Oceanographic aspects of the Eastern Equatorial Pacific.
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Abstract
A noteworthy feature of the flow along the equator is the occasional surface countercurrent to the west of the Galapagos Islands (PuIs, 1895). It ocurrs when the wind stress falls below a certain critical value (0.25 dynes/cm-2 approximately) and appears to represent the surface manifestation of the eastward flowing equatorial undercurrent. An extension of this current past the Galapagos Islands may conceivably lead to "EI Nino" phenomenon of Peru. East of the Galapagos Islands the currents along the equator flow frequently at right angles to the prevailing wind direction. The total mass transport stream line function is computed from more detailed data than have been previously available. It is found that throughout the year the transport is southward along the Peruvian coast and eastward between latitudes 4° N and 6° N. A statistical analysis of long climatic records at Balboa, C.Z. Panama, for the frequency range between zero and six cycles per year failed to bring out any significant non seasonal periodicities. There is a relatively good and inverse relation between temperature and wind, and sea level and wind for frequencies between 1 and 3.5 cycles per year.
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