Massive hermatypic corals are one of the most excellent archives for reconstructing paleoclimatic and paleoceanographic changes because they commonly live in shallow tropical and subtropical oceans, grow at a rapid rate, and contain a remarkable array of geochemical tracers within their skeletons. In particular, oxygen isotopic composition and Sr/Ca ratio of coral skeletons have been used as proxies for past thermal and hydrological variations in sea surface conditions. Recent investigations on geochemical records of modern long coral cores provide continuous time series of sea surface temperature and salinity in many tropical regions, which document climatic variability on interannual and decadal to multidecadal timescales (El Nino/ Southern Oscillation, Indian Ocean Dipole mode, and Inter-decadal Pacific Oscillation), volcanic eruptions, and global warming. However, high-resolution paleoclimatic records of coral skeletons over the last several centuries are spatially limited and the mechanisms causing the climatic variability remain unclear at present. High-fidelity paleoclimatology should be progressed in order to expand our knowledge on the nature and causes of global climatic changes.
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