An Eigen Analysis of the Interdecadal Changes in the Structure and Frequency of ENSO Mode
نویسنده
چکیده
The mechanisms of interdecadal changes of El NifioSouthern Oscillation (ENSO) modes are examined through an eigen analysis of a simple coupled ocean-atmosphere model. It is shown that the observed interdecadal climate shift can effectively modify the strength of two major coupled feedbacks for the ENSO mode, namely, the zonal advection and thermocline feedbacks. These modifications lead to quantitative changes of the leading coupled mode in its frequency, growth rate, and spatial pattern, which are consistent with the observation.
منابع مشابه
Changes in the leading ENSO modes associated with the late 1970s climate shift: Role of surface zonal current
[1] In this study, using the nonlinear principal analysis (NLPCA) technique, we demonstrated that the leading El Nino-Southern Oscillation (ENSO) mode in a physical basis changed since the late 1970s. The ENSO mode during the pre-1980s resembles the destabilized ‘ocean basin mode’, while during the post-1980s does ‘the recharge-mode’. In particular, for the pre-1980s, the surface zonal current ...
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