Drilling Failure


The drill whirred as it dug deep into a glacier. It cut 50 meters, then 60 meters down into the ice. As the drill dug, ice slid up inside its hollow center, forming a long cylinder called an ice core. Aſter each meter, Erin Pettit and a


team of scientists stopped the drill and pulled it out of the glacier. Ten they pushed out the ice core. Tey planned to take the cores to a lab to study them. Te cores contain information about


past climate. Dust, air, and snow fall on the glacier, where they freeze. What’s in the dust, air, and snow changes as Earth’s climate changes. Te deeper they drilled, the older the ice and climate. Te team wanted to drill all the way through


the glacier, about 300 meters. But the drill stopped whirling smoothly at about 80 meters. Heat from drilling melted some ice. Te water then refroze faster than the team could drill, keeping them from getting much deeper. Te team didn’t know what to do. Tey had


drilled into other glaciers, but water had never refrozen so quickly before. Tey even tried using antifreeze, but that didn’t work. Finally, aſter struggling for weeks and only drilling halfway through the glacier, the team gave up. Tey’d failed to reach the bottom of the glacier. Later, Pettit thought about the drilling on


that glacier. She compared it to other glaciers. Some glaciers are high on mountains and have cold, hard ice. Others are in valleys, where the ice is not as cold and melts more easily. Ten one day, Pettit had a new idea. Te


glacier where the drilling failed was an odd mix of very cold and slightly warmer ice. As the drill cut through a warm layer, the ice melted easily. Ten, when the melted water hit a cold layer, it refroze, making it hard to continue drilling. Pettit hasn’t figured out how to drill to the


bottom of the glacier yet. But “it was far from a failure,” the National Geographic explorer says. “It made me look at glaciers in a new way.”


14 NATIONAL GEOGRAPHIC EXTREME EXPLORER


Erin Pettit skis across a glacier. She planned to drill for ice cores to study ancient climate.


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