Trond Eiken

• Kuhn, Dirk; Hermanns, Reginald Leonhard Manfred; Fuchs, Michael; Schüßler, Nick; Torizin, Jewgenij & Aga, Juditha [Show all 9 contributors for this article] (2025). Warming-induced destabilization of polar coastal rock cliffs and the role of thermokarst: A case study of Forkastningsfjellet on Svalbard. Science of the Total Environment. ISSN 0048-9697. 968. doi: 10.1016/j.scitotenv.2025.178807. Full text in Research Archive Show summary

  Deep-seated landslides pose a potential threat to coastal settlements, shipping routes, and the natural environment of the polar regions. However, the occurrence, dynamics and impact of such landslides under a warming climate are poorly understood owing to scarce observational data. Here we investigate two deep-seated rockslides on the permafrost coastline of Forkastningsfjellet, Svalbard. Along this coastline, which was dormant for at least the last 80 years, a 175,000 m3 rockslide occurred in August 2016, followed by a second rockslide of 750,000 m3 in November 2022. Based on extensive field data collection starting in 2017, which includes the acquisition and differencing of drone-based DEMs, point-based displacement measurements (dGNSS), ground surface temperature logging, and field mapping, we document accelerating surface deformation and the redirection of the drainage pathways that drive the dynamics of the unstable slope. We show that the 2022 rock slope failure was governed by rapid fluvial incision and accelerated thermokarst development along colluvium-covered, pre-existing zones of weakness, which we interpret as permafrost degradation and enhanced surface run-off resulting from climate warming. We attribute the final triggering of the rockslide to the loss of cohesion and increasing pore water pressures due to thawing ground and cleft ice within the joint system. Looking to the future, we argue for the likely emergence of a positive feedback loop between increasing water availability, due to permafrost thaw and changing precipitation trends, and rock mass deformation.

• Aga, Juditha; Piermattei, Livia; Girod, Luc; Aalstad, Kristoffer; Eiken, Trond & Kääb, Andreas [Show all 7 contributors for this article] (2024). Acceleration of coastal-retreat rates for high-Arctic rock cliffs on Brøggerhalvøya, Svalbard, over the past decade. Earth Surface Dynamics. ISSN 2196-6311. 12(5), p. 1049–1070. doi: 10.5194/esurf-12-1049-2024. Full text in Research Archive Show summary

  In many Arctic regions, marine coastlines change rapidly in our currently warming climate. In contrast, coastal rock cliffs on Svalbard are considered to be relatively stable. Long-term trends of coastal-retreat rates for rock cliffs on Svalbard remain unknown, but quantifying them could improve our understanding of coastal dynamics in the Canadian Arctic Archipelago. This study presents coastal-retreat rates for rock cliffs along several kilometres of Brøggerhalvøya, Svalbard. The analysis relies on high-resolution orthoimages from 1970, 1990, 2010, and 2021. The data are corroborated by high-precision dGNSS (differential Global Navigation Satellite System) measurements obtained along selected segments of the coastline. Our analysis reveals statistically significant acceleration in coastal-retreat rates across Brøggerhalvøya between 2010 and 2021. The northeast-facing coastline features fairly stable conditions, with retreat rates of 0.04 ± 0.06 m a−1 (1970–1990; calculated retreat rate ± the corresponding measurement uncertainty), 0.04 ± 0.04 m a−1 (1990–2010), and 0.06 ± 0.08 m a−1 (2010–2021). Along the southwest-facing coastline, higher retreat rates of 0.26 ± 0.06 m a−1 (1970–1990), 0.24 ± 0.04 m a−1 (1990–2010), and 0.30 ± 0.08 m a−1 (2010–2021) were calculated. For the most recent decade, this corresponds to an increase of 50 % for the northeast-facing coastline and an increase of 25 % for the southwest-facing coastline. Furthermore, for the northeast-facing coastline, the proportion of the coastline affected by erosion increased from 47 % (1970–1990) to 65 % (2010–2021), while it stayed consistently above 90 % for the southwest-facing coastline. The recent acceleration in retreat rates coincides with increasing storminess and retreating sea ice, factors that can enhance coastal erosion.

• Lilleøren, Karianne Staalesen; Etzelmüller, Bernd; Rouyet, Line; Eiken, Trond; Slinde, Gaute Aasen & Hilbich, Christin (2022). Transitional rock glaciers at sea level in northern Norway. Earth Surface Dynamics. ISSN 2196-6311. 10(5), p. 975–996. doi: 10.5194/esurf-10-975-2022. Full text in Research Archive Show summary

  Rock glaciers are geomorphological expressions of permafrost. Close to sea level in northernmost Norway, in the subarctic Nordkinn peninsula, we have observed several rock glaciers that appear to be active now or were active in the recent past. Active rock glaciers at this elevation have never before been described in Fennoscandia, and they are outside the climatic limits of present-day permafrost according to models. In this study, we have investigated whether or not these rock glaciers are active under the current climate situation. We made detailed geomorphological maps of three rock glacier areas in Nordkinn and investigated the regional ground dynamics using synthetic aperture radar interferometry (InSAR). One of the rock glaciers, namely the Ivarsfjorden rock glacier, was investigated in more detail by combining observations of vertical and horizontal changes from optical images acquired by airborne and terrestrial sensors and terrestrial laser scans (TLSs). The subsurface of the same rock glacier was investigated using a combination of electrical resistivity tomography (ERT) and refraction seismic tomography (RST). We also measured ground surface temperatures between 2016 and 2020, complemented by investigations using an infrared thermal camera, and a multi-decadal climatic analysis. We mapped the rock glaciers in the innermost parts of Store and Lille Skogfjorden as relict, while the more active ones are in the mouths of both fjords, fed by active talus in the upper slopes. Several of the rock glaciers cross over both the Younger Dryas shoreline (25 m a.s.l.) and the Early to Mid-Holocene shoreline at 13 m a.s.l. Both InSAR and optical remote sensing observations reveal low yearly movement rates (centimetres to millimetres per year). The ERT and RST suggest that there is no longer permafrost and ground ice in the rock glacier, while temperature observations on the front slope indicate freezing conditions also in summer. Based on the in situ temperature measurements and the interpolated regional temperature data, we show that the mean annual air temperature (MAAT) of the region has risen by 2 ∘C since the late 19th century to about 1.5 ∘C in the last decade. MAATs below 0 ∘C 100–150 years ago suggest that new rock glacier lobes may have formed at the end of the Little Ice Age (LIA). These combined results indicate that the Nordkinn rock glaciers are transitioning from active to relict stages. The study shows that transitional rock glaciers are still affected by creep, rock falls, snow avalanches, etc., and are not entirely dynamically dead features. Our contrasting results concerning permafrost presence and rock glacier activity show the importance of a multi-methodological approach when investigating slope processes in the edge zones of permafrost influence.

