean[J]. Deep-Sea Res,1985,32:619-664.

Talley L D. Data-based meridionaloverturning streamfunctions for the global ocean[J].J Clim,2003,16:3213-3226.

Relative Articles

Supplements(0)

Cited By

Proportional views