RV Nathaniel B. Palmer NBP2401 (ANT, GP17)
Cruise summary report
| Cruise Info. | |
| Ship name (ship code) | RV Nathaniel B. Palmer (3206) |
| Cruise identifier | NBP2401 (ANT, GP17) |
| Cruise period | 2023-11-29 — 2024-01-28 |
| Status | Completed |
| Port of departure | Punta Arenas, Chile |
| Port of return | Lyttelton, New Zealand |
| Purpose | Research |
| Objectives | This oceanographic expedition was focused on water-column sampling and hydrographic measurements at stations located over the continental shelf of the Amundsen Sea, as well as several deep-ocean stations located north of the Antarctic shelf break.
Given the importance of the Amundsen Sea for glacial meltwater discharge and associated inputs and mobilization of TEIs, the potential impacts of these inputs, and the rapid pace of environmental changes in this region, it was selected as the focus of the US GEOTRACES GP17-ANT expedition, to complement the open-ocean GP17-OCE cruise. With support from the NSF Chemical Oceanography and Antarctic Oceans and Atmosphere Programs, a cruise management award to Sedwick, Lam, Sherrell and Anderson allowed for the planning and implementation of the 60-day GP17-ANT expedition aboard RVIB Nathaniel B. Palmer, which provided a platform for the collection of samples for 23 individual science projects that together encompass measurements of nearly all of the GEOTRACES key TEIs. In total, the GP17-ANT cruise sampled 21 stations over the Amundsen Sea continental shelf, 3 stations over the continental slope, and 3 off-shelf stations, including one deep-ocean station that provides a crossover with the preceding GP17-OCE cruise. All of these GP17-ANT stations included collection of samples with a near-surface towfish, a conventional CTD-rosette, a tracemetal clean CTD-rosette, and McLane in situ pumps. Additional sampling activities included collection of aerosols, precipitation, sea ice and snow, as well as sediment cores for pore-fluid extraction, and high-volume pumped seawater samples for radium isotopes and beryllium-7. Although most of the GP17-ANT science goals were achieved, large expanses of heavy sea ice surrounding the Amundsen Sea Polynya prevented access to several of our planned sampling locations, including stations near the Thwaites Ice Shelf, in Pine Island Bay, and over the eastern portion of the outer Amundsen Sea shelf. Nevertheless, the cruise provided us with exciting opportunities to collect samples from stations adjacent to the Dotson and Getz Ice Shelves, as well as on- and off-shelf stations that were impacted by melting sea ice, polynya stations where phytoplankton biomass was extraordinarily high, and a station adjacent to fast ice with near-zero chlorophyll fluorescence in the water column. |
| Chief scientist | Peter N Sedwick (Old Dominion University Department of Ocean, Earth and Atmospheric Sciences), Phoebe J Lam (University of California Santa Cruz Institute of Marine Sciences), Robert Sherrell (Rutgers University Institute of Marine and Coastal Sciences) |
| Project | GEOTRACES -Trace elements and their isotopes in the water column |
| Cruise report |  (6.11 MB) |
| Ocean/sea areas | |
| General | Southern Ocean Unknown |
| Specific | Amundsen Sea |
| Track charts | (0.11 MB) |
