Geological and Archaeological Evidence of El Ni???±o Events along the Coast of El Oro Province Ecuador: Excavations at La Emerenciana a LateValdivia (ca. 2200 1450 B.C.) Ceremonial Center

摘要

El Ni?o-Southern Oscillation is a band of anomalously warm ocean water related to changes in oceanic currents and trade winds. El Ni?o represents a general warming of surface sea temperatures along the Eastern Pacific, and a lessening or reversal of NE trade winds, creating warm humid air and reducing upwelling of cold waters resulting in dramatic perturbations to maritime and terrestrial flora and fauna [1,2]. El Ni?o events are differentiated by intensity and duration, or a combination of both. Particularly extreme or intense events as in 1983/84, or 1997/98 are referred to as Mega El Ni?o that appear to have their origins 5800 years ago [3-5]. Such climatic and oceanographic perturbations have dramatic impacts upon human adaptation and sociocultural development. These climatic and oceanographic alterations create a reduction of upwelling cold waters along the west coast of South America. These climatic changes result in dramatic perturbations to maritime and terrestrial flora and fauna and, consequently, human adaptation. El Ni?o events are differentiated by their intensity and duration, or a combination of both [6-8]. Particularly extreme or intense events as in 1983/84, or 1997/98 are referred to as Mega El Ni?o which appear to have their origins 5800 years ago [3]. There is geological and archaeological evidence based upon the frequency of species of shellfish, to indicate they increased in frequency and duration between 5800 and 3200 BP and decreased in frequency between 3200-2800 BP.