Ok, this was a longish field season.

We returned to the Isunnguata Sermia upwelling site (we test-sampled in 2025) to do the real thing: determine the origin and reactivity of organic matter in the Greenland Ice Sheet’s subglacial ecosystem as part of the new OReOS project. Under the in-field leadership of Arthur we spent 6 weeks collecting samples of subglacial runoff and suspended sediment for all sorts of biogeochemical analyses.

We had a great team, consisting of the core project team of Arthur, Marie, and Marek, our undergrad student Luko Počinek, our long-term collaborators and friends K1 and K2 (aka Jakub Žárský and Jakub Trubač), our former postdoc Philip Píka, now at ULB, Terka Vošická, a PhD student from the DICE group, and also, after a long 8 years (after the famous What-the-Flux project), Anne Kellerman, now at the University of Pennsylvania, joined for a week, bringing additional experience, expertise, and techniques.

As a bonus, we were joined for a few days by the great photographer Sean Gallup — and one of his pics made it as the image of the week in Nature Briefing Anthropocene! (Arthur’s in it, of course!)

In total, approximately 500(!) litres of water was filtered through an assortment of filters and some 1.5 kg of sediment collected; some of these sample have safely made it back already, while some are still in transport. Analyses and lab experiments will follow in the coming months.

Overall, this has been an exciting and successful (and also, as some say, rather painful) season and we are looking forward to seeing some results soon(ish)!