The polar regions and the oceans, as key players in the global climate system, are in flux. A large international and interdisciplinary consortium is observing and investigating this phenomenon to improve our prediction of short-term fluctuations and long-term trends for our future. In this keynote speech, we present the challenges that we had to take into account when organising the one-year expedition into the Arctic. We shares insights into this unique expedition and show first research findings, which help to inform us about the effects of climate change.