News & Events

Grad student talk - Testing for orbital and solar forcing of the ENSO system during the Holocene

Thursday, October 03, 2013, 4:30PM - 5:30PM

Speaker

Hannah Grist

Location:

RL-1 room 269

The El Niño-Southern Oscillation (ENSO) system has been shown to vary on both orbital and millennial timescales during the late Quaternary. Proxy records of Mg/Ca-derived sea surface temperature (SST) and climate models show an increased temperature gradient across the Pacific corresponding to a more La Niña-like state during the early-mid-Holocene. Previous measurements on Globigerina bulloides from the Soledad Basin off the coast of Baja California Sur (Marchitto et al., 2010) confirm orbital scale cooling during the early-mid-Holocene (10-4 ka). Millennial scale cold intervals between 11-7 ka correspond to solar maxima suggesting that the ocean dynamical thermostat also operates on millennial timescales. This study compares Mg/Ca measurements from two other species to enhance our understanding of orbital and solar forcing of the ENSO system.