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Different to classical theories which emphasize east--west feedback along the equator, data analyses via the extreme-point symmetric mode decomposition (ESMD) method support a new viewpoint that the El Ni\~{n}o--Southern Oscillation (ENSO) cycle is horizontally dependent, rather than vertically dependent. The consistency between the ocean current changes and sea-surface temperature anomalies results in a current-generating mechanism for El Ni\~{n}o and La Ni\~{n}a events. The corresponding new findings are as follows: (1) The appearance of the Central Equatorial Countercurrent (CECC) and the enhancement of the North Equatorial Countercurrent (NECC) are primary causes for the occurrences of positive anomalies in the central and eastern Pacific, respectively. (2) In addition to the contribution from the CECC, initiations of the eastern and central Pacific types of El Ni\~{n}o events are mainly caused by the southward transport of warm water from the high-temperature sea-area off Central America, and from the eastern low-speed gap of the NECC, respectively. (3) The northern and southern branches of the South Equatorial Current contribute to the negative anomalies in the eastern and central Pacific, respectively. Particularly, the later transfers cold water from the southeast to the central equatorial Pacific in a direct way, and this implies the crack of the ENSO-asymmetry problem., Comment: 28 pages, 10 figures. Relative to the conventional empirical orthogonal function (EOF) approach, the advantage of the integrated version of our ESMD method goes without saying (please see the fresh figures in the last)! With the help of this new approach, we had found the ocean current generating mechanism for El Ni\~no and La Ni\~na

The relation between El Ni\~{n}o-Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO) perplexes the researchers. Probably, this is due to the default choice on empirical orthogonal function (EOF) method whose outputs are merely static maps without evolution characteristics. To change this situation, the new extreme-point symmetric mode decomposition (ESMD) method is tried. It reveals that: (1) As the ENSO concerned, the key modes are the quarter-decadal and half-decadal ones; (2) As the PDO concerned, the key modes are the half-decadal, decadal and interdecadal ones; (3) The half-decadal mode can be seen as a mutual component for ENSO and PDO and it plays a key part in the so-called "ENSO-like" variation of PDO. In addition, an integrated version of ESMD is developed for time-space evolution. Its outputs have verified the warm-cold shiftings of ENSO and PDO for the most typical episode during 1997-2000., Comment: 12 pages, 5 figures. Relative to the conventional empirical orthogonal function (EOF) approach, the advantage of the integrated version of our ESMD method goes without saying (please see the fresh figures in the last)!