Main periodicities of the minimum extreme temperature of three stations near the Mexican Pacific coast



Three minimum extreme temperature series from meteorological stations located in or near the Mexican Pacific coast, Acapulco, Comitán and Manzanillo, are spectrally analyzed. The series cover a period from 1941 to 1981. The spectral analysis indicates that a significant quasiquinquenial periodicity (~5 yrs) is present in Comitán and Manzanillo, even more, Acapulco also shows a frequency ~5yr if the uncertainties are taken into account. This spectral peak can be considered either as related to solar activity or to strong El Niño events. The remaining periodicities can be associated to meteorological phenomena like El Niño and the quasi-biennial oscillation or to some solar activity phenomena. Furthermore, the behavior deduced from a coherence spectra analysis between the temperature and the Southern Oscillation Index, considered as a proxy of El Niño, and sunspot number, considered as a proxy of solar activity, indicates that the stations closer to the ocean might be more influenced by El Niño than by solar activity, while the station inland has both influences.


Minimum extreme temperature; Mexican Pacific coast; solar activity

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