July 1, 2019

Volcanic ash layer

Left: Eliza looking through the core section containing a visible volcanic ash layer. Right: Close up of the ash layer.

Past volcanic eruptions can often be detected in Greenland ice cores using highly specialized measurement techniques, but it is a rare treat to be able to see ash downfall in a Greenland ice core with the naked eye. Hence the excitement was palpable in the science trench today, when a clearly visible ash layer emerged in one of the EGRIP ice cores sections processed today.
Otherwise work continued Monday with the drillers soldiering on keeping the winch spooling issues from deteriorating further while producing high quality ice cores to the great satisfaction of the loggers. Hard core breaks are, however, another concern of the drillers, somehow the ice here at EGRIP seems to be exceedingly tough to break. We all hope that pulling power of the winch, and the ingenuity of the drillers will continue to prevail in the coming days and weeks.
In the science trench the pace of the processing increased today, as the ice core is of high quality and the processing crew put in another great team effort. Also CFA and PP measurements are continuing at pace, with the PP crew processing the last brittle ice core samples today and moving on to the glacial ice processing again.
On the surface both atmospheric and surface measurements continue, and the Picarro meant for measuring drone samples has been put to good use by Kevin, Abby and Sonja in support of Abby’s surface science program.
Finally this years re-measurement program of the GPS stakes around EGRIP continued as well.

What we did during the day:

1. Drilling 6 runs despite winch spooling issues.
2. Logging 6 runs, logged length 14.65m, logged depth 2036.79m.
3. Ice core processing of 60 bags, last bag 3337.
4. CFA measurements of 32 bags, last bag 1880.
5. PP measurements ongoing in science trench, last bag 3236 (brittle ice finished).
6. Measuring GPS stakes around camp.
7. Station for atmospheric moisture sampling and isotopic measurement is active.
8. Grooming of Skiway.

EGRIP population is 33.

Weather: Wind between 8kts and 13kts turning form NW to NE. Mostly cloudy with outbreaks of snow. Temperatures from -12°C to -5°C.

FL, Bo Vinther

A new air intake on the atmospheric measurements size putting the “drone” Picarro to good use in the surface science program. Sonja and Abby finalizing the installation, while Alexandra monitors progress.