Cryo-conditioned rocky coast systems: A case study from Wilczekodden, Svalbard

Abstract

This paper presents the results of an investigation into the processes controlling development of a cryo-conditioned rock coast system in Hornsund, Svalbard. A suite of nested geomorphological and geophysical methods have been applied to characterise the functioning of rock cliffs and shore platforms influenced by lithological control and geomorphic processes driven by polar coast environments. Electrical resistivity tomography (ERT) surveys have been used to investigate permafrost control on rock coast dynamics and reveal the strong interaction with marine processes in High Arctic coastal settings. Schmidt hammer rock tests, demonstrated strong spatial control on the degree of rock weathering (rock strength) along High Arctic rock coasts. Elevation controlled geomorphic zones are identified and linked to distinct processes and mechanisms, transitioning from peak hardness values at the ice foot through the wave and storm dominated scour zones to the lowest values on the cliff tops, where the effects of periglacial weathering dominate. Observations of rock surface change using a traversing micro-erosion meter (TMEM) indicate that significant changes in erosion rates occur at the junction between the shore platform and the cliff toe, where rock erosion is facilitated by frequent wetting and drying and operation of nivation and sea ice processes (formation and melting of snow patches and icefoot complexes). The results are synthesised to propose a new conceptual model of High Arctic rock coast systems, with the aim of contributing towards a unifying concept of cold region landscape evolution and providing direction for future research regarding the state of polar rock coasts.

High Arctic coasts at risk—the case study of coastal zone development and degradation associated with climate changes and multidirectional human impacts in Longyearbyen (Adventfjorden, Svalbard)

“…In general, over the last decade, Svalbard coastal studies have been concentrated on the coastal zone response to shifts in sediment supply associated with changes in local ice masses and paraglaciation (e.g., Bourriquen et al, ; Mercier & Laffly, ; Sessford, Strzelecki, & Hormes, ; Strzelecki et al, ; Zagórski, ); ephemeric pulses of sediments from snow‐fed streams (Lønne & Nemec, ; Strzelecki, Long, & Lloyd, ); or the controls of coastal permafrost development (Kasprzak et al, ). Recent years had also brought some advances in local rocky coast systems that dominate over coastal landscape in numerous Svalbard fjords (e.g., Kasprzak et al, ; Strzelecki, ; Strzelecki, ; Strzelecki et al, ; Świrad, Migoń, & Strzelecki, ). Most recently, Jaskólski, Pawłowski, and Strzelecki () reported on the impact of geohazards including coastal changes on the state of abandoned Arctic town—Pyramiden in Northern Billefjorden.…”

Evolution of Near-Shore Outwash Fans and Permafrost Spreading Under Their Surface: A Case Study from Svalbard

“…In the case of the Svalbard shore, the influence of the saline and relatively warm sea water on the permafrost in the land zone has not been, until recently, given adequate attention, and the existing schemes of groundwater circulation have not concentrated on the coastal zone [98,99]. The phenomenon of sea water intrusion inland has been illustrated in the Hornsund region with the use of electrical resistivity tomography [6,7].…”

“…Recent thermal measurements of the near-surface ground parts performed in the vicinity of the study area indicate that in the summer, the tundra-covered land surface may reach temperatures above 20 • C [77], and the temperature of the ground at the depth of 1.5 m may reach up to 4.3 • C in August [27]. Based on geophysical imaging, a conclusion may also be drawn that the permafrost base in the coastal zone is additionally influenced by the thermal currents and salination of the seawater [6,7].…”

“…Based on the available information, a conclusion may be drawn that despite the warming climate, permafrost still aggradates in the ground exposed due to the retreating of the glaciers [3][4][5]. However, the evolution of permafrost seems more complicated in the case of fluvio-glacial sediments in the direct vicinity of the sea, where the land is thermally and chemically affected by the sea water [6][7][8]. It can be assumed that the sediments filling the Svalbard bays and fjords in recent decades are subject to permanent freezing; however, this process is limited from the seaside by the thermal and chemical impact of sea water.…”

The Quaternary rivers of the Jurassic Coast region: From the Neogene to the Anthropocene

“…7). Indeed studies in the High Arctic have shown how periglacial processes and especially the interaction of permafrost, variable lithology, weathering and slope processes controls cliff evolution with wave action rejuvenating the system during high sea level stands producing high rates of cliff retreat (Strzelecki et al, 2017). Ostracods suggest the presence of brackish pools, so it is likely that these loams were deposited adjacent to a high sea level and, stratigraphically, should date to the last cold stage (Devensian).…”