Complex geohazards at a high-priority Arctic cultural heritage site at Russekeila – Kapp Linné, Svalbard

• Full geohazard assessment of a high-priority Arctic cultural heritage site. • Russekeila West is half destroyed by rapid river- and coastal erosion. • Russekeila East is exposed to permafrost hazards, gullying, slumps, solifluction. • Over the last 66 years, the Linnéelva-river outlet shifted more than 90 m sideways. • Svalbard’s rapid environmental changes may speed up pre-existing geohazard processes. Geohazards are a global phenomenon, affecting both modern infrastructure and remnants from history. The extreme climate change occurring in Arctic Svalbard makes it one of the most environmentally sensitive areas for cultural heritage (CH) in the Northern Hemisphere. The physical landscapes, comprising mountain slopes, glacial, fluvial, and coastal processes, in conjunction with the permafrost setting, collectively constitute a complex set of conditions that present significant challenges to the conservation of CH. In this study, a combination of fieldwork and remote sensing methods is employed to map and gain an understanding of the geological, topographical, and geomorphological setting of a nationally high-priority Arctic CH site, Russekeila, situated at the mouth of the Linnéelva river on the west-central coast of Spitsbergen. It is demonstrated that a range of hazards, including fluvial, coastal and permafrost processes, both gradual and rapid, have the potential to impact this unique CH. The relative importance of the hazards is evaluated in terms of their present activity. The findings indicate that the rapid coastal migration of the river mouth directly erodes a bluff of marine sediment origin, leading to the destruction of CH. Furthermore, slow but continuous deformation by surface solifluction affects other parts of the CH site. The geomorphological mapping has also identified the presence of permafrost-dependent thaw slumps and thermo-erosion gullies near the CH. These processes are rapid when initiated, but the precise future initiation points are difficult to predict. The continued future warming of the permafrost and changes in hydro-climatic conditions may result in the activation and expansion of all these processes, thereby threatening an even greater proportion of the fragile CH at Russekeila. Integrated studies of this nature, which combine geomorphological mapping with the monitoring of processes and environmental conditions over time, represent a comprehensive approach to the assessment of potential hazards, thereby providing a solid foundation for the development of effective preservation strategies.