High productivity in camp

The firn gas crew (Johannes, Emily and Todd) getting ready to launch the bladder. The photo is taken from Todd’s drone.

In the wet drilling operation, we had problems with packing of chips in the morning, resulting in relatively short cores. We decided to change to so-called step cutters, where each cutter only cuts 1/3 of the width of a normal cutter.

We have better success picking up all the chips when we use the step cutters, and the change brought us back to cores with an average length of about 2 meters per run.

We stopped earlier to allow time for showers and Saturday night dinner preparations, but still produced 17.74 meters of core in 10 runs.

We are very satisfied with the current mode of drilling, which is both fast and produces ice cores of high quality. Logged depth 222.38 m.

After more than two weeks of steady work, the firn gas sampling program draws to an end. Johannes Freitag led the program by drilling two shallow holes to about 73 m in increments interrupted by bladder launches to the bottom of the drilled portion.

The inflated bladder isolates the deep firn air from the surface allowing us to pump air from the firn through 120m long tubes all the way to our pump box where individual flasks are filled.

Upon the return to their lab, Emily Doyle and Todd Sowers will measure the composition of the firn air in some of the flasks in conjunction with numerous collaborating labs to insure a full suite of data are available to develop a computer model of air transport within Renland firn.

The model and data will help us to understand the nature of gas transport and the gas age distribution in the bubble close-off region.

Over the past two weeks we have drilled, logged and measured density on 145 m of ice core and filled 121 flasks.

Weather: We have had scattered clouds with patches of blue sky, northerly winds around 3 m/s, and temperatures ranging from -14°C to only about -5°C. The nights (what most other people would call the days …) are getting so warm that several people in camp are having trouble sleeping when the sun is shining on the tents.


Best,
Sune O. Rasmussen, RECAP FL