δ¹⁸O

Distribution of annual mean tropical SSTs an approximater locations of current coral paleoclimate research

Because the δ¹⁸O composition of coral skeletons is a function of both SST and seawater δ¹⁸O (δ¹⁸O) (Weber and Woodhead, 1972), it is generally difficult to separate the effects of both variables using coral δ¹⁸O alone. However, using both δ¹⁸O and Sr/Ca records, it is possible to separate the different effects of δ¹⁸O_SW and SST in a coral δ¹⁸O time series (McCulloch et al., 1994; Gagan et al., 1998; 2000).

Annual mean coral d18O records for several sites in the Pacific and Indian Oceans.

The stable oxygen isotopic composition of seawater (δ¹⁸O_SW) is of climatic importance because it is closely related to the balance between precipitation and evaporation, and so its reconstruction could yield important information about past changes in hydrological balance and oceanographic circulation.