Biennial, interannual, and decadal signals in the Pacific basin are observed to share patterns and evolution in covarying sea surface temperature (SST), 18°C isotherm depth (Z18), zonal surface wind (ZSW), and wind stress curl (WSC) anomalies from 1955 to 1999. Each signal has warm SST anomalies propagating slowly eastward along the equator, generating westerly ZSW anomalies in their wake. These westerly ZSW anomalies produce cyclonic WSC anomalies off the equator which pump baroclinic Rossby waves in the western/central tropical North Pacific Ocean. These Rossby waves propagate westward, taking ∼6, ∼12, and ∼36 months to reach the western boundary near ∼7°N, ∼12°N, and ∼18°N on biennial, interannual, and decadal...
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