Paleotemperatures have been widely deduced from skeletal 18O/16O ratios, but these are also dependent on salinity. Without an independent measure of salinity, 18O/16O ratios cannot provide accurate data on past temperature and climate. We grew marine mollusks (bivalves) in the field while real-time data on local seawater temperature and chemistry (Mg, Ca, δ18O, and salinity) were gathered. Here we show that for Mytilus trossulus, skeletal Mg/Ca ratios provide an accurate measure of temperature and that weekly sea-surface temperatures may be estimated with an apparent accuracy of approximately ± 1.5 °C. Thus, with analyses of both Mg/Ca and δ18O from the same specimen, it is possible to determine seawater temperature and δ18O.

This content is PDF only. Please click on the PDF icon to access.

First Page Preview

First page PDF preview
You do not currently have access to this article.