• Morris, Richard Ashley; Moholdt, Geir; Gray, Laurence; Schuler, Thomas & Eiken, Trond (2022). CryoSat-2 interferometric mode calibration and validation: A case study from the Austfonna ice cap, Svalbard. Remote Sensing of Environment. ISSN 0034-4257. 269. doi: 10.1016/j.rse.2021.112805. Full text in Research Archive Show summary

  Satellite radar altimetry is widely used to measure glacier and ice sheet elevation changes, but can suffer from uncertainties related to geolocation and signal penetration. The unique capabilities of ESA's CryoSat-2 allow for accurate geolocation but impacts from signal penetration persist. This study uses surface elevations from Global Navigation Satellite System and airborne laser transects over the Austfonna ice cap, Svalbard, to measure the elevation bias of CryoSat-2 Point-of-closest-approach (POCA) and swath points, and to provide validation for estimates derived through the application of a least-squares plane-fit algorithm to these data. The mean elevation bias of swath points varies between 1 and 1.5 m of penetration, which is close to observed winter snow depths. Histograms of POCA elevation bias for the applied leading-edge retracker peak near the surface, with a distribution skewed towards the sub-surface. At the onset of surface melt, surface scattering dominates backscatter, and penetration reduces. This results in spurious peaks in derived elevation and mass change time series. In spite of this seasonal variability in elevation bias, the validation dataset demonstrates that the CryoSat-2 estimates are robust on multi-year timescales. The transition from volume to surface scattering suggests the potential to estimate yearly snowpack thickness.

• Martin, Leo Celestin Paul; Nitzbon, Jan; Scheer, Johanna; Aas, Kjetil Schanke; Eiken, Trond & Langer, Moritz [Show all 9 contributors for this article] (2021). Lateral thermokarst patterns in permafrost peat plateaus in northern Norway. The Cryosphere. ISSN 1994-0416. 15(7), p. 3423–3442. doi: 10.5194/tc-15-3423-2021. Full text in Research Archive Show summary

  Subarctic peatlands underlain by permafrost contain significant amounts of organic carbon. Our ability to quantify the evolution of such permafrost landscapes in numerical models is critical for providing robust predictions of the environmental and climatic changes to come. Yet, the accuracy of large-scale predictions has so far been hampered by small-scale physical processes that create a high spatial variability of thermal surface conditions, affecting the ground thermal regime and thus permafrost degradation patterns. In this regard, a better understanding of the small-scale interplay between microtopography and lateral fluxes of heat, water and snow can be achieved by field monitoring and process-based numerical modeling. Here, we quantify the topographic changes of the Šuoššjávri peat plateau (northern Norway) over a three-year period using drone-based repeat high-resolution photogrammetry. Our results show thermokarst degradation is concentrated on the edges of the plateau, representing 77 % of observed subsidence, while most of the inner plateau surface exhibits no detectable subsidence. Based on detailed investigation of eight zones of the plateau edge, we show that this edge degradation corresponds to an annual volume change of 0.13±0.07 m3 yr−1 per meter of retreating edge (orthogonal to the retreat direction). Using the CryoGrid3 land surface model, we show that these degradation patterns can be reproduced in a modeling framework that implements lateral redistribution of snow, subsurface water and heat, as well as ground subsidence due to melting of excess ice. By performing a sensitivity test for snow depths on the plateau under steady-state climate forcing, we obtain a threshold behavior for the start of edge degradation. Small snow depth variations (from 0 to 30 cm) result in highly different degradation behavior, from stability to fast degradation. For plateau snow depths in the range of field measurements, the simulated annual volume changes are broadly in agreement with the results of the drone survey. As snow depths are clearly correlated with ground surface temperatures, our results indicate that the approach can potentially be used to simulate climate-driven dynamics of edge degradation observed at our study site and other peat plateaus worldwide. Thus, the model approach represents a first step towards simulating climate-driven landscape development through thermokarst in permafrost peatlands.

• Pilø, Lars Holger; Barrett, James; Eiken, Trond; Finstad, Espen; Grønning, Sunniva & Martinsen, Julian Robert Post [Show all 10 contributors for this article] (2020). Interpreting archaeological site-formation processes at a mountain ice patch: A case study from Langfonne, Norway. The Holocene. ISSN 0959-6836. 31(3), p. 1–14. doi: 10.1177/0959683620972775. Full text in Research Archive Show summary

  In the context of global warming, ice patches are increasingly important foci of high-elevation archaeology. Langfonne in Jotunheimen, central southern Norway, is uniquely suited to provide a window onto site formation processes and taphonomy in this novel archaeological setting. Here the site record from systematic survey includes the largest number of arrows, bones and antlers from a single ice patch worldwide. Combining data from these finds with the results of glaciological investigations provides an opportunity to interpret the influence of archaeological site formation processes and taphonomy on chronological and spatial patterning. It is inferred that the spatial patterning of artefacts at Langfonne is partly a result of displacement by ice movement, meltwater and other natural processes. Nevertheless, the finds yield information regarding past hunting practices and the extent of ice at different times. An early cluster of finds from c.6000 cal yr BP may result from ice deformation which has brought early objects to the surface. The number of arrows increases from c. 1700 cal yr BP onwards, peaking around c.1200 cal yr BP. Artefacts from this period show a wide spatial distribution indicating both the preferential survival of more recent finds and that they were lost when the ice patch was large. Based on comparison with the chronology of natural bone and antler samples from the site, the greater number of finds of this date may also reflect a period of increased hunting.

