Presenter: Nina Whitney (Woods Hole Oceanographic Institution)

Description:
The Mid-Atlantic Bight Cold Pool is a region of seasonal, cold (<10°C), near-bottom water that forms along the Mid-Atlantic Bight in the western North Atlantic during the spring and summer months, primarily as a result of remnant winter surface waters as well as northerly-derived waters transported into the region. The colder water at this low-latitude region provides critical habitat for species primarily found at higher latitudes, such as yellowtail flounder and ocean quahogs. Recently, some evidence suggests that the Cold Pool has begun to degrade, raising concerns about the future of the species that rely on the presence of this cold water. However, the lack of long-term, instrumental records limits our understanding of decadal- to centennial-scale temperature trends in the region. Here we present preliminary, high-resolution oxygen isotope data from absolutely-dated Arctica islandica (ocean quahog) shells along with high-resolution ocean model simulations in order to investigate the evolution of Cold Pool temperatures through time. Shells were collected from southeast of Long Island at ~45m depth, near the center of the Cold Pool, and span the last ~170 years. We present seasonally-resolved oxygen isotope data to identify changes in seasonality along with changes in annual average temperature over the last two centuries in this region. We employ nested 1/20° ocean model simulations from the VIKING20X model to interpret inferred temperature variability at the heart of the Cold Pool, derived from our geochemical records, in the context of larger changes in the Cold Pool and broader Northwest Atlantic region.