| Summary: | Gordon Research Seminar (GRS) and Gordon Research Conference (GRC), RUTGERS The State University of New Jersey.-- 1 page, 6 figures Changes in the supply of preformed nutrients to the low-latitude thermocline have been implicated as a possible driver of glacial-interglacial CO2variations1. Old, nutrient-rich deep waters are upwelled in the Southern Ocean, advected north and modifiedby biological production, and subsequently subducted to form, Subantarctic Mode Waters (SAMW)and Antarctic Intermediate Waters (AAIW; Fig. 1). These waters supply the low-latitude thermocline with nutrients and may impact biological productivity and the sequestration of atmospheric CO2.Fossil deep-sea corals, Desmophyllum dianthus, around New Zealand offer a unique opportunity to reconstruct the pre-formed nutrient inventory of SAMW and AAIW as they exit the Southern Ocean (Fig. 1). Paleoproxies for nutrients (P/Ca, Ba/Ca)and carbonate ion concentrations (U/Ca) have been field-calibrated in this species2, but with uncertainties. We seek to improve calibrations of these proxies through culturing experiments in controlled seawater conditions, and by refining micromilling and laser-ablation ICPMS (LA-ICPMS) methodologies. Additionally, we are exploring the use of Cd/Ca as an alternative phosphate proxy and Mg/Li as a proxy for temperature Peer Reviewed
|
|---|