• Böhme, Martina; Hermanns, Reginald; Gosse, John C; Hilger, Paula; Eiken, Trond & Lauknes, Tom Rune [Show all 7 contributors for this article] (2019). Comparison of monitoring data with paleo–slip rates: Cosmogenic nuclide dating detects acceleration of a rockslide. Geology. ISSN 0091-7613. 47(4), p. 339–342. doi: 10.1130/G45684.1. Full text in Research Archive
• Galland, Olivier; Spacapan, Juan Bautista; Rabbel, Ole; Mair, Karen; Soto, Frederico Gonzalez & Eiken, Trond [Show all 8 contributors for this article] (2019). Structure, emplacement mechanism and magma-flow significance of igneous fingers ? Implications for sill emplacement in sedimentary basins. Journal of Structural Geology. ISSN 0191-8141. 124, p. 120–135. doi: 10.1016/j.jsg.2019.04.013. Full text in Research Archive Show summary

  Field and seismic observations show that numerous sills exhibit lobate morphologies. Each lobe corresponds to a distinct igneous segment exhibiting a finger-like shape, the long axis of which is commonly interpreted as a magma-flow indicator. Robust understanding of the emplacement mechanisms of finger-shaped sills, and direct observations supporting finger orientation as magma-flow indicator are lacking. In this paper, we present the results of detailed structural mapping on an exceptional, easily accessible 1-km long outcrop in the Neuquén Basin, Argentina, that exhibits a sill, its contacts and the structures in the finely layered sedimentary host rock. We show that the sill is made of distinct segments that grew, inflated or coalesced. We also demonstrate that the fingers were emplaced according to the viscoelastic fingering or viscous indenter models, with no field evidence of tensile elastic fracture mechanism as commonly assumed in mechanical models of sill emplacement. We identified new structural criteria at the intrusion's contacts for inferring magma flow direction during the magma emplacement. Our small-scale structural observations carried out on a seismic-scale outcrop have the potential to considerably aid the structural interpretation of seismic data imaging igneous sills, i.e. to fill the standard gap between outcrop-scale field observations and seismic-scale geophysical data.

• Ødegård, Rune Strand; Nesje, Atle; Isaksen, Ketil; Andreassen, Liss Marie; Eiken, Trond & Margit, Schwikowski [Show all 7 contributors for this article] (2017). Climate change threatens archaeologically significant ice patches: insights into their age, internal structure, mass balance and climate sensitivity. The Cryosphere. ISSN 1994-0416. 11, p. 17–32. doi: 10.5194/tc-11-17-2017. Full text in Research Archive
• Penna, Ivanna M.; Böhme, Martina; Hermanns, Reginald; Eiken, Trond & Dehls, John (2017). Large-Scale Rockslope Deformations in Sogn Og Fjordane County (Norway). In Sassa, Kyoji; Mikoš, Matjaž & Yin, Yueping (Ed.), Advancing Culture of Living with Landslides: Volume 1 ISDR-ICL Sendai Partnerships 2015-2025. Springer Publishing Company. ISSN 9783319594699. p. 601–606. doi: 10.1007/978-3-319-53485-5_69. Full text in Research Archive Show summary

  This volume contains peer-reviewed papers from the Fourth World Landslide Forum organized by the International Consortium on Landslides (ICL), the Global Promotion Committee of the International Programme on Landslides (IPL), University of Ljubljana (UL) and Geological Survey of Slovenia in Ljubljana, Slovenia from May 29 to June 2, 2017.

• Schleier, Markus; Hermanns, Reginald Leonhard Manfred; Krieger, Ingvar; Oppikofer, Thierry; Eiken, Trond & Rønning, Jan Steinar [Show all 7 contributors for this article] (2016). Gravitational reactivation of a pre-existing post-Caledonian fault system: the deep-seated gravitational slope deformation at Middagstinden, western Norway. Norsk Geologisk Tidsskrift. ISSN 0029-196X. 96(3), p. 201–222. doi: 10.17850/njg96-3-03. Full text in Research Archive Show summary

  The origin of linear features in mountain terrain that form distinct vertical steps is generally not obvious and has been discussed to be related to either tectonic faulting or gravitational slope deformation. A strong geomorphological lineament running oblique to the slope and forming a convex step in the topography is located on the mountain Middagstinden just west of the valley Innfjorddalen, western Norway. In previous studies this lineament has been interpreted to be the surface expression of a Holocene reverse fault previously called the Berill Fault, indicating the first evidence for neotectonic faulting in southern Norway. Now, detailed structural field mapping has revealed the existence of a set of normal fault planes striking subparallel to this lineament and to the main extensional faults associated with the Caledonian collapse. Electric resistivity tomography (ERT) profiles of the valley floor and excavated parallel trenches confirm the regional extent of the fault, but the sediments observed in the trenches do not indicate any Holocene activity. Furthermore, the lineament is a limiting structure of a large rock-slope instability. Kinematic feasibility tests based on structural field measurements indicate wedge failure along the intersection of the fault and the local foliation. However, this intersection line is not exposed on the slope surface. Hence, simple wedge or translational sliding along the slope is not feasible, except in its uppermost part. Both the displacements observed by differential global navigation satellite system (dGNSS) surveys and the geomorphological characteristics, for instance, counterscarps, superficial mass movements, coherent slide blocks and slope bulging, indicate complex deformation mechanisms. The deformation evidently changed along the slope in type and degree including planar sliding in the uppermost part, potentially large wedge sliding in the middle part, and incremental internal deformation in a direction out of the slope in the lower part. The complex kinematics and geomorphological characteristics account for the definition of a deep-seated gravitational slope deformation (DSGSD). Furthermore, the findings reveal that the geomorphological lineament is of gravitational origin and not neotectonic. It has formed by a reactivation of the pre-existing, Caledonian, normal fault system due to the DSGSD, and is hence an example of pseudotectonics ('apparent reverse fault').

