NOAA/WDS Paleoclimatology - Urvina Bay - Radiocarbon Data

Radiocarbon (14C) content of surface waters inferred from a coral record from the Galápagos Islands increased abruptly during the upwelling season (July through September) after the El Niño event of 1976. Sea-surface temperatures (SSTs) associated with the upwelling season also shifted after 1976. The synchroneity of the shift in both 14C and SST implies that the vertical thermal structure of the eastern tropical Pacific changed in 1976. This change may be responsible for the increase in frequency and intensity of El Niño events since 1976.