Abstract:
Previous statistical analyses of eddy characteristics have focused primarily on extratropical oceans or on global integrated properties, with a notable lack of research on the features and statistics of near-equatorial mesoscale eddies. The equatorial Pacific is a region of global climate importance, where eddy-induced heat fluxes play an important role in ENSO events. Therefore, the study of near-equatorial eddies is of great importance to ocean circulation and climate. This study utilizes a dataset of satellite altimetry-based eddy identification and tracking analysis to investigate the spatiotemporal distribution and generation-to-demise patterns of eddies in the near-equatorial Pacific from 1993 to 2020. Statistical analysis reveals the equatorial Pacific as a net eddy source region, with eddies moving predominant westward and poleward. Eddies with lifespan of at least 4 weeks generate a westward net transport of about 13 Sv and a poleward net transport of about 1 Sv. The zonal-averaged eddy kinetic energy shows a peak to the north of the equator, decreasing nearly symmetrically toward higher latitudes. Significant variability associated with ENSO is observed, with eddy size and amplitude correlating negatively, while eddy occurrence frequency correlating positively, with the Niño 3.4 index. These results help understand the role of eddies in climate variability.