• DOI:10.1126/SCIENCE.283.5401.516
• Corpus ID: 13714632

An ;15,000-Year Record of El Nino—Driven Alluviation in Southwestern Ecuador

@article{Rodbell1999AnR,
  title={An ;15,000-Year Record of El Nino—Driven Alluviation in Southwestern Ecuador},
  author={Donald T. Rodbell and Geoffrey O. Seltzer and David M. Anderson and Mark B. Abbott and David B. Enfield and Jeremy H. Newman},
  journal={Science},
  year={1999},
  volume={283},
  pages={516-520}
}

• D. Rodbell, Geoffrey O. Seltzer, +3 authors Jeremy H. Newman
• Published 22 January 1999
• Environmental Science
• Science

Debris flows have deposited inorganic laminae in an alpine lake that is 75 kilometers east of the Pacific Ocean, in Ecuador. These storm-induced events were dated by radiocarbon, and the age of laminae that are less than 200 years old matches the historic record of El Nino events. From about 15,000 to about 7000 calendar years before the present, the periodicity of clastic deposition is greater than or equal to 15 years; thereafter, there is a progressive increase in frequency to periodicities of 2 to 8.5 years. This is the modern El Nino periodicity, which was established about 5000 calendar years before the present. This may reflect the onset of a steeper zonal sea surface temperature gradient, which was driven by enhanced trade winds.