New Paper Update: Subannual D47 reconstructs Last Interglacial climate and d18Owater variability in Bermuda

Sliced Cittarium pica, showing location of high resolution d18Ocarb drilling (green) and seasonally-targetted D47 drilling (red)

Jade’s first paper is now published in the journal Paleooceanography and Paleoclimatology. Congrats Jade! In this work, Jade analyzed fossil shells of the species Cittarium pica, a large gastropod known as the Indian Top Shell. She sampled these shells along their spiral growth direction to reconstruct ocean temperatures and oxygen isotopic compositions (seawater d18O) throughout a few years of their lifetime. These shells date from the Last Interglacial (LIG) interval (~125,000 years ago), a period when global climate was 1-2 degrees warmer and sea levels were 6-9m higher. Despite overall global warmth, we found Bermuda was actually slightly cooler during the LIG, consistent with other records from the region. We also found unexpectedly high variability in d18Oseawater, which we linked to freshwater discharge from an underground aquifer into the near coastal areas.