Ocean mode (or quasigeostrophic wave) analysis is one of the key data processing technique in oceanic acoustic tomography experiment. A primary study on its application foreground in Navy Oceanography is put forward w...Ocean mode (or quasigeostrophic wave) analysis is one of the key data processing technique in oceanic acoustic tomography experiment. A primary study on its application foreground in Navy Oceanography is put forward with CTD data and Carton oceanic assimilation data. It shows that the sound speed mode is not well orthogonal to each other, so that it is practically no use. However, the current mode calculated from the CTD data collected in summer as the position with weak stochastic processes and strong geostrophic balance is well orthogonal to each other, it can be used everywhere in the ocean of the similar water mass at any time as long as the basic condition serves. It can be used for decomposition and reconstruction of dynamic or quasi-dynamic factors such as seawater temperature, from which and average of salinity the sound speed profile can be composed. It also shows that the monthly James Carton assimilation data is well consistent with observation ones in subsurface layer in the region with weak current speed but not well below subsurface layer or near the Kuroshio in the western Pacific. By running a nested ocean general circulation model with adjusted vertical eddy diffusivity to do data assimilation again and applying current mode analysis to reconstruct or compose related factors, it is hopefully possible to improve the precision and space resolution of the oceanic assimilation data. So that, it is definitely possible to obtain the three dimensional high resolution distribution of ocean sound speed in real time with the satellite SST and surface wind fields only.展开更多
文摘Ocean mode (or quasigeostrophic wave) analysis is one of the key data processing technique in oceanic acoustic tomography experiment. A primary study on its application foreground in Navy Oceanography is put forward with CTD data and Carton oceanic assimilation data. It shows that the sound speed mode is not well orthogonal to each other, so that it is practically no use. However, the current mode calculated from the CTD data collected in summer as the position with weak stochastic processes and strong geostrophic balance is well orthogonal to each other, it can be used everywhere in the ocean of the similar water mass at any time as long as the basic condition serves. It can be used for decomposition and reconstruction of dynamic or quasi-dynamic factors such as seawater temperature, from which and average of salinity the sound speed profile can be composed. It also shows that the monthly James Carton assimilation data is well consistent with observation ones in subsurface layer in the region with weak current speed but not well below subsurface layer or near the Kuroshio in the western Pacific. By running a nested ocean general circulation model with adjusted vertical eddy diffusivity to do data assimilation again and applying current mode analysis to reconstruct or compose related factors, it is hopefully possible to improve the precision and space resolution of the oceanic assimilation data. So that, it is definitely possible to obtain the three dimensional high resolution distribution of ocean sound speed in real time with the satellite SST and surface wind fields only.
