Day 15: short update
In the firn air camp today we reached a level (about 66 m) where the flow of air got very low. The CO2 concentration indicates that the air is from the 1980s. We managed to fill all the low-volume samples, even we were not able to sample the same amount than at other levels. We then also tried to collect high pressure samples, although the conditions were not really adequate for the high volume compressor. It would have taken about 4 hours to collect the usual sample, but after about 1/3 of the time it looked like surface air had entered the collection system. So I stopped the sampling and the last sample is likely contaminated with surface air. So, it seems that we have reached the end of the firn sampling, at least for the big samples. We will make another attempt tomorrow to test whether there is a layer below from which we can still pump air.
I end this short blog for today with a photo of myself cutting an ice core. I had a lot of training by cutting trees at home this spring together with my neighbor Stijn, and the ice core was a piece of cake.