Center for OLDest Ice Exploration (COLDEX)
Cores drilled through the Antarctic ice sheet provide a remarkable window on the evolution of Earth’s climate and unique samples of the ancient atmosphere. The clear link between greenhouse gases and climate revealed by ice cores underpins much of the scientific understanding of climate change. Unfortunately, the existing data do not extend far enough back in time to reveal key features of climates warmer than today. COLDEX, the Center for Oldest Ice Exploration, will solve this problem by exploring Antarctica for sites to collect the oldest possible record of past climate recorded in the ice sheet.
This component of COLDEX will recover a suite of shallow (16 x < 200 m) ice cores from the Allan Hills and other Antarctic Blue Ice Areas (BIAs) that contribute towards our understanding of how Earth's climate system operated during warmer periods in the past and why the periodicity of glacial cycles lengthened from 40,000 to 100,000 years approximately 1 million years ago. These ice cores will be dated using a newly developed array of dating methods to establish a preliminary depth/age time scale. Subsections of the cores will be imaged and analyzed for stratigraphic orientation using ECM and a suite paleoclimate properties (e.g. CO2, CH4, O2/N2/Ar, water isotopes, etc.).
- Point of Contact:
Ed Brook, Oregon State University.
- Schedule: 11/01/2024 - 1/31/2025
- Equipment: Blue Ice Drill, Eclipse Drill, IDDO Hand Auger, Sidewinder
Collaborative Research: Constraining West Antarctic Ice Sheet Elevation during the last Interglacial
This project aims to collect a novel dataset to determine how the West Antarctic Ice Sheet (WAIS) responded to a warmer climate during the last interglacial period (~125,000 years ago) by reconstructing the glacial history at the Mt. Waesche volcano in Marie Byrd Land, Antarctica. Reconstructing WAIS geometry when the ice sheet was smaller than present is difficult, and data are lacking because the evidence lies beneath the present ice sheet. The scientists will use the Eclipse Drill and Winkie Drill to drill through the ice sheet and recover bedrock that can be analyzed for its surface exposure history to help determine when the surface became overridden by the ice sheet. The research will constrain the WAIS's past maximum and minimum spatial extent during the last glacial-interglacial cycle.
- Point of Contact:
Matthew Zimmerer, New Mexico Institute of Mining and Technology. Seth Campbell, University of Maine. Jerry Mitrovica, Harvard University.
- Schedule: 11/1/2024 - 1/1/2025 (estimated)
- Equipment: Winkie Drill, Eclipse Drill
Collaborative Research: EAGER: Dating Glacier Retreat and Readvance near Mount Waesche, West Antarctica
This project aims to obtain glaciological and geological data on the past extent of the West Antarctic Ice Sheet. A key location for determining this ice extent is Mount Waesche, a volcano that rises above the ice surface near the dome of the ice sheet. Previous field expeditions to the Mt. Waesche volcano in Marie Byrd Land, Antarctica, used ground-penetrating radar to map the area's sub-ice topography and internal glacial layering. These radar profiles revealed discontinuities within the ice that represent lower ice levels that may have occurred in the past. This project aims to enhance the team’s rock core drilling program at Mount Waesche by dating the discontinuities in the ice. Using the Eclipse Drill, the team will collect ice cores from above and below the discontinuities to constrain the ages of the discontinuities. Isotopic and tephra analysis will be used to provide age constraints on the ice cores. These data will be correlated with other, well-dated West Antarctic ice cores to obtain a local chronology and date the discontinuities. This exploratory work aims to provide data that complement the results from subglacial rock cores to constrain surface-elevation change better, including both retreat and readvance, since the last interglacial.
- Point of Contact:
Seth Campbell, University of Maine.
- Schedule: 11/15/2024 - 01/31/2025 (estimated)
- Equipment: Eclipse Drill, Chipmunk Drill
NSFGEO-NERC: Investigating the Direct Influence of Meltwater on Antarctic Ice Sheet Dynamics
This project aims to examine the response of the flow of an Antarctic Peninsula outlet glacier (Flask Glacier) to surface meltwater. Satellite observations suggest that Antarctic Peninsula outlet glaciers speed up during surface melt events. The researchers will make field observations of surface melting, ice dynamics, and surface conditions on Flask Glacier to investigate if Antarctic Peninsula outlet glaciers speed up during surface melt events. The researchers will use an IDDO Hand Auger to drill several shallow firn cores. The firn cores will be used to constrain firn stratigraphy to help determine how temporal changes in near-surface water content affect satellite-based velocity measurements.
- Point of Contact:
Jonathan Kingslake, Columbia University.
- Schedule: 11/15/2024 - 01/31/2025 (estimated)
- Equipment: IDDO Hand Auger
Collaborative Research: Using New Ice Cores from Dome C to Test the Assumption of a Constant Galactic Cosmic Ray Flux and Improve Understanding of the Holocene Methane Budget
This project will obtain new ice cores in Antarctica in collaboration with the French Polar Institute. The project aims to improve our understanding of the history of cosmic rays originating from outside our solar system. Records of atmospherically produced cosmogenic nuclides have been used to reconstruct past solar activity and solar irradiance. Cosmogenic nuclides produced in surface rock are widely used in studies of past ice dynamics and extent. All these studies generally assume that the galactic cosmic ray flux at Earth is constant in time, but this is uncertain by 30% or more. Using the 4-Inch Drill, the researchers will drill two ~300-meter-long ice cores from the Dome C region of Antarctica. This project will use measurements of in situ cosmogenic carbon-14 of carbon monoxide (14CO) in the newly drilled ice cores to test the assumption of constant galactic cosmic ray flux. The researchers will also measure carbon-14 of methane (14CH4) to help improve our understanding of the Holocene methane budget.
- Point of Contact:
Vas Petrenko, University of Rochester.
- Schedule: 11/17/2024 – 02/02/2025 (estimated)
- Equipment: 4-Inch Drill