%0 journal article
%@ 0022-3670
%A Tang, S., Storch, H.v., Chen, X.

%D 2020
%J Journal of Physical Oceanography
%N 1
%P 133-144 
%R doi:10.1175/JPO-D-19-0144.1
%T Atmospherically forced regional ocean simulations of the South China Sea: Scale-dependency of the signal-to-noise ratio
%U https://doi.org/10.1175/JPO-D-19-0144.1
1 
%X When subjecting ocean models to atmospheric forcing, the models exhibits two types of variability – a response to the external forcing (hereafter referred to as signal) and inherently generated (internal; intrinsic; unprovoked; chaotic) variations (hereafter referred to as noise). Based on an ensemble of simulations with identical atmospherically forced oceanic models which differ only in the initial conditions at different times, the signal-to-noise ratio of the atmospherically forced oceanic model is determined. In the large-scales, the variability of the model output is mainly induced by the external forcing and the proportion of the internal variability is small, so the signal-to-noise ratio is large. For smaller scales, the influence of the external forcing weakens and the influence of the internal variability strengthens, so the signal-to-noise ratio becomes less and less. Thus, the external forcing is dominant for large scales, while most of the variability is internally generated for small scales.