Overview
The U.S. GEOTRACES GP17-ANT expedition departed Punta Arenas, Chile on November 29th, 2023 and arrived in Lyttelton, New Zealand on January 28th, 2024. The cruise took place in the Amundsen Sea aboard the R/V Nathaniel B. Palmer (cruise NBP24-01) with a team of 35 scientists lead by Peter Sedwick (Old Dominion University), Phoebe Lam (University of California, Santa Cruz) and Robert Sherrell (Rutgers University). GP17 was planned as a two-leg expedition, with its first leg (GP17-OCE) as a southward extension of the 2018 GP15 Alaska-Tahiti expedition and this second leg (GP17-ANT) into coastal and shelf waters of Antarctica's Amundsen Sea.
The almost two months cruise was largely successful in achieving its science goals, with 21 stations over the Amundsen Sea continental shelf, 3 stations over the continental slope and 3 off-shelf stations, including one deep-ocean station as a crossover with the preceding GP17-OCE cruise. All stations included collections of samples with a near-surface towfish, a conventional CTD-rosette, a trace-metal clean CTD-rosette, and McLane in-situ pumps. Additional sampling activities included the collection of aerosols, precipitation, sea ice an snow as well as sediment cores for pore-fluid extraction and high-volume pumped seawater samples for radium isotopes and beryllium-7. The heavy sea ice cover prevented access to a number of planned stations including the Thwaites Ice Shelf, Pine Island Bay and the eastern portion of the outer Amundsen Sea shelf. Nonetheless, samples were collected from stations adjacent to the Dotson and Getz Ice Shelves, as well as on- and off-shelf stations 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. With support from the U.S. National Science Foundation samples were collected from 23 separate science projects, which together encompass measurements of nearly all of the GEOTRACES key trace elements and isotopes.
Dates: 6-8 May, 2020
Information: This online planning meeting brought together researchers who expected to submit proposals for one or both of the GP17 expeditions. Link to the workshop announcement.
Contacts:
Greg Cutter [[email protected]], or
Ben Twining [[email protected]]
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U.S. GEOTRACES GP17-OCE Pre-Cruise Planning Meeting
Dates: 17-18 March, 2022
Location: Old Dominion University, Norfolk, Virginia. Venue website and map.
Objective: Coordinate the scientific objectives and supporting logistics for the research cruise from Tahiti to Chile (GP17-OCE) planned for December 2022-January 2023. The GP17-OCE transect will include a nearly meridional section from 20°S to 67°S, a zonal section along 67°S from 135° to 100°W, and a margin section from 67°S 100°W to the Chilean margin. Cruise leaders: Ben Twining, Jessica Fitzsimmons and Greg Cutter.
Links:
-> Agenda
-> Section Goals - Introductory Presentation
- U.S. GEOTRACES GP17-ANT Pre-Cruise Planning Meeting
Dates: 13-14 March, 2023
Location: Old Dominion University, Norfolk, Virginia. Venue website and map.
Objective: The meeting was held at Old Dominion University with most of the ~70 participants in person and a few online. The main objective of the meeting was to advance the planning of the GP17-ANT cruise logistics. Since this cruise will take place on the RVIB N.B. Palmer, rather than a UNOLS vessel, as was the case for previous GEOTRACES cruises, Antarctic Support Contractors (ASC) will play a major role in supporting the cruise logistics. Therefore, one of the objectives of the meeting was to familiarize participants with the support provided by ASC. The agenda for the meeting is attached (pdf file).
- GP17 Statements of Interest: Links to all the submitted statements of interest to aid in the management proposal preparation for each cruise.
- Collection of slides illustrating the oceanographic features that motivate this cruise:
-> GP17-ANT
Cruise Information
- Cruise Report (PDF format)
- Cruise Field Notes: journalist Sofia Moutinho joined and documented the GP17-ANT expedition. You can access to her 2024 Eos article Confined at sea at the end of the world, and to her series of audio/transcripts episodes published by Scientific American.
Link to GP17-ANT related peer-reviewed papers database.
Funding and Support
