Using Recorded and Proxy Sea Surface Temperature and Sea Surface Salinity to Estimate
The Aragonite Saturation State, Correlations with Coral Calcification Rates
Venti, A aventi@rsmas.miami.edu
Marine and Atmospheric Chemistry,
University of Miami,
Rosenstiel School of Marine and Atmospheric Science,
Miami, FL, United States
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This is the first study to use proxy sea surface salinity and sea surface temperature values,
obtained from Scleractinian corals, to estimate regional aragonite saturation states. It is
important to understand how Ωarag values have changed in recent decades as SST and
pCO2 values have increased, but measurements of Ωarag are limited in space and time. The
method presented here allows for Ωarag to be estimated throughout the history of any coral
core record and may provide insight into how Ωarag has changed both before and after
major anthropogenic influxes of CO2. There were three primary objectives of this study:
1) to determine whether annual average Ωarag could be estimated accurately with proxy
SSS, and SST data obtained from elemental and isotopic analysis of coral core samples,
2) to test for significant declines in annual average Ωarag over the past 95 years, and 3) to
test for significant correlation between annual changes in Ωarag and annual coral
calcification rates, thereby assessing the implications of climate change on scleractinian
coral growth. The Ωarag calculated using proxy data, obtained from isotopic and elemental
analysis of annual deposits from coral core samples, are compared with Ωarag calculated
using the regional recoded data from. We find statistical significance between recorded
and proxy calculated Ωarag in 4 of the 6 core records. Statistically significant declines in
annual average Ωarag were found for recorded environmental data from Curaçao, and for
proxy environmental data from 4 of the 6 core samples. These results suggest that proxy
SSS and SST data can be used to predict Ωarag, and that Ωarag, is significantly declining.
This study also provides new insight in understanding the relationship between Ωarag and
coral calcification rates by testing for significant correlation between these two
parameters, which was found in 5 of the 11 cores analyzed. This suggests that
calcification rates will continue to decline as aragonite saturation states decline.