Today was dedicated to the cryoconites. I have the good luck that several colleagues have accompanied me, as the drilling is hard work for the cryoconites at Utsteinen. The ice lid is quite thick. I was with Olivier Francis (professor of geophysics from U of Luxembourg), Stefan Kneifel (meteorologist from the University of Köln) and Jacques Richon (our Swiss doctor and field guide).
On the picture above, Olivier and myself are measuring the size of the cryoconite at the foot of the Utsteinen nunatak. The diameter was 5 meter.
I guess that the picture above clearly shows that the drilling is very difficult, even if the drill has an engine.
Here, Stefan helps me with the oxygen titration. I have already measured the pH and oxygen two weeks ago. It was very interesting to find a high pH (9.6) and high oxygen concentration (12.5 mg/l). This could mean that there is a high photosynthetic activity inside the cryoconites. However, last year when we drilled into the cryoconites with Josef Elster, the oxygen concentration was lower. This could be linked maybe to the weather as it was cloudy at that time. And photosynthesis depends on the availability of sun, which could also influence the water temperature.
Olivier reminds me of the instructions to measure the oxygen concentration using the Winkler method. We have chosen this method because it does not depend on an apparatus with electric batteries. This can be very important at low temperatures, where the batteries are empty in a very short time.
In addition to the measurements at one particular time, we are installing temperature and humidity loggers to register continuously these parameters. Stefan has made a nice design, where the loggers are placed within plastic tubes, so that we can put them and take them out easily. You can see two tubes sticking out of the ice lids on the picture. We will see if this design is working well. I hope to be able to estimate the period of time where the cryoconite communities are active.
Below, Stefan and Jacques are drilling into a cryoconite.
Thanks for all photos to Stefan Kneifel and Olivier Francis.