• Böhme, Martina; Bunkholt, Halvor S.S.; Oppikofer, Thierry; Dehls, John F.; Hermanns, Reginald Leonhard Manfred & Eriksen, Harald Øverli [Show all 8 contributors for this article] (2016). Using 2D InSAR, dGNSS and structural field data to understand the deformation mechanism of the unstable rock slope Gamanjunni 3, northern Norway. In Aversa, Stefano; Cascini, Laonardo; Picarelli, Luciano & Scavia, Claudio (Ed.), Landslides and Engineered Slopes. Experience, Theory and Practice - Proceedings of the 12th International Symposium on Landslides. CRC Press. ISSN 9781138029880. p. 443–449. doi: 10.1201/b21520-45. Full text in Research Archive
• Rulke, Axel; Dietrich, Reinhard; Capra, Alessandro; Cisak, Jan; Dongchen, E & Eiken, Trond [Show all 20 contributors for this article] (2015). The antarctic regional GPS network densification: Status and results. International Association of Geodesy Symposia. ISSN 0939-9585. 143, p. 133–139. doi: 10.1007/1345_2015_79. Full text in Research Archive
• Dehls, John F.; Lauknes, Tom Rune; Hermanns, Reginald; Bunkholt, Halvor S.S.; Grydeland, Tom & Larsen, Yngvar [Show all 8 contributors for this article] (2014). Use of Satellite and Ground Based InSAR in Hazard Classification of Unstable Rock Slopes. In Sassa, Kyoji; Canuti, Paolo & Yin, Yueping (Ed.), Landslide Science for a Safer Geoenvironment. Springer. ISSN 9783319050492. p. 389–392. doi: 10.1007/978-3-319-05050-8_60. Full text in Research Archive
• Sund, Monica; Lauknes, Tom Rune & Eiken, Trond (2014). Surge dynamics in the Nathorstbreen glacier system, Svalbard. The Cryosphere. ISSN 1994-0416. 8(2), p. 623–638. doi: 10.5194/tc-8-623-2014. Full text in Research Archive
• Booth, Adam M.; Dehls, John; Eiken, Trond; Fischer, Luzia; Hermanns, Reginald L. & Oppikofer, Thierry (2014). Integrating diverse geologic and geodetic observations to determine failure mechanisms and deformation rates across a large bedrock landslide complex: the Osmundneset landslide, Sogn og Fjordane, Norway. Landslides. Journal of the International Consortium on Landslides. ISSN 1612-510X. 12(4), p. 745–756. doi: 10.1007/s10346-014-0504-y. Full text in Research Archive
• Böhme, Martina; Hermanns, Reginald L.; Oppikofer, Thierry; Fischer, Luzia; Bunkholt, Halvor S.S. & Eiken, Trond [Show all 11 contributors for this article] (2013). Analyzing complex rock slope deformation at Stampa, western Norway, by integrating geomorphology, kinematics and numerical modeling. Engineering Geology. ISSN 0013-7952. 154, p. 116–130. doi: 10.1016/j.enggeo.2012.11.016. Full text in Research Archive Show summary

  The unstable rock slope, Stampa, above the village of Flåm, Norway, shows signs of both active and postglacial gravitational deformation over an area of 11 km2. Detailed structural field mapping, annual differential Global Navigation Satellite System (GNSS) surveys, as well as geomorphic analysis of high-resolution digital elevation models based on airborne and terrestrial laser scanning indicate that slope deformation is complex and spatially variable. Numerical modeling was used to investigate the influence of former rockslide activity and to better understand the failure mechanism. Field observations, kinematic analysis and numerical modeling indicate a strong structural control of the unstable area. Based on the integration of the above analyses, we propose that the failure mechanism is dominated by (1) a toppling component, (2) subsiding bilinear wedge failure and (3) planar sliding along the foliation at the toe of the unstable slope. Using differential GNSS, 18 points were measured annually over a period of up to 6 years. Two of these points have an average yearly movement of around 10 mm/year. They are located at the frontal cliff on almost completely detached blocks with volumes smaller than 300,000 m3. Large fractures indicate deep-seated gravitational deformation of volumes reaching several 100 million m3, but the movement rates in these areas are below 2 mm/year. Two different lobes of prehistoric rock slope failures were dated with terrestrial cosmogenic nuclides. While the northern lobe gave an average age of 4,300 years BP, the southern one resulted in two different ages (2,400 and 12,000 years BP), which represent most likely multiple rockfall events. This reflects the currently observable deformation style with unstable blocks in the northern part in between Joasete and Furekamben and no distinct blocks but a high rockfall activity around Ramnanosi in the south. With a relative susceptibility analysis it is concluded that small collapses of blocks along the frontal cliff will be more frequent. Larger collapses of free-standing blocks along the cliff with volumes >100,000 m3, thus large enough to reach the fjord, cannot be ruled out. A larger collapse involving several million m3 is presently considered of very low likelihood.

• Eiken, Trond & Sund, Monica (2012). Photogrammetric methods applied to Svalbard glaciers: accuracies and challenges. Polar Research. ISSN 0800-0395. 31. doi: 10.3402/polar.v31i0.18671. Full text in Research Archive
• Isaksen, Ketil; Ødegård, Rune Strand; Etzelmuller, Bernd; Hilbich, Christin; Hauck, Christian & Farbrot, Herman [Show all 9 contributors for this article] (2011). Degrading Mountain Permafrost in Southern Norway: Spatial and Temporal Variability of Mean Ground Temperatures, 1999–2009. Permafrost and Periglacial Processes. ISSN 1045-6740. 22(4), p. 361–377. doi: 10.1002/ppp.728. Full text in Research Archive Show summary

  A ten-year record (1999–2009) of annual mean ground surface temperatures (MGSTs) and mean ground temperatures (MGTs) was analysed for 16 monitoring sites in Jotunheimen and on Dovrefjell, southern Norway. Warming has occurred at sites with cold permafrost, marginal permafrost and deep seasonal frost. Ongoing permafrost degradation is suggested both by direct temperature monitoring and indirect geophysical surveys. An increase in MGT at 6.6–9.0-m depth was observed for most sites, ranging from ~0.015 to ~ 0.095°C a-1. The greatest rate of temperature increase was for sites having MGTs slightly above 0°C. The lowest rate of increase was for marginal permafrost sites that are affected by latent heat exchange close to 0°C. Increased snow depths and an increase in winter air temperatures appear to be the most important factors controlling warming observed over the ten-year period. Geophysical surveys performed in 1999 to delineate the altitudinal limit of mountain permafrost were repeated in 2009 and 2010 and indicated the degradation of some permafrost over the intervening decade.

