Sampling Galapagos corals for SST trend reconstruction

University Of Arizona, Tucson AZ

Investigators

Abstract

With this award the PI will sample living corals in the Galapagos islands that face a threat of serious damage in the next several months, a period during which a moderate to strong El Nino episode is predicted by most dynamical model forecasts of ENSO. Previous El Nino episodes have caused upwards of 95% coral mortality in the region, and the reef identified for sampling in this project may be the only living Porites (massive coral) of century-plus age remaining in the Galapagos archipelago. Based on the measured sizes and growth rates, the PIs predict that these corals preserve an annually-resolved record of sea surface temperature over the past one to three centuries, which represents a substantial extension of existing coral record length in the region. Records from the new cores will provide a critical piece of the puzzle in determining how the equatorial gradient of SST has evolved over the past century and will shed light on the mechanisms by which ENSO responds to anthropogenic climate forcing. The field program will involve a PhD student from the University of Arizona and a graduate student from Ecuador.