Estimation of vertical diffusion coefficient based on a onedimensional temperature diffusion equation with an inverse method

LIANG Hui; ZHAO Wei; DAI Dejun; ZHANG Jun

doi:10.1007/s13131-014-0472-z

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Article Navigation > Acta Oceanologica Sinica > 2014 > 33(5): 28-36

LIANG Hui, ZHAO Wei, DAI Dejun, ZHANG Jun. Estimation of vertical diffusion coefficient based on a onedimensional temperature diffusion equation with an inverse method[J]. Acta Oceanologica Sinica, 2014, 33(5): 28-36. doi: 10.1007/s13131-014-0472-z

Citation:

LIANG Hui, ZHAO Wei, DAI Dejun, ZHANG Jun. Estimation of vertical diffusion coefficient based on a onedimensional temperature diffusion equation with an inverse method[J]. Acta Oceanologica Sinica, 2014, 33(5): 28-36. doi: 10.1007/s13131-014-0472-z

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Estimation of vertical diffusion coefficient based on a onedimensional temperature diffusion equation with an inverse method

doi: 10.1007/s13131-014-0472-z

1.
Physical Oceanography Laboratory, Ocean University of China, Qingdao 266100, China
2.
The First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China;Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 266061, China
3.
The Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China

Received Date: 2012-04-17
Rev Recd Date: 2013-07-08

Abstract

Abstract

Diapycnal mixing is important in oceanic circulation. An inverse method in which a semi-explicit scheme is applied to discretize the one-dimensional temperature diffusion equation is established to estimate the vertical temperature diffusion coefficient based on the observed temperature profiles. The sensitivity of the inverse model in the idealized and actual conditions is tested in detail. It can be found that this inverse model has high feasibility under multiple situations ensuring the stability of the inverse model, and can be considered as an efficient way to estimate the temperature diffusion coefficient in the weak current regions of the ocean. Here, the hydrographic profiles from Argo floats are used to estimate the temporal and spatial distribution of the vertical mixing in the north central Pacific based on this inverse method. It is further found that the vertical mixing in the upper ocean displays a distinct seasonal variation with the amplitude decreasing with depth, and the vertical mixing over rough topography is stronger than that over smooth topography. It is suggested that the high-resolution profiles from Argo floats and a more reasonable design of the inverse scheme will serve to understand mixing processes.
- inverse method

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