Drilling Into the Past

Aerial view of the Greenland ice sheet. David Fisher's team will be drilling in northwest Greenland.

One thousand years ago, Vikings walked on Greenland. Archaeology tells us that. But who or what was there 130,000 years before them, and how can we find out? Over the course of the International Polar Year, David Fisher, head of glaciology at Natural Resources Canada (NRCan), will be leading a Canadian team seeking answers to these questions.

David and some of his NRCan colleagues will be working with Danish scientists to obtain and study an ice core from the Greenland ice sheet.

“Ice cores have layers,” says David, “and in those layers climate history is recorded.”

This record, or climate archive, makes it possible for glaciologists to determine the climatic conditions of the Earth at the time the ice was formed.

The Greenland ice sheet contains some of the oldest untouched ice in the world: dating from the Eemian era, it is more than 131,000 years old. With an ice core from the Greenland ice sheet, David will have a once-in-a-lifetime opportunity to study more than 100,000 years of climate history.

Prior to the current interglacial period, which has lasted about 10,000 years, the last interglacial period was during the Eemian era. From previous studies, scientists have deduced that the climate, while similar to today’s, was also warmer by approximately three or four degrees. With current concerns over climate change and global warming, the opportunity to study the conditions of the Eemian era is too inviting to pass up. The information entombed in the Greenland ice sheet could explain the climate cycle, giving us valuable clues about our changing world.

“The Eemian could be our future,” explains David. “So we want to study it.”

This cooperative effort will combine the Danish scientists’ expertise in deep-core drilling with NRCan’s expertise in glaciology. The Danish scientists will drill down to a depth of 2.5 kilometres to obtain one of the longest ice cores in the history of scientific research. The ice core will be divided among the many scientists and studied in detail to illuminate the climate history of the Eemian.

NRCan scientists James Zheng will contribute by measuring trace-metal levels and Jocelyne Bourgeois by measuring the pollen in the ice. If Greenland was largely ice-free during the Eemian, then both the metals and the pollen levels would be very different. The combined efforts of NRCan’s glaciologists will address the question, “Did the Greenland ice sheet melt away during the Eemian?” The answers they discover will provide us with some insight into the future.

David Fisher’s project is one of many IPY projects that NRCan is undertaking. Keep an eye on Natural Elements to find out what other exciting projects NRCan scientists will be working on.