On December 1, 2011, the West Antarctic Ice Sheet (WAIS) Divide ice core project, funded by the National Science Foundation (NSF), reached its final depth of 3405 meters (11,171 feet; over 2 miles), recovering the longest U.S. ice core to date from the polar regions. The WAIS Divide ice core was recovered at a field camp in the center of West Antarctica, 1,040 kilometers (650 miles) from the geographic South Pole, where the ice is more than 3,460 meters (two miles) thick. The drill site is characterized by a combination of moderate ice accumulation rate, thick ice, and other characteristics that preserve detailed information on past environmental conditions during the last 68,000 years. The drilling of the ice core ceased 50 meters (164 feet) above the contact between the ice and the underlying rock, to avoid contaminating a possible water layer at the ice-rock contact. In the WAIS Divide ice core, each of the past 30,000 years of snowfall can be identified in individual layers of ice, with lower temporal resolution records extending to 68,000 years before present. The WAIS Divide ice core has provided the first Southern Hemisphere climate and greenhouse gas records of comparable time resolution and duration to the Greenland deep ice cores, enabling detailed comparison of environmental conditions between the northern and southern hemispheres, and the study of greenhouse gas concentrations in the paleo-atmosphere, with a greater level of detail than previously possible.
There is one 12.2 cm diameter deep (3405 meters long) ice core (WDC06A) and several shallow smaller-diameter cores available in the ICF inventory.
REPLICATE CORES
In December, 2012, the researchers re-entered the deep borehole and successfully drilled through the wall of the 3405-meter deep parent hole and collected a total of 285 meters of additional "replicate" core (10.8 cm diameter) from five of the most interesting time periods in the WAIS Divide climate record. Deviation #1 corresponds to AIM8 and the Laschamp Event. Deviation #2 corresponds to the 18 ka event. Deviation #3 corresponds to the Bølling-Allerød event. Deviation #4 corresponds to the Younger Dryas event. Deviation #5 corresponds (again) to the 18 ka event.
| Deviation # | Coring Start Depth (m) | Full Diameter By (m) | Coring End Depth (m) |
|---|---|---|---|
| 1 | 3001.55 | 3006.16 | 3100.26 |
| 2 | 2416.70 | 2420.02 | 2469.49 |
| 3 | 2221.00 | 2226.16 | 2290.80 |
| 4 | 1952.00 | 1956.90 | 2000.20 |
| 5 | 2414.50 | 2420.02 | 2428.74 |
WAIS Divide ice core datasets are archived at the following data centers.
- WD2014: Timescale for WAIS Divide Core 2006 A (WDC-06A)
- WAIS Divide ice core data archived at the USAP Data Center
- National Snow and Ice Data Center
- WAIS Divide ice core data archived at NOAA
- See the WAIS Divide publications webpage for a list of WAIS Divide publications.