Numerical study on multidecadal changes of upper ocean thermal condition in the South China Sea

By hydrographic data and validated ocean reanalysis data during 1960-2015, Chiang et al. (2018) have proposed multidecadal changes of upper ocean thermal conditions in the South China Sea (SCS). Compared with the accumulated trend of upper ocean heat content (UOHC) in the western Pacific enhancing in the latter 3 decades of 1986-2015, that in the SCS slightly slowed down. Such a multidecadal change of UOHC was suggested to be mainly attributed to the Pacific-Decadal-Oscillation-related sea surface temperature and to be further modulated by the isothermal variability induced by the basin-scale SCS circulation. In the present study, an ocean circulation model covering the entire SCS (the SCS model) is established to investigate the proposed multidecadal changes of UOHC. By conducting a series of numerical experiments with the SCS model, the dynamical processes resulting in the UOHC variability are clarified.

Chiang et al. (2018): Multidecadal changes of upper-ocean thermal conditions in the tropical northwest Pacific Ocean versus South China Sea during 1960-2015. Journal of Climate, 31(10), 3999-4016, doi:10.1175/JCLI-D-17-0394.1.