Calibration of modern coral climate signals to ensure accuracy of paleoclimate determinations in Anegada, British Virgin Islands
Ocean Sciences Meeting, Honolulu, Hawaii
Three modern Diploria strigosa corals from Anegada, British Virgin Islands were analyzed for Sr/Ca ratios over their lifetime to create a modern calibration between Sr/Ca and sea surface temperature (SST) for use in climate reconstructions of subfossil coral specimens from the same site. Average mean Sr/Ca among the three corals was 9.03 mmol/mol with a range of 0.15 mmol/mol. The combined Sr/Ca-SST relationship for the three corals using ordinary least squares regression was -0.047 ±0.001 mmol/mol/°C with a standard error of regression of ±0.6°C using the monthly Sr/Ca from corals and gridded temperature from the ERSST 3b data set (Smith et al., 2008), which agrees with previous Sr/Ca-temperature calibrations using this species. The Sr/Ca-SST relationship for the three corals using reduced major axis regression was -0.058 ±0.001 mmol/mol/°C with a standard error of regression of ±0.4°C, whereas the Sr/Ca-SST relationship was -0.107 ±0.004 mmol/mol/°C with a standard error of regression of ±0.2°C based on the monthly anomalies. This calibration informs further work reconstructing Medieval climate data from subfossil corals at this site.