• Moholdt, Geir; Hagen, Jon Ove Methlie; Eiken, Trond & Schuler, Thomas (2010). Geometric changes and mass balance of the Austfonna ice cap, Svalbard. The Cryosphere. ISSN 1994-0416. 4, p. 21–34. doi: 10.1785/gssrl.81.1.76. Full text in Research Archive
• Ridefelt, Hanna; Boelhouwers, Jan & Eiken, Trond (2009). Measurement of solifluction rates using multi-temporal aerial photography. Earth Surface Processes and Landforms. ISSN 0197-9337. 34(5), p. 725–737. doi: 10.1002/esp.1773. Full text in Research Archive
• Sund, Monica; Eiken, Trond; Hagen, Jon Ove Methlie & Kääb, Andreas Max (2009). Svalbard surge dynamics derived from geometric changes. Annals of Glaciology. ISSN 0260-3055. 50(52), p. 50–60. Full text in Research Archive
• Dunse, Thorben; Schuler, Thomas; Hagen, Jon Ove Methlie; Eiken, Trond; Brandt, Ola & Høgda, Kjell Arild (2009). Recent fluctuations in the extent of the firn area of Austfonna, Svalbard, inferred from GPR. Annals of Glaciology. ISSN 0260-3055. 50(50), p. 155–162. Full text in Research Archive Show summary

  ABSTRACT. In spring during 2004–07 we conducted ground-penetrating radar (GPR) measurements on the Austfonna ice cap, Svalbard, with the original aim of mapping the thickness and distribution of winter snow. Here, we further exploit the information content of the data and derive a multi-year sequence of glacier-facies distribution that provides valuable spatial information about the total surface mass balance (SMB) of the ice cap, beyond the usually evaluated winter balance. We find that following an initial decrease in the extent of the firn area (2003–04), the firn line lowered within two subsequent years by ∼40–100m elevation in the north and west and 150–230m in the south and east of the ice cap, corresponding to a lateral expansion of the firn area along the profiles by up to 7.3 and 13.3 km, respectively. The growth of the firn area is in line with stake measurements from Etonbreen that indicate a trend towards less negative SMB over the corresponding period.

• Sund, Monica; Eiken, T.; Hagen, J.O. & Kääb, A. (2009). Svalbard surge dynamics derived from geometric changes. Annals of Glaciology. ISSN 0260-3055. 50(52), p. 50–60. doi: 10.3189/172756409789624265. Full text in Research Archive Show summary

  Geometric changes on a sample of Svalbard glaciers were studied using subtraction of repeat digital terrain models to determine early surge-stage dynamics. Changes in surface features were also analyzed. A number of new surges were found for glaciers not known to have surged previously. The surge development could be followed through three stages, of which the first two had not been previously described in Svalbard. The first two stages are mainly identified from glacier thickness changes and showed little visual evidence. In stage 1, initial surface lowering was found in the upper part of the glacier, followed by a thickening further down-glacier in stage 2. Stage 3 represents the period of well-developed surge dynamics that is usually reported. Some surges ceased at stage 2 as a partial surge and never developed into a fully active surge. These partial surges could be misinterpreted as rapid response to climate change. The results of this study further support previous findings that the majority of Svalbard glaciers are of surge type.

• Ganerød, Guri Venvik; Grøneng, G.; Rønning, J.S.; Dalsegg, E.; Elvebakk, H & Tønnesen, Jan Fredrik [Show all 10 contributors for this article] (2008). Geological model of the Åknes Rockslide, western Norway. Engineering Geology. ISSN 0013-7952. 102, p. 1–18. Full text in Research Archive
• Ganerød, Guri Venvik; Grøneng, Guro; Rønning, Jan Steinar; Dalsegg, Einar; Elvebakk, Harald & Tønnesen, Jan Fredrik [Show all 10 contributors for this article] (2008). Geological model of the Åknes rockslide, western Norway. Engineering Geology. ISSN 0013-7952. 102(1-2), p. 1–18. doi: 10.1016/j.enggeo.2008.01.018. Full text in Research Archive
• Ganerød, Guri Venvik; Grøneng, G.; Rønning, J.S.; Dalsegg, E.; Elvebakk, H. & Tønnesen, J.F. [Show all 10 contributors for this article] (2008). Geological model of the Aknes rockslide, western Norway. Engineering Geology. ISSN 0013-7952. 102(1-2), p. 1–18. doi: 10.1016/j.enggeo.2008.01.018. Full text in Research Archive
• Farbrot, Herman; Etzelmuller, Bernd; Gudmundsson, August; Humlum, Ole; Kellerer-Pirklbauer, Andreas & Eiken, Trond [Show all 7 contributors for this article] (2007). Rock glaciers and permafrost in Tröllaskagi, northern Iceland. Zeitschrift für Geomorphologie. ISSN 0372-8854. 51, p. 1–16. doi: 10.1127/0372-8854/007/0051S2-0001. Full text in Research Archive
• Farbrot, Herman; Etzelmuller, Bernd; Schuler, Thomas; Guomundsson, A; Eiken, Trond & Humlum, Ole [Show all 7 contributors for this article] (2007). Thermal characteristics and impact of climate change on mountain permafrost in Iceland. Journal of Geophysical Research (JGR). ISSN 0148-0227. 112(F03S90). doi: 10.1029/2006JF000541. Full text in Research Archive
• Wangensteen, Bjørn; Eiken, Trond; Odegard, RS & Sollid, Johan Ludvig (2007). Measuring coastal cliff retreat in the Kongsfjorden area, Svalbard, using terrestrial photogrammetry. Polar Research. ISSN 0800-0395. 26, p. 14–21. doi: 10.1111/j.1751-8369.2007.00002.x. Full text in Research Archive
• Taurisano, Andrea; Schuler, Thomas; Hagen, Jon Ove Methlie; Eiken, Trond; Loe, Even & Melvold, Kjetil [Show all 7 contributors for this article] (2007). The distribution of snow accumulation across the Austfonna ice cap, Svalbard: direct measurements and modelling. Polar Research. ISSN 0800-0395. 26, p. 7–13. doi: 10.1111/j.1751-8369.2007.00004.x. Full text in Research Archive Show summary

  We present an analysis of the spatial variability in the snow accumulation on the Austfonna ice cap in Svalbard, Norway, based on the results of field investigations conducted in the spring of 1999, 2004 and 2005. During the campaigns ground penetrating radar measurements at 500 and 800 MHz were collected along profiles, along with additional manual snow sounding and pit stratigraphy work. The analysis of the data reveals a consistent pattern in the spatial distribution of the snow accumulation over the ice-cap, and therefore enables the compilation of a multiple regression model of the snow distribution across the ice cap. Once validated, the results of the model complement the information derived from direct measurements, with an accumulation index for every point on the ice cap, thus enhancing the accuracy of future mass balance studies and dynamic modelling of Austfonna. As very few direct meteorological measurements are performed in the eastern part of Svalbard, the accumulation measurements on the Austfonna ice cap provide valuable integrated information about winter precipitation in this region.

