Justyna Czekirda

• Czekirda, Justyna; Rempel, Alan W.; Etzelmüller, Bernd & Westermann, Sebastian (2024). Spatiotemporal variations in frost cracking measures in two dimensions: A case study for rock walls in Jotunheimen, southern Norway. Geomorphology. ISSN 0169-555X. 453. doi: 10.1016/j.geomorph.2024.109112.
• Etzelmüller, Bernd; Isaksen, Ketil; Czekirda, Justyna; Westermann, Sebastian; Hilbich, Christin & Hauck, Christian (2023). Rapid warming and degradation of mountain permafrost in Norway and Iceland. The Cryosphere. ISSN 1994-0416. 17(12), s. 5477–5497. doi: 10.5194/tc-17-5477-2023. Fulltekst i vitenarkiv
• Czekirda, Justyna; Etzelmüller, Bernd; Westermann, Sebastian; Isaksen, Ketil & Magnin, Florence (2023). Post-Little Ice Age rock wall permafrost evolution in Norway. The Cryosphere. ISSN 1994-0416. 17(7), s. 2725–2754. doi: 10.5194/tc-17-2725-2023. Fulltekst i vitenarkiv
• Etzelmüller, Bernd; Czekirda, Justyna; Magnin, Florence; Duvillard, Pierre-Allain; Ravanel, Ludovic & Malet, Emanuelle [Vis alle 20 forfattere av denne artikkelen] (2022). Permafrost in monitored unstable rock slopes in Norway-New insights from temperature and surface velocity measurements, geophysical surveying, and ground temperature modelling. Earth Surface Dynamics. ISSN 2196-6311. 10(1), s. 97–129. doi: 10.5194/esurf-10-97-2022. Fulltekst i vitenarkiv Vis sammendrag

  The warming and subsequent degradation of mountain permafrost within alpine areas represent an important process influencing the stability of steep slopes and rock faces. The unstable and monitored slopes of Mannen (Møre and Romsdal county, southern Norway) and Gámanjunni-3 (Troms and Finnmark county, northern Norway) were classified as high-risk sites by the Norwegian Geological Survey (NGU). Failure initiation has been suggested to be linked to permafrost degradation, but the detailed permafrost distribution at the sites is unknown. Rock wall (RW) temperature loggers at both sites have measured the thermal regime since 2015, showing mean rock surface temperatures between 2.5 and −1.6 ∘C depending on site and topographic aspect. Between 2016 and 2019 we conducted 2D and 3D electrical resistivity tomography (ERT) surveys on the plateau and directly within the rock wall back scarp of the unstable slopes at both sites. In combination with geophysical laboratory analysis of rock wall samples from both sites, the ERT soundings indicate widespread permafrost areas, especially at Gámanjunni-3. Finally, we conducted 2D thermal modelling to evaluate the potential thermal regime, along with an analysis of available displacement rate measurements based on Global Navigation Satellite System (GNSS) and ground- and satellite-based interferometric synthetic aperture radar (InSAR) methods. Surface air and ground temperatures have increased significantly since ca. 1900 by 1 and 1.5 ∘C, and the highest temperatures have been measured and modelled since 2000 at both study sites. We observed a seasonality of displacement, with increasing velocities during late winter and early spring and the highest velocities in June, probably related to water pressure variations during snowmelt. The displacement rates of Gámanjunni-3 rockslide co-vary with subsurface resistivity and modelled ground temperature. Increased displacement rates seem to be associated with sub-zero ground temperatures and higher ground resistivity. This might be related to the presence of ground ice in fractures and pores close to the melting point, facilitating increased deformation. The study demonstrates and discusses the possible influence of permafrost, at least locally, on the dynamics of large rock slope instabilities

• Kristensen, Lene; Czekirda, Justyna; Penna, Ivanna; Etzelmüller, Bernd; Nicolet, Pierrick & Pullarello, Jose Santiago [Vis alle 10 forfattere av denne artikkelen] (2021). Movements, failure and climatic control of the Veslemannen rockslide, Western Norway. Landslides. Journal of the International Consortium on Landslides. ISSN 1612-510X. 18, s. 1963–1980. doi: 10.1007/s10346-020-01609-x.
• Hilger, Paula; Hermanns, Reginald; Czekirda, Justyna; Sæterdal, Kristin Myhra; Gosse, John C. & Etzelmüller, Bernd (2020). Permafrost as a first order control on long-term rock-slope deformation in (Sub-)Arctic Norway. Quaternary Science Reviews. ISSN 0277-3791. 251. doi: 10.1016/j.quascirev.2020.106718. Fulltekst i vitenarkiv
• Etzelmüller, Bernd; Patton, Henry; Schomacker, Anders; Czekirda, Justyna; Girod, Luc Maurice Ramuntcho & Hubbard, Alun Lloyd [Vis alle 8 forfattere av denne artikkelen] (2020). Icelandic permafrost dynamics since the Last Glacial Maximum – model results and geomorphological implications. Quaternary Science Reviews. ISSN 0277-3791. 233:106236. doi: 10.1016/j.quascirev.2020.106236. Fulltekst i vitenarkiv Vis sammendrag

