A multinational research team has completed a 55-day scientific mission to the Cook Ice Shelf marine region in East Antarctica aboard the CSIRO research vessel (RV) Investigator. Led by scientists from the University of Tasmania's Institute for Marine and Antarctic Studies (IMAS), the expedition traveled more than 12,000 kilometers to collect extensive data, samples, and specimens. The research aims to understand how the Antarctic environment has responded to past warming events and to inform predictions for its future under climate change.
Mission Overview and Objectives
The expedition, known as the COOKIES voyage, focused on the marine area off the Cook Ice Shelf in East Antarctica. This region has been previously unstudied in various key aspects, including oceanographic, bathymetric, biological, and paleo-data.
The primary objectives included investigating the region's ice-sheet stability, ocean evolution, and its impact on marine ecosystem functions over the last one million years. The data gathered will establish long-term and contemporary baselines for understanding climate change impacts in this part of Australia's Antarctic Territory.
Recent modeling suggests the Cook Ice Shelf is susceptible to climate change, with projections indicating ice mass loss over the next 200 years. The research contributes knowledge to the East Antarctic Marine Ice Sheet Instability (EA-MISI) initiative, part of the EU-Polarnet project, which enhances international polar research collaboration.
Comprehensive Data Collection Activities
During the voyage, the multinational team of 58 researchers and crew utilized RV Investigator's scientific equipment to conduct a range of data collection activities from the ocean surface to the seabed.
Seabed Mapping and Sediment Cores- High-resolution seabed mapping (bathymetry) and subsurface sediment layers were conducted using the RV Investigator's multibeam echosounders. This mapping guided the selection of optimal locations for seabed sediment sampling.
- Sediment cores were retrieved using the vessel's piston coring system. These cores, which can span hundreds of thousands to millions of years, function as archives of global change, containing ancient DNA, microfossils, rocks, and chemical indicators.
- A record-setting 20.5-meter sediment core was collected. In total, the voyage returned with over 10,000 sediment samples for laboratory analysis of ancient DNA, microfossils, and geochemistry.
- Underway sampling systems continuously collected surface seawater samples for analysis of plankton, environmental DNA (eDNA), microbes, and diatoms. Over 130 water samples were gathered to track shifts in marine life and chemistry across thousands of kilometers.
- CTD (conductivity, temperature, and depth) instruments were deployed to trace the ocean's biological, chemical, and oceanographic structure from the surface to the seabed. These measurements provide insights into water layer interactions and their influence on marine life. Water collected from Niskin bottles measured nutrients present in marine ecosystems.
- A specialized trace metal rosette was deployed to collect water samples for trace metal analysis. Trace metals like iron, zinc, manganese, and copper are essential for marine life and can be limiting factors in phytoplankton growth.
- The Deep Towed Camera surveyed benthic (seafloor) ecosystems, capturing over 10,000 still images and video footage for biodiversity analysis.
- Benthic sled sampling operations collected approximately 400 marine organisms for identification, study, and DNA analysis. These biological surveys, combined with ocean data, are intended to provide insights into the resilience of Antarctic ecosystems.
- An AI camera system named 'Jonathan' was used to count seabirds during the voyage.
Future Analysis and Global Impact
The collected samples and data are expected to undergo years of laboratory analysis by researchers and students. This research will contribute to scientific knowledge about Antarctic ecosystems, climate change, and ocean processes.
Andrew Martini, Program Director with the CSIRO Marine National Facility, stated that the voyages to Antarctica provide access to an environment that offers insights for the global scientific community. The knowledge gained is anticipated to contribute to a better understanding of changes affecting oceans, climate, and life on Earth.
Dr. Linda Armbrecht, Chief Scientist of the COOKIES voyage and IMAS researcher, noted that the knowledge gathered will inform international scientific planning for the conservation and management of Antarctica.
Collaborations and Support
This research was supported by:
- A grant of sea time on RV Investigator from the CSIRO Marine National Facility.
- Contributions from the Australian Centre of Excellence in Antarctic Science (ACEAS).
- The Antarctic Science Foundation (ASF).
- Securing Antarctica's Environmental Future (SAEF).