• Schuler, Thomas; Loe, Even; Taurisano, Andrea; Eiken, Trond; Hagen, Jon Ove Methlie & Kohler, Jack (2007). Calibrating a surface mass balance model for the Austfonna ice cap, Svalbard. Annals of Glaciology. ISSN 0260-3055. 46, p. 241–248. Full text in Research Archive
• Wangensteen, Bjørn; Tønsberg, Ole Magnus; Kääb, Andreas Max; Eiken, Trond & Hagen, Jon Ove Methlie (2006). Surface elevation change and high resolution surface velocities for advancing outlets of Jostedalsbreen. Geografiska Annaler: Series A, Physical Geography. ISSN 0435-3676. 88A(1), p. 55–74. Full text in Research Archive
• Wangensteen, Bjørn; Gudmundsson, Agust; Eiken, Trond; Kääb, Andreas Max; Farbrot, Herman & Etzelmuller, Bernd (2006). Surface displacements and surface age estimates for creeping slope landforms in Northern and Eastern Iceland using digital photogrammetry. Geomorphology. ISSN 0169-555X. 80(1-2), p. 59–79. Full text in Research Archive
• Farbrot, Herman; Isaksen, Ketil; Eiken, Trond; Kääb, Andreas Max & Sollid, Johan Ludvig (2005). Composition and internal structures of a rock glacier on the strandflat of western Spitsbergen, Svalbard. Norsk Geografisk Tidsskrift. ISSN 0029-1951. p. 139–148. Full text in Research Archive
• Sund, Monica & Eiken, Trond (2004). Quiescent-phase dynamics and surge history of a polythermal glacier: Hessbreen, Svalbard. Journal of Glaciology. ISSN 0022-1430. 50(171), p. 547–555. Full text in Research Archive
• Odergard, RS; Isaksen, K; Eiken, Trond & Sollid, Johan Ludvig (2003). Terrain analyses and surface velocity measurements of the Hiorthfjellet rock glacier, Svalbard. Permafrost and Periglacial Processes. ISSN 1045-6740. 14, p. 359–365. Full text in Research Archive
• Isaksen, Ketil; Heggem, Eva Solbjørg Flo; Bakkehøi, Steinar; Ødegård, Rune Strand; Eiken, Trond & Etzelmuller, Bernd [Show all 7 contributors for this article] (2003). Mountain permafrost and energy balance on Juvvasshøe, southern Norway, Eigth International Conference on Permafrost, Proceedings. Balkema. p. 467–472. Full text in Research Archive
• Eiken, Trond; Omang, O.C.D. & Øvstedal, O. (2001). A local geoid, in Dronning Mauds Land - The NARE 96/97 Geoid. IGeS Bulletin. ISSN 1128-3955. 11, p. 30–48. Full text in Research Archive
• Pinglot, Jean Francis; Hagen, Jon Ove Methlie; Melvold, Kjetil; Eiken, Trond & Vincent, C. (2001). A mean net accumulation pattern derived from radioactive layers and radar soundings on Austfonna, Nordaustlandet, Svalbard. Journal of Glaciology. ISSN 0022-1430. 47(159), p. 155–166. Full text in Research Archive
• Berthling, Ivar Thoralf; Etzelmuller, Bernd; Eiken, Trond & Sollid, Johan Ludvig (2001). The rock glaciers on Prins Karls Forland, Svalbard (II). The development of internal structures. Permafrost and Periglacial Processes. ISSN 1045-6740. 11, p. 357–369. Full text in Research Archive
• Berthling, Ivar Thoralf; Eiken, Trond & Sollid, Johan Ludvig (2001). Frost heave and thaw consolidation of ploughing boulders in a mid-alpine environment, Finse, southern Norway. Permafrost and Periglacial Processes. ISSN 1045-6740. 12(2), p. 165–177. Full text in Research Archive
• Berthling, Ivar Thoralf; Eiken, Trond & Sollid, Johan Ludvig (2001). Downslope displacement rates of ploughing boulders in a mid-alpine environment: Finse, southern Norway. Geografiska Annaler: Series A, Physical Geography. ISSN 0435-3676. 83A(3), p. 103–116. doi: 10.1111/j.0435-3676.2001.00147.x. Full text in Research Archive
• Berthling, Ivar Thoralf; Eiken, Trond & Sollid, Johan Ludvig (2000). Continuous measurements of solifluction using carrier-phase differential GPS. Norsk Geografisk Tidsskrift. ISSN 0029-1951. 54(4), p. 182–185. Full text in Research Archive Show summary

  In this research note, we test the potential for use of differential carrier-phase GPS measurements (DGPS) for continuous recording of the slow mass wasting occurring in solifluction. DGPS is shown to be capable of yielding records of high temporal resolution and accuracy.

• Isaksen, Ketil; Ødegård, Rune Strand; Eiken, Trond & Sollid, Johan Ludvig (2000). Composition, flow and development of two tounge-shaped rock glaciers in the permafrost of Svalbard. Permafrost and Periglacial Processes. ISSN 1045-6740. 11, p. 241–257. Full text in Research Archive Show summary

  Two tongue-shaped rock glaciers on Svalbard have been investigated. The results of surface velocity measurements reveal horizontal surface velocities of 0.05-0.10 m a-1. The oldest surface of these rock glaciers is roughly estimated to 4000 yr. based on a tentative dating by calculation of the length-surface velocity ratio (LSVR). With respect to rock glacier dynamics and long term initial development of their particular forms, it is likely that the rock glaciers started to develop at the onset of the Holocene. DC-resistivity results indicate an inner structure with an 20-35 m thick high-resistivity ice-rich layer (100-900 k0m) laying on a lower resistive layer (5-70 k0m) interpreted as ice-saturated sediments. Ground penetrating radar (f=50MHz) shows clear reflection horizons or layers along the longitudinal profile of the rock glacier. In a short zone at the rear of the profile, the layers are orientated parallel or slanting downwards in relation to the rock glacier surface. In the frontal part the layers slant upwards. The orientation of the layers changes in a narrow transition zone. The layers can be recognized clearly down to 15-20 m depth. They are interpreted to represent sediments supersaturated with ice alternating with layers of rockslide debris. The supersaturated layers are interpreted as snowdrifts later covered with debris from rockslides. Repeated mass movement events result in aggregational ice layers gradually becoming part of the creeping rock glacier. This mechanism is assumed to be the most important accumulation process for the development of the investigated rock glaciers.

