Holocene history of ENSO variance and asymmetry in the eastern tropical Pacific

Science  07 Aug 2014:
DOI: 10.1126/science.1252220

You are currently viewing the abstract.

View Full Text


Understanding the response of the El Niño-Southern Oscillation (ENSO) to global warming requires quantitative data on ENSO under different climate regimes. Here, we present a reconstruction of ENSO in the eastern tropical Pacific spanning the last 10 thousand years (ka) derived from oxygen isotopes in fossil mollusk shells from Peru. We find that ENSO variance was close to the modern level in the early Holocene and severely damped ~4-5 ka. In addition, ENSO variability was skewed toward cold events along coastal Peru 6.7-7.5 ka owing to a shift of warm anomalies toward the Central Pacific. The modern ENSO regime was established ~3-4.5 ka. We conclude that ENSO was sensitive to changes in climate boundary conditions during the Holocene, including, but not limited to insolation.

View Full Text