July 18, 2019

Working with the Lisa Box

Fixing the Lisa Box

Zurine and Iben are working on the Lisa Box. The idea is that a firn core can be placed on the melt head on top of the box. In the box the conductivity, calcium and peroxid are measured on the meltwater stream. The problem is that water is leaking into the box and destroying the measurements but progress is made in stopping the melt and repairing the instruments.

What we did during the day:

1. CFA measurements of 39 bags, last bag 3595.
2. PP measurements, Volume samples
3. Station for atmospheric moisture sampling and isotopic measurement is active.
4. Test runs with the Mills Cross Radar on the skiway
5. Continued work on rover
6. Moved drums to surface
7. Cleaned the top shelf of the Carpenters Garage
8. First fishing attempt to recover CryoEgg at the bottom of the EGRIP deep borehole

Ad 1: Will, Abby, Cloe, Sofia and Florian have processed 39 bags and this is the record of this season. Congratulations.

Ad 8: The 12 cm diameter CryoEgg was lost in the 13 cm diameter borehole last weekend. Since then Romain has been working on a tool to recover the Cryoegg. The tool is a cylinder with 6 core catchers and the trick is to get the egg into the cylinder so the core catchers can grab the egg. The difficult part is the very small clearance between the diameter of the egg and the diameter of the borehole. The cylinder walls must be thin so the free room for the core catchers is very small. Also, the size of the egg grabber is so close to the borehole diameter that both descent and ascent are VERY slow. While Trevor and Romain probably did grab the CryoEgg it got lost again. The grabber will be improved with stronger springs on the core catchers and bigger holes to allow the liquid to flow around the egg in the grabber.

EGRIP population is 23

Weather: Wind from 6kts to 12 kts from NW turning to W Mostly overcast. Temperatures from -13°C to -5°C.

FL, Dorthe Dahl-jensen

The first version of the egg grabber with a 3D printed CryoEgg attrap.