After a number of other odd jobs throughout the day, I was on the phone with Ken in Fairbanks trying to troubleshoot our internet problems when Terry shouted that we had hit the bottom. Apparently the thermal drill hadn’t moved in quite some time, indicating that it was no longer hitting ice. We pulled the drill out and lowered the camera down and, sure enough, 151.3 meters down the hole was rock! It is of course unclear whether this was a random rock or the actual bed of the glacier, but this was the depth I initially anticipated based on our radar measurements in the area, and in any case we had no means to drill further, so we called it good. After pulling out the camera, we installed the thermistor string into the hole. This process took about an hour, 55 minutes of which was spent untangling 160 meters of thermistor string cable.
Matt: “Is there a rat to go with this nest?”
The obligatory hero shot.
The real heroes.
Down she goes. When she comes up, nobody knows…
These thermistors are 10 meters apart and record temperature. Once the hole freezes back over (if it does) we will then have some record of ice temperature versus depth, and hopefully these measurements will continue over many years. A somewhat counter-intuitive process we anticipate is that as climate warms, the ice in this region will actually get colder. The reason is that this region is now an accumulation area, but if climate continues to warm it will change to an ablation area and the firn which now keeps the deep ice warm through refreezing of surface meltwater will disappear. This process is likely already occurring in the lower cirque, where we plan to drill our third hole.