Ice coring is an important activity for scientists in the polar regions. Like many things in nature, ice tells a story about the climate and a changing ecosystem. The Northwest Passage Project is using ice cores for a couple different research projects.
I was lucky to be included in a small group of scientists that flew to an ice floe in one of the onboard helicopters. Landing on an ice flow is relatively easy since only about 30cm of stable ice is necessary to support the weight of the helicopter. The total weight of the aircraft, approximately 1 ton, is spread out over the large skids. When the pilot lands the helicopter, he thrusts it down into the ice a number of times in order to test if it is stable or see if cracks form. Safety is always of the utmost importance when on an ice floe. It is required that everyone on ice be wearing a float suit, lifejacket and ice picks.
Science work begins by assembling the ice coring bit. The ice corer is a large tube with small blades on the end that can cut and trap the ice in the tube. We are able to cut 1 meter sections of the ice one at a time. As we go down in depth, we need to add extensions to the corer in order to get to the appropriate depth. This apparatus is attached to a high power electric drill to make operations easier. Once we have reached the bottom, all the ice sections are laid out and cut into 10 cm pieces. We measure the temperature of each piece before bagging them and placing into the cooler.
The ice where we sampled was categorized as multiyear ice. This means that it has been around for multiple years and did not melt in the previous summer. The ice we drilled was about 2.4 meters thick. Temperature of the ice in the bottom layers was warmer than should be expected so we can tell that the bottom layers of this ice will melt this summer.
Once back onboard the Oden, an ice core is immediately taken to each of the scientists who requested one so that they can begin to analyze and process their samples. On this particular trip, we returned with three ice cores: one for the microbiology group, one for methane analysis, and one for oxygen isotope analysis.