Diagnostic Analysis And Research Of Numerical Test Of The Interaction Between The Wind Stress Over The Tropical Pacific And SST

This paper studies the interaction relationship between the Wind Stress (wind) field over the tropical Pacific and SST by use of the diagnostic analysis and numerical simulation on the basis of SST,850hpa wind data from NCEP/NCAR and FSU wind stress data. The results show that the leading wind stress anomalies field is correlated well with Nino3 SSTA and the correlation has appeared when the wind stress is prior to Nino3 SSTA by 8 months. With the reduction of the leading time, the location of the zonal wind stress area influencing Nino3 SSTA expands toward the middle Pacific from the eastern Pacific, as well as the meridional wind stress in the eastern Pacific and the western Pacific. Numerical studies suggest that the wind stress over strong correlation areas which contributes to the interannual variance of SST is of little role on the development and maintenance of climatological state of the tropical Pacific, Instead of the wind stress over non-strong correlation areas. The numerical tests on the basis of SVD analysis between the wind stress over the tropical Pacific and SST demonstrate that the tropical Pacific only forced by the first 4 wind stress with the biggest percentage of the sum of square covariance can form climatological field and SST anomalies almost coincident with the practical cases. Also find that there mainly occur the eastern El Nino before 1980s, instead , mainly occurring the middle El Nino before 1980s, and there are obvious differences for the leading wind field pattern associated with the two kinds of El Nino events. Moreover, as for average state, the crucial areas of wind stress acting on the two kinds of El Nino exist different sites, and the zonal wind stress play a important role on eastern El Nino models, the meridional wind stress ,however, play a significant effect on the middle El Nino models.