• Hagen, Jon Ove Methlie; Melvold, Kjetil; Eiken, Trond; Isaksson, Elisabeth & Lefauconnier, Bernard (1999). Mass balance methods on Kongsvegen, Svalbard. Geografiska Annaler: Series A, Physical Geography. ISSN 0435-3676. 81 A (4), p. 593–601. Full text in Research Archive
• Berthling, Ivar Thoralf; Etzelmuller, Bernd; Eiken, Trond & Sollid, Johan Ludvig (1998). Rock glaciers on Prins Karls Forland, Svalbard. I: Internal structure, flow velocity and morphology. Permafrost and Periglacial Processes. ISSN 1045-6740. 9, p. 135–145. Full text in Research Archive
• Berthling, Ivar Thoralf; Etzelmuller, Bernd; Eiken, Trond & Sollid, Johan Ludvig (1998). The rock glaciers on Prins Karls Forland, Svalbard (I). Internal structure, flow velocity and morphometry. Permafrost and Periglacial Processes. ISSN 1045-6740. 9, p. 135–145. Full text in Research Archive
• Eiken, Trond; Hagen, Jon Ove Methlie & Melvold, Kjetil (1997). Kinematic GPS survey of geometry changes on Svalbard glaciers. Annals of Glaciology. ISSN 0260-3055. 24, p. 157–163. Full text in Research Archive
• Eiken, Trond (1994). Mapping the most remote islands on earth. GIM. Geodetical information magazine. ISSN 0928-1436. 8(3), p. 25–28. Full text in Research Archive

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• Ødegård, Rune Strand; Nesje, Atle; Isaksen, Ketil; Andreassen, Liss Marie & Eiken, Trond (2016). Archeologically significant cold ice patches in southern Norway - an indicator of mountain permafrost. Full text in Research Archive
• Dunse, Thorben; Schuler, Thomas; Hagen, Jon Ove Methlie & Eiken, Trond (2013). Ground-based monitoring of snowcover, firn area and glacier facies of Austfonna, Svalbard, to validate and improve PolarWRF climate simulations. Full text in Research Archive
• Schuler, Thomas; Dunse, Thorben; Eiken, Trond & Hagen, Jon Ove Methlie (2013). Considering orographic enhancement to downscale precipitation: resolving the accumulation asymmetry and deriving a 55 year accumulation history of Austfonna, Svalbard. Full text in Research Archive
• Schuler, Thomas; Dunse, Thorben; Eiken, Trond; Hagen, Jon Ove Methlie; Moholdt, Geir & Østby, Torbjørn (2011). A framework for modeling climatic mass balance from reanalysis data - Austfonna, Svalbard. Full text in Research Archive
• Hagen, Jon Ove Methlie; Dunse, Thorben; Eiken, Trond; Moholdt, Geir; Nuth, Christopher & Schuler, Thomas (2010). GLACIODYN - The response of Arctic glaciers to global warming. Full text in Research Archive
• Schuler, Thomas; Dunse, Thorben; Eiken, Trond; Hagen, Jon Ove Methlie; Moholdt, Geir & Nuth, Christopher (2010). A surface mass balance history of Austfonna, Svalbard, derived from reanalysis data. Full text in Research Archive
• Isaksen, Ketil; Ødegård, Rune Strand; Etzelmuller, Bernd; Farbrot, Herman; Hipp, Tobias Florian & Eiken, Trond [Show all 8 contributors for this article] (2010). Characteristics and controlling factors of warming mountain permafrost in Jotunheimen and Dovrefjell, southern Norway. Full text in Research Archive
• Sund, Monica & Eiken, Trond (2010). Recent surges on Blomstrandbreen, Comfortlessbreen and Nathorstbreen, Svalbard. Journal of Glaciology. ISSN 0022-1430. 56(195), p. 182–184. Full text in Research Archive
• Moholot, Geir; Hagen, Jon Ove Methlie & Eiken, Trond (2008). Geometric changes of Austfonna ice cap. Full text in Research Archive
• Hagen, Jon Ove Methlie; Eiken, Trond; Schuler, Thomas; Dunse, Thorben; Melvold, Kjetil & Moholot, Geir [Show all 9 contributors for this article] (2008). Recent changes in surface mass balance of the Austfonna ice cap, Svalbard. Full text in Research Archive
• Dunse, Thorben; Schuler, Thomas; Hagen, Jon Ove Methlie; Eiken, Trond; Moholot, Geir & Taurisano, Andrea [Show all 8 contributors for this article] (2008). Glacier facies transitions on Austfonna, Svalbard, derived from ground-penetrating radar. Full text in Research Archive
• Schuler, Thomas; Dunse, Thorben; Eiken, Trond; Hagen, Jon Ove Methlie; Moholot, Geir & Taurisano, Andrea (2008). The accumulation pattern of Austfonna, Svalbard. Full text in Research Archive
• Sund, Monica; Eiken, Trond; Hagen, Jon Ove Methlie; Kääb, Andreas Max; Schuler, Thomas & Müller, Karsten [Show all 8 contributors for this article] (2008). Recent surge activity in southern Spitsbergen. Full text in Research Archive
• Moholot, Geir; Dunse, Thorben; Eiken, Trond; Hagen, Jon Ove Methlie; Schuler, Thomas & Brandt, Ola (2008). Geodetic mass balance of Vestfonna, Austfonna and Kvitøyjøkulen ice caps since 1983. Full text in Research Archive
• Schuler, Thomas; Dunse, Thorben; Eiken, Trond; Hagen, Jon Ove Methlie; Moholot, Geir & Nuth, Christopher (2008). A 50 year accumulation history of Austfonna, Svalbard. Full text in Research Archive
• Ødegård, Rune Strand; Isaksen, Ketil; Sollid, Johan Ludvig & Eiken, Trond (2008). MAGST in Mountain Permafrost, Dovrefjell, Southern Norway, 2001-2006. ?. p. 5–5. Full text in Research Archive Show summary

  A monitoring program to measure ground and air temperatures were started in autumn 2001 in Dovrefjell (62°15¿N, 9°20¿E), a mountainous area in southern Norway. Ground temperatures are measured in a transect from deep seasonal frost at 1039 m a.s.l. to discontinuous mountain permafrost at 1505 m a.s.l. in 11 boreholes 9 m deep. This is the first transect of this type set up in Scandinavia. Preliminary results are presented including measurements at 0.2 m and 8.5 m depth. The collected ground surface temperatures (GST) show pronounced fluctuations and large inter-annual variability. A simple normalization procedure is suggested to relate the observed GST to the reference period 1961-1990. The results suggest that even with an averaging period of 5 years the MAGST could deviate more that 1 ºC from the 30-year average. The period 2001-2006 is generally found to be warmer than the reference period, suggesting thawing permafrost at sites with discontinuous or thin snow cover.