  Iceland’s periglacial realm is one of the most dynamic on the planet, with active geomorphologicalprocesses and high weathering rates of young bedrock resulting in high sediment yields and ongoingmass movement. Permafrost is discontinuous in Iceland’s highlands and mountains over c. 800 m a.s.l,and sporadic in palsa mires in the central highlands. During the late Pleistocene and Holocene, Iceland’speriglacial environment varied considerably in time and space, dominated by glacialfluctuations andperiglacial processes. To evaluate the dynamics of permafrost in Iceland since the last deglaciation, weuse the output of a coupled climate/ice sheet model to force a transient permafrost model (CryoGRID 2)from the Last Glacial Maximum (LGM) through to the present. Wefind that permafrost was widespreadacross the deglaciated areas of western, northern and eastern Iceland after the LGM, and that up to 20% ofIceland’s terrestrial area was underlain by permafrost throughout the late Pleistocene. This influencedgeomorphological processes and landform generation: the early collapse of the marine-based ice sheettogether with the aggradation of permafrost in these zones initiated the formation of abundant and nowrelict rock glaciers across coastal margins. Permafrost degraded rapidly after the Younger Dryas, with amarked impact on slope stability. Permafrost that formed during the Little Ice Age is again thawingrapidly, and an escalation in slope failure and mass-movement might be currently underway. Our studydemonstrates that large regions of Iceland have been underlain by permafrost for millennia, facilitatinglandform development and influencing the stability of steep slopes

• Czekirda, Justyna; Westermann, Sebastian; Etzelmüller, Bernd & Jóhannesson, Tómas (2019). Transient Modelling of Permafrost Distribution in Iceland. Frontiers in Earth Science. ISSN 2296-6463. 7(130). doi: 10.3389/feart.2019.00130. Fulltekst i vitenarkiv

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• Snook, Paula; Hermanns, Reginald Leonhard Manfred; Czekirda, Justyna; Sæterdal, Kristin Myhra; Gosse, John C. & Etzelmüller, Bernd (2023). Permafrost controls long-term displacement activity of large unstable rock slopes in subarctic Norway.
• Hilger, Paula; Hermanns, Reginald; Czekirda, Justyna; Sæterdal, Kristin Myhra; Gosse, John C. & Etzelmüller, Bernd (2020). Is permafrost a first order control on rock-slope deformation in Norway?
• Etzelmüller, Bernd; Patton, Henry; Schomacker, Anders; Hubbard, Alun Lloyd; Czekirda, Justyna & Westermann, Sebastian (2019). Permafrost dynamics in Iceland between 18 ka BP and today – model results and geomorphological implications. Vis sammendrag

  Periglacial processes and the dynamics of permafrost is a decisive factor for slope stability locally, and for understanding landscape development over longer time scales. Iceland has a highly dynamic landscape because of young bedrock and associated high geomorphological process rates, leading to large material production and frequent gravitational processes in the present periglacial realm. At present, permafrost in Iceland is widespread in mountain settings over c. 800 m a.s.l. and sporadically in palsa mires in the central Highlands. However, during the late Pleistocene and Holocene, the periglacial environment in Iceland must have varied strongly in time and space, with subsequent imprint in the landscape. To evaluate the dynamics of permafrost in Iceland since the onset of the last deglaciation, we used the forcing and output of a 3D, time-integrated ice sheet model to run a transient permafrost model (CryoGRID 2) between the onset of the last deglaciation (c. 18 ka BP) until today. The permafrost model was forced by either modeled sub-glacial temperatures if ice-covered, or air temperatures if the area was deglaciated. The results give insights into the possible age of permafrost in Iceland, distinguish areas with wide-spread paleo-permafrost and let us determine the persistence of permafrost in the different areas. The presentation discusses these results in the light of periglacial processes, landforms and landscape development

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