Extending the Instrumental Record of Ocean-Atmosphere Variability into the Last Interglacial Using Tropical Corals

The interaction of warm tropical ocean surface waters with the overlying atmosphere on seasonal, interannual, and decadal timescales is the source of climate extremes throughout the tropics and beyond. Tropical cyclones, heatwaves, flash floods, droughts, and El Nino have severe effects on ecosystems and societies globally. Projecting their amplitude and frequency changes in a warming climate requires knowledge of how the tropical ocean-atmosphere system operated in the past. Tropical shallow-water corals have great potential for extending the short and rather sparse instrumental record of sea surface observations at monthly resolution. Coral records deliver quantitative information about the fluctuations of sea surface temperature and hydrology on seasonal, interannual, and decadal timescales, with precise chronology. They provide a paleo-observational constraint on climate model simulations of past and future tropical ocean-atmosphere variability. This article highlights selected recent achievements in coral-based reconstructions of surface ocean conditions during recent centuries, the Holocene, the last deglaciation, and the last interglacial period. Future work combining ultrahigh-resolution coral reconstructions, novel analytical techniques, advanced statistical methods, and Earth system modeling will contribute to improved projections of tropical marine climate variability and the fates of coral reef ecosystems.