29 September 2025
Written by Helge Niemann
The first days of our expedition have passed in a blur aboard the RV Pelagia. For the next two weeks, she is our home while we work in the North Sea. We are not the first science crew - far from it. For more than 30 years Pelagia has been the flagship of the Dutch research fleet, carrying countless scientists and being central to many discoveries and breakthroughs.
But this is her final voyage.
We started with a few technical headaches. Winches, hydraulics, instruments meant to measure autonomously at the seafloor - things did not always go as planned. They never do. An expedition is never just science out of the box, it is also improvisation at sea, in conditions where gear will eventually fail. The ship’s crew and our engineers pulled together, solved the problems, and got us moving again. That is how expeditions work: nothing runs perfectly, and progress depends on teamwork - more than on technology.
Our mission? Energy. Methane, to be precise. Large amounts of methane are buried in deep sediment layers of the North Sea and thousands of platforms exploit this gas. But nothing lasts forever: Once a reservoir is no longer viable, the boreholes are sealed. Yet recent findings suggest some of these old wells leak. This raises concerns, as methane is a potent greenhouse gas. At these abandoned wells, we measure whether they leak, how much methane escapes to the water column, and how much is consumed by microbes before it reaches the atmosphere.
For the coming two weeks, Pelagia will do what she always did best: bring scientists to sea, despite problems, despite weather, and make science happen. She has been my working home on seven expeditions across the Atlantic Ocean. I know her working deck, her labs, her bridge… The ship carries many of my scientific memories and leaving Pelagia behind feels a bit like losing a home.
For me, it is an honour to guide this last expedition of Pelagia as cruise leader. But every ending carries the seed of a beginning. Pelagia’s successor, the RV Anna Weber-van Bosse, is in the final stages of construction and will enter service next spring. I will leave Pelagia with one eye crying and the other laughing: farewell to a ship that carried us well, and forward to a new home at sea.
Helge Niemann
