Geochemical time series from remote Pacific atolls have provided long records of climate variability that extend into the pre-industrial era. Recent studies document a wide range of geochemical variability in corals growing on the same reef, ostensibly of the same genus. Deciphering which fraction of coral geochemistry variations are driven by changes in physical environment versus physiological differences between corals is key to constructing more robust records of past climate variability. We propose to probe the linkages between coral geochemistry and coral genomics using a suite of existing coral samples - both skeletal material and tissue samples - from a well-characterized site in the central equatorial Pacific that has been well-instrumented for the last 3 years. This project will blend approaches from carbonate geochemistry, ecology, genomics, and bioinformatics in the first study of its kind.