Collaborative Research: A Holocene History of the El Nino/Southern Oscillation, Solar Variability, and the Central American Monsoon from Speleothem Calcite

University Of Massachusetts Amherst, Amherst MA

Investigators

Abstract

This award will test whether tropical Holocene climate was subject to decadal to millennial scale changes in rainfall amount associated with the El Nino/Southern Oscillation (ENSO), which is the largest source of interannual climate variability on the isthmus of Panama, and/or solar irradiance changes. Isotopic paleoclimate proxy records from Central American stalagmites covering the Holocene will be generated and compared with proxy and meteorological records of ENSO, solar irradiance, and temperature. The primary objective of this research is to document Holocene ENSO and rainfall variability. The records will be produced using mass spectrometric methods to analyze the stable isotopes of oxygen, deuterium, and carbon in water and carbonate, radiogenic U-series isotopes to determine stalagmite chronology, and annual layer thickness counts where appropriate. This research is original and pertinent and should make important contributions to understanding of ENSO variability through the Holocene. Data developed during this study should be useful for comparisons and correlations to other tropical paleoclimate records.