Monitoring terrestrial high-arctic ecosystems is important because of their great exposure to global warming. Ideally, these ecosystems are monitored continuously to capture the evolution of their characteristics year-round. This requires a pervasive monitoring infrastructure that collects data automatically. A consequence is that measurements that have traditionally been obtained manually should now be obtained with automatic measurement systems. Deploying such systems in a high-arctic environment raises specific challenges due to limited access, extreme weather and the absence of communication infrastructure. In the MANA project, we tackle these challenges in the context of a sensor network based data acquisition system for year-round lake monitoring in North-East Greenland. In this paper, we describe our system design and report the lessons we learnt from the first year of deployment. We emphasize the issues we underestimated initially: i.e., the consequences of operating in a remote region, the impact of extreme weather not only on system design but also on operator activities, and the demands that derive from the absence of communication infrastructure. We also reflect on the supremacy of Murphy’s law for unattended systems operating in hostile environments and on what it means for system design.