by Alexandre Anesio
The previous blog by Liane G. Benning clearly described the journey of trying to put together a massive and ambitious fieldwork programme for the Deep Purple project, going from the microscopic scale to remote sensing information to demonstrate the impact of ice algae and other impurities on the darkening of the ice, their controls and dynamics. A bunch of names from the brave team will be mentioned here and you can learn more about the team members on our “team” page.
No doubts, we started in a very high mood. However, as team 1 (Principal Investigator Martyn Tranter, Lasse, Rey, Joe, Ian, Eva, Shunan, and Lou) started their journey from Denmark on the 1st of July and began the process of setting up the camp, they were hit by a number of obstacles. The weather was far worse than predicted, delaying helicopter trips to the ice camp from the lovely Greenlandic town of Qaqortoq (https://visitgreenland.com/da/destinationer/qaqortoq/). Corona just started to hit Greenland, which had faired very well until ca one week after we arrived. We had to separate our teams between vaccinated and non-vaccinated members of the group, reschedule the science programme and wait for good weather. The task of setting up a camp for ca 16 people at a time on the ice was more challenging than anticipated. Team 2 (myself, Marie, Ate, Frederik, Chris, Pamela and Leeds University beloved collaborator Jim McQuaid) arrived on the 8th of July with half of team 1 still in Qaqortoq. It took five days before we were all on the ice, but we had to leave Martyn Tranter behind in Qaqortoq to serve as a very needed organizer and local fixer on the ground, securing communications between ice and civilization, sending of the samples back to Denmark/Germany, organising flights and all sorts of things (even buying 15 rain ponchos that turned out to be a quite nice addition to keep the team on the ice dry).
Deep Purple camp when it was at its max capacity. Photo Alex Anesio
Team 3 (Principal Investigator Liane G. Benning, Helen, Elisa, and Laura Perini) arrived on the 12th of July to Qaqortoq but only managed to get on the ice ca 5 days later since Qaqortoq went into lockdown. Meanwhile, Teams 1 and 2 had just experienced 52 mm of rain on the ice in a 24 h period. Within just one 1 h of Team 3’s arrival, another 47 mm of rain fell. Considering the conditions (both weather and corona uncertainty), Team 4 had to cancel their travel plans, but their science plans were re-distributed between us to ensure all science was carried out. This left us behind time-wise, but then a spell of good weather hit, and that, coupled with great spirits in the team and the desire to get a lot of work done, was just what we needed.
A massive transformation on the ice was now happening in front of our eyes with the ice algae blooming. The rain had seemed to wash microbial cells together with impurities, but a few days of dry weather in the middle of the summer darkened the ice at incredible speed. At this point, the camp was running like a watch; carnivores were eating like vegetarians, freezer, fridge and -80 degree freezer were getting full with samples, the solar panels were providing all the energy necessary to fuel all sorts of equipment, and our journalist and TV visitors managed to make it all the way to the ice sheet (no names mentioned yet ;-)). All this happened as we received news from the civilization that Greenland was having unprecedented amounts of rain and the IPCC report was released, demonstrating the urgency of more understanding of feedback mechanisms between different stressors and fueling the young scientists in the project with a clear sense of purpose.
First lot of -80 degree samples for omics and pigments arriving with teams 1 and 2.
Slowly, parts of Teams 1, 2 and 3 left this year’s field camp, having done their jobs brilliantly. On the 6th of August, I arguably had the most glorious day of my scientific life. The final team of six scientists (Lou, Shunan, Liane, Elisa, Laura P, and myself) and our field logistics whizz Lasse woke up to blue skies. As luck would have it, that day satellites were passing above our location and we had a full day collecting data from the microscopic scale to cm and then meters to make the full connection of what we see on the ground and what satellites observe from the sky. The ice algae were in full bloom and the ice surface was full of very active ice algae. We walked about 20,000 steps, collecting pictures of the ice, spectral signatures and samples for all sorts of omics. Flights with the drone matching the satellite passing were also done. It was a tiring day that went on throughout the night, with additional midnight sampling to check how the ice algae behave when it is dark. Our luck continued during the few hours of darkness, as a rare event of northern lights put icing on the cake ̶ what a fantastic day.
Left: Ice surface (tens of cm scale). Picture taken from 1.7 m distance from the ice. Photo Alex Anesio
Right: Ice surface picture taken with a handheld microscope (mm scale). The pigmented ice algae is very abundant on the ice (example of a filamentous algae shown by the arrow), which essentially explains a lot of the darkening of the ice. As the ice becomes darker, more melting occurs. Photo Alex Anesio
After that, it was time to start the long process of decamping. Not easy, but it went super-smooth. Almost 4 tonnes of science and camping gear had to be removed from the ice, dried back in Qaqortoq and carefully packed into a container for transport back to Aarhus University at Risø and the German Research Centre for Geosciences in Potsdam labs. Most importantly, the ambitious plan set at the beginning of the project paid off. We shipped back 100 kg of frozen (-20 degrees) samples, 150 kg of cold samples and 6 cryoshippers (-80 degrees) full of samples for metabolomics, metagenomics, transcriptomics, proteomics, pigments, viruses, etc. Lots of experiments were run on the ice to investigate how ice algae respond to various physico-chemical conditions and how they interact with the other members of the microbial community, and a range of bacteria, viruses and fungi are being cultured with novel approaches. Terabytes of spectral data (drone imagery and ground truth measurements on cm scale) are now available.
Day or night, dry and wet, Deep Purple never stopped for about 5 weeks on the ice. Photo Alex Anesio.
I could not have had a better field season. A very resilient group of young scientists went through rain and pain and did everything they had planned. Deep Purple transformed wet misery into opportunity. Climate change will likely bring more wetness to the ice sheet. Scientists in Deep Purple did not hesitate to keep collecting samples in the rain, and this might give us a peek preview of how microbial communities behave in the rain on the ice; how the weathering crust is changed in the rain; and how fast it recovers after just a few hours of sun. All these data are fundamentally important for the parametrization of ice albedo into future climate models.
I just want to finish to say a huge thanks to this amazing group of young scientists, wonderful friend and stimulating PIs and flexible supporting project managers, for their friendship on the ice, resilience, enthusiasm and hard work and for making me eat less meat, although I am not sure I will be able eat lentils again for at least 6 months.
