The study of El Nino climate changes is hampered by our short historical record of their occurrence. Fortunately the changes in ocean chemistry and temperature that are produced by El Nino are recorded in the chemistry of living corals. And since corals secrete annual growth bands, the record of their changing chemistry can provide us with the means to reconstruct the history of El Nino occurrence back through the life span of coral (up to about 300 years). The goal of this research program is to reconstruct this paleoclimate history from banded corals in the western Pacific (Tarawa Is.) and eastern Pacific (Galapagos Is.). The project involves field programs to each island to sample the coral, followed by laboratory analyses of the trace element and stable isotopic chemistry of the coral growth bands. This study will contribute to our understanding of the history, frequency of occurrence, and climatic significance of El Nino phenomena.
