In this study, the dynamic mechanisms of interannual sea surface height （SSH） variability are investigated based on the first-mode baroclinic Rossby wave model, with a focus on the effects of different levels of win...In this study, the dynamic mechanisms of interannual sea surface height （SSH） variability are investigated based on the first-mode baroclinic Rossby wave model, with a focus on the effects of different levels of wind stress curl （WSC）. Maximum covariance analysis （MCA） of WSC and SSH anomalies displays a mode with significant WSC anomalies located primarily in the mid-latitude eastern North Pacific and central tropical Pacific with corresponding SSH anomalies located to the west. This leading mode can be attributed to Ekman pumping induced by local wind stress and the westward-propagating Rossby wave driven by large- scale wind stress. It is further found that in the middle latitudes, the SSH anomalies are largely determined by WSC variations associated with the North Pacific Gyre Oscillation （NPGO）, rather than the Pacific Decadal Oscillation （PDO）. The sensitivity of the predictive skill of the linear first-mode baroclinic model to different wind products is also examined.展开更多
The climate modulation on the sea surface height （SSH） in China seas is investigated using a China Ocean Reanalysis （CORA） dataset from 1958-2008. The dataset is constructed by assimilating the temperature/salinit...The climate modulation on the sea surface height （SSH） in China seas is investigated using a China Ocean Reanalysis （CORA） dataset from 1958-2008. The dataset is constructed by assimilating the temperature/salinity profiles derived from the satellite altimetry data and historical observational temperature/salinity profiles. Based on the Empirical Orthogonal Function （EOF）, the CORA sea surface height anomaly （SSHa） is decomposed, and the interannual and decadal variability of the first three leading modes are analyzed. On the interannual timescale, the first principal component （PC1） is significant positively correlated with the E1 Nifio/Southern Oscillation （ENSO）. On the decadal timescale, North Pacific Gyre Oscillation （NPGO） has significant negative correlation with PC 1 whereas Pacific Decadal Oscillation （PDO） is in phase with PC3. Analysis shows that the decadal variability of SSH is mainly modulated by the wind stress curl variability related to the NPGO and PDO. In addition, the effect of net heat flux associated to the NPGO and PDO on SSH is also investigated, with net heat flux variability in the Luzon strait and tropic Pacific found to influence the decadal variability of SSH.展开更多
基金funded by the National Basic Research Program of China (Grant No 2007CB411800)
文摘In this study, the dynamic mechanisms of interannual sea surface height （SSH） variability are investigated based on the first-mode baroclinic Rossby wave model, with a focus on the effects of different levels of wind stress curl （WSC）. Maximum covariance analysis （MCA） of WSC and SSH anomalies displays a mode with significant WSC anomalies located primarily in the mid-latitude eastern North Pacific and central tropical Pacific with corresponding SSH anomalies located to the west. This leading mode can be attributed to Ekman pumping induced by local wind stress and the westward-propagating Rossby wave driven by large- scale wind stress. It is further found that in the middle latitudes, the SSH anomalies are largely determined by WSC variations associated with the North Pacific Gyre Oscillation （NPGO）, rather than the Pacific Decadal Oscillation （PDO）. The sensitivity of the predictive skill of the linear first-mode baroclinic model to different wind products is also examined.
基金Supported by the National Basic Research Program of China(973 Program)(No.2013CB430304)the National Natural Science Foundation of China(Nos.41176003,41206178,41376013,41376015,41306006)+1 种基金the National High Technology Research and Development Program of China(863 Program)(No.2013AA09A505)the Global Change and Air-Sea Interaction of China(No.GASI-01-01-12)
文摘The climate modulation on the sea surface height （SSH） in China seas is investigated using a China Ocean Reanalysis （CORA） dataset from 1958-2008. The dataset is constructed by assimilating the temperature/salinity profiles derived from the satellite altimetry data and historical observational temperature/salinity profiles. Based on the Empirical Orthogonal Function （EOF）, the CORA sea surface height anomaly （SSHa） is decomposed, and the interannual and decadal variability of the first three leading modes are analyzed. On the interannual timescale, the first principal component （PC1） is significant positively correlated with the E1 Nifio/Southern Oscillation （ENSO）. On the decadal timescale, North Pacific Gyre Oscillation （NPGO） has significant negative correlation with PC 1 whereas Pacific Decadal Oscillation （PDO） is in phase with PC3. Analysis shows that the decadal variability of SSH is mainly modulated by the wind stress curl variability related to the NPGO and PDO. In addition, the effect of net heat flux associated to the NPGO and PDO on SSH is also investigated, with net heat flux variability in the Luzon strait and tropic Pacific found to influence the decadal variability of SSH.
