The Expedition PS151 of the Research Vessel POLARSTERN to the Atlantic Ocean in 2025

The expedition started on 13 November 2025 in Bremerhaven and ended on 12 December 2025 in Walvis Bay.The mission was characterised by the training of young scientists with participants from 24 nations.An international group of 25 young scientists were trained in the knowledge and techniques of oceanography during this training programme.The programme focused on sampling methods, sample processing and the handling of collected data.Further tasks during the transit cruise included chemical and physical measurements of gas, energy and mass exchange between the ocean and atmosphere.Observation methods and en route measurements played an important role.The trainees also received an introduction to the physics of the climate system, international climate negotiations and the goals of the UN Ocean Decade.On the so-called North-South Atlantic Training Transect (NoSoAT), they gained insights into marine science and carried out short experiments on the interactions between the ocean, atmosphere and climate as well as comparisons between observations and climate model simulations.The critical examination of science was highlighted in philosophical discussions.The trainees learnt about practical knowledge transfer and science communication through cooperation with educational institutions and social media contributions, among other things.Students based in different schools and universities were introduced to the mission of PS151 as well as work and life on board Polarstern via video link.The impressions of the voyage and awareness of the sea and climate change were thus brought directly into the classroom.The training programme was a joint project between the Alfred Wegener Institute, Trinity College Dublin (TCD), Partnership for Observation of the Global Oceans (POGO), SeaNetwork, the University of Galway, Shahjalal University of Science and Technology and the Irish Meteorological Service (Met Eíreann).The training programme was funded by the Nippon Foundation and POGO.NoSoAT OceanCapX is listed as an UN Ocean Decade activity.Polarstern arrived in Walvis Bay on 12 December 2025, marking the end of the expedition.