100,000-year outdoor celebration in summerly conditions with EGRIP camp participants plus three Twin-Otter crew and four Greendrill scientists.

Drilling continues surprisingly smooth with another four long ice cores drilled today. The ice appears still to be in stratigraphic order and matching it up to NGRIP shows that we almost certainly have passed the age of 100,000 years. The 100 ka ice was drilled yesterday and measured today. While 100,000 years certainly is a milestone, it is not a climatically interesting age as it is just sitting in the middle of the long mild period known as GI-23. The next interesting climatic transition is at the abrupt warming onset of GI-23 that occurs around 104,200 years. The Greenland warming at the GI-23 onset most likely occurred because the North Atlantic deep-water formation was (re-)initiated at that time (the ‘Gulf stream’ became active) resulting in melting of sea ice and strong warming of the entire North Atlantic region. The onset of GI-23 is also where the ‘Summit cores’ GRIP and GISP2 lost their stratigraphic continuity due to folding of the deep ice layers. Therefore, we are quite excited to see what happens to the ice here at EGRIP at that transition. In fact, the ice that is pulled out of the ice sheet now in the form of ice cores fell as snow not far from the Summit of Greenland at the time. Since then, it has been sinking into the ice sheet and flowing towards the coast to end up at EGRIP today.
The pullout from the Greendrill site is continuing. Today one shuttle brought back more equipment and the two last scientists to civilization (EGRIP). The afternoon weather at the Greendrill site did not allow for a last shuttle flight, so that is postponed for tomorrow. If everything goes smoothly, the Twin-Otter may go with the entire Greendrill team back to Kanger tomorrow afternoon.

Weather today: Fairly nice weather most of the day with overcast coming and leaving and high temperatures from -15°C to -10°C. A very calm evening making perfect conditions for an outdoor 100 ka celebration. Wind, 2-14 kt from WNW.

Is this a bird’s cage with central heating? No, although we are willing to go far for our feathered friends, the box is actually part of the setup for the acoustic sensor for the drill liquid sounder sensor.

Here the full setup with a loudspeaker connected to the drill hole lid via a tube. The sound from the loudspeaker is reflected by the drill liquid in the borehole and detected by a microphone.

100,000 years passed and bringing back Greendrill team