June 17, 2016

Different types of snow

Afternoon tee at new sofas.

The soft snow falling on the surface of the ice sheet undergoes a fascinating transition until it is buried deep in the ice sheet as solid ice with air bubbles. The intermediate material, the firn, is the material we work with in the trenches. In the drill trench the inclined trench has reached a depth of 4.2 m depth below the floor at which depth the firn is so hard it needs to be cut with a chain saw. The floor of the drill trench is hardened by using a mixture of soft fine grained surface snow and crushed snow blocks from the trenches. Hans-Christian is currently test a new laser instrument that measures the crystal surface area of a snow or firn sample. The snow crystal development in the upper firn is very dynamic and the surface snow crystal structure influences for example the reflectivity of the ice sheet surface - an important climate parameter. The ice blocks cut out from the inclined trench are excellent building blocks. Currently an artistic ice-block ice bar is developing in front of main dome. Hopefully weather will allows us to try it over the weekend.

What we have done today:

1. Removed 6 tons of snow blocks from the inclined trench in the drill trench. Depth 4.2 m
2. Testing new melt head configuration at Swiss drill test site. Casing currently pressurized at 6.7 bar
3. First analysis of snow crystal surface area using new laser instrument
4. Moved ice core buffer shelves into science trench and levelled buffer floor
5. Re-sampled snow surface profile in the clean snow area
6. Made food order and sorted cooks freezer

Weather today: Sunny but with high thin scattered clouds most of the day. Temp. -18°C in the morning increasing to -10°C in the afternoon. Wind 0-10 kt starting out NW and turning to SW.

FL, Anders Svensson

Excavations in the EGRIP catacombs.

Sarah and Niccolo in kitchen preparing Gnocci.