• Dunse, Thorben; Schuler, Thomas Vikhamar; Hagen, Jon Ove Methlie; Eiken, Trond; Moholot, Geir & Melvold, Kjetil (2007). Glacier facies transitions on Austfonna, Svalbard, derived from ground-penetrating radar. Full text in Research Archive
• Dunse, Thorben; Schuler, Thomas Vikhamar; Hagen, Jon Ove Methlie; Eiken, Trond; Melvold, Kjetil & Moholot, Geir (2007). Snow accumulation over Austfonna, northeastern Svalbard, derived by ground-penetrating radar. Full text in Research Archive
• Schuler, Thomas; Loe, Even; Taurisano, Andrea; Eiken, Trond; Hagen, Jon Ove Methlie & Kohler, Jack (2006). A calibrated surface mass balance model for the Austfonna ice cap, Svalbard. Full text in Research Archive
• Hagen, Jon Ove Methlie; Eiken, Trond; Loe, Even; Kohler, Jack; Melvold, Kjetil & Schuler, Thomas [Show all 7 contributors for this article] (2006). More on elevation changes on Austfonna Ice Cap. Full text in Research Archive
• Schuler, Thomas; Eiken, Trond; Hagen, Jon Ove Methlie; Loe, Even; Melvold, Kjetil & Taurisano, Andrea (2006). A surface mass balance model for Austfonna, Svalbard. Full text in Research Archive
• Loe, Even; Eiken, Trond; Hagen, Jon Ove Methlie; Melvold, Kjetil; Schuler, Thomas & Taurisano, Andrea (2006). Energy and mass balance at Etonbreen, Austfonna. Full text in Research Archive
• Hagen, Jon Ove Methlie; Eiken, Trond; Loe, Even; Schuler, Thomas & Taurisano, Andrea (2006). Elevation changes on Austfonna Ice Cap. Full text in Research Archive
• Wangensteen, Bjørn; Guðmundsson, Águst; Eiken, Trond; Kääb, Andreas Max; Farbrot, Herman & Etzelmuller, Bernd (2005). Surface displacements and surface age estimates for creeping slope landforms in Northern Iceland using digital phototgrammetry. Full text in Research Archive
• Wangensteen, Bjørn; Eiken, Trond; Ødegård, Rune Strand & Sollid, Johan Ludvig (2005). Measuring coastal cliff erosion using digital phototgrammetry in the Kongsfjorden area, Svalbard -first results. Full text in Research Archive
• Farbrot, Herman; Etzelmuller, Bernd; Gudmundsson, Agust; Wangensteen, Bjørn; Eiken, Trond & Humlum, Ole (2005). Permafrost boreholes in Iceland. Full text in Research Archive
• Schuler, Thomas; Hagen, Jon Ove Methlie; Eiken, Trond; Loe, Even; Melvold, Kjetil & Kohler, Jack [Show all 7 contributors for this article] (2005). A surface mass balance model for Austfonna, Svalbard. Full text in Research Archive
• Etzelmuller, Bernd; Wangensteen, Bjørn; Gudmundsson, A.; Farbrot, Herman; Humlum, Ole & Eiken, Trond [Show all 7 contributors for this article] (2004). Surface displacement, volume changes and Holocene sediment flux rates for active rock glaciers and moving debris bodies on Iceland - examples from the Tröllaskagi Peninsula, northern Iceland, and Seydisfjordu area, eastern Iceland. Full text in Research Archive
• Farbrot, Herman; Wangensteen, Bjørn; Eiken, Trond; Etzelmuller, Bernd & Humlum, Ole (2004). Permafrost distribution in Iceland and northern Norway. Full text in Research Archive
• Farbrot, Herman; Isaksen, Ketil; Eiken, Trond & Sollid, Johan Ludvig (2004). Internal composition and structures of a complex rock glacier, Nordenskiöldkysten, Svalbard. Full text in Research Archive
• Sollid, Johan Ludvig; Wangensteen, Bjørn; Ødegård, Rune Strand & Eiken, Trond (2004). Measuring coastal cliff erosion by means of terrestrial photogrammetry in the Kongsfjorden area, Svalbard. Full text in Research Archive
• Hagen, Jon Ove Methlie; Eiken, Trond; Kohler, Jack & Melvold, Kjetil (2004). Geometry changes on Svalbard glaciers – mass balance or dynamic response? Full text in Research Archive
• Wangensteen, Bjørn; Guðmundsson, Águst; Eiken, Trond; Kääb, Andreas Max; Farbrot, Herman & Etzelmuller, Bernd (2004). Surface Displacements and Volume Changes for a Debris Covered Glacier and a Moving Debris Body at the Tröllaskagi Peninsula, Northern Iceland, by the use of Digital Photogrammetry. Full text in Research Archive
• Wangensteen, Bjørn; Guðmundsson, Águst; Eiken, Trond; Kääb, Andreas Max; Farbrot, Herman & Etzelmuller, Bernd (2004). Surface displacement, volume change and age estimates for some debris covered glaciers and rock glaciers in northern Iceland using digital photogrammetry. Full text in Research Archive
• Isaksen, Ketil; Heggem, Eva Solbjørg Flo; Bakkehøi, Steinar; Ødegård, Rune Strand; Eiken, Trond & Etzelmuller, Bernd [Show all 7 contributors for this article] (2003). Mountain permafrost and energy balance on Juvvasshøe, southern Norway. Full text in Research Archive
• Wangensteen, Bjørn; Eiken, Trond; Ødegård, Rune Strand & Sollid, Johan Ludvig (2003). Establishing four sites for measuring coastