Paper No. 174-3
Presentation Time: 2:05 PM
EXTRACTING TEMPERATURES FROM FORAMINIFERAL δ18O: MODEL-DATA APPROACHES AND A NEW ONLINE TOOL
Oxygen isotope measurements (δ18O) from the shells of foraminifera are one of the most data-dense and high-resolution proxy archives for reconstructing marine temperatures and climate transitions, but their interpretation has historically been complicated by diagenetic overprinting and uncertainties surrounding the δ18O of the seawater in which the shells grew. Seawater δ18O is both spatially and temporally variable and is strongly influenced by both global ice volume and local climate-dependent hydrology. We review recent advances in oxygen-isotope temperature reconstructions and demonstrate how coupling δ18O measurements to isotope-enabled general climate models (GCMs) can yield coherent δ18O-based sea-surface temperatures which are consistent with other temperature proxies, even in traditionally difficult cases such as the Early Eocene. We present a new online tool that automates both traditional and novel δ18O-temperature conversion methods.