SIGNAL PROPAGATION IN SEA-LEVEL DATA FROM THE WEST-COAST OF MEXICO

Six months series of meteorological and sera level data, corresponding to summer and winter periods, were analyzed by complex empirical orthogonal functions on time domain, in 0.25 to 0.01 cpd frequency band. Five cases were analyzed: summer of 1962, winter of 1965, summers average, winters average and all semesters average (including summer and winter). Results show sea level events propagating northward during the summer, this events are not present during winter. This is concordant with other authors studies for the same zone, using other methods. Wavelength is of about 9 000 km and there is two kinds: one that propagates from Salina Cruz to Mazatlan, not entering the Gulf of California, and other (longer than the first), that travels from Acapulco to Guaymas, entering the Gulf of California. Atmospheric pressure events are detected propagating northward, with an estimated wavelength of thousands of km and are considered doubtfull, because they are much longer than the study zone. In general, this method results are qualitatively comparable with the original series physics, but it is considered that quantitatively overestimates the wavelength of propagating events.