May 29, 2024

A lull in the wind

Left: Dorthe getting the logger mounted in the calibration rig, with assistance from Martin and David below. Right: Drone panorama of Martin (at the sledge), David (resting in the dug out) and Susanne (resting on the surface) right after the excavation of an ApRES station away from camp.

EGRIP camp is situated somewhat to NE of the highest point of the Greenland ice sheet, so our most common wind direction is down the ice sheet, i.e. from SW, a typical katabatic wind pattern. This predominant wind pattern, driven by the topography of the ice sheet, also means that we rarely have calm conditions here at EGRIP. After a windy start to the day, the wind did, however, decrease during the afternoon, and we had no wind at all in the evening. Hence, this was a good opportunity to carry out tasks where a lull in the wind is needed. Calibrating the bore hole logger is one such task, as it needs to be suspended, so it hangs in a nice and vertical fashion. Wind will tend to push the logger a bit away from a completely plum position, so calm conditions are essential. Thus, Dorthe used the nice lull in the wind this evening for a calibration.
Work on the surface is also much easier if winds are low, so both grooming and retrieval of two more ApRES stations were done today.
In the drill trench, the Cryo-pølse was deployed twice, but unfortunately signal was lost before reaching the bed, at both occasions, so the Cryo-pølse had to be resurfaced for inspection/evaluation of the cause. In between the first and second deployment, the drillers took the opportunity to filter the bore hole two times.
In the evening we had another relaxing movie night, enjoying the candy, couches and comfy chairs upstairs in the dome.

What we did today:

1. Deployment of Cryo-pølse in deep bore hole twice, signal lost at 900m/1600m depths.
2. Two filter runs to further clean up remaining chips in upper part of bore hole.
3. Continued preparations for our intermediate depth drill system in white garage.
4. Groomed apron for Skier, Basler and Twin Otter operations.
5. Preparation of tanks for defueling and fueling operations.
6. Retrieved two more ApRES station, for a total of 7 recovered stations.
7. Logger calibration carried out using the rig.
8. Movie night.

Weather today: Mostly sunny and temp. from -19°C to -11°C. Wind: decreasing from 20 kt before lunch to completely calm conditions in the evening and night, while turning from SSE to SW. Visibility: Unrestricted, except for some snow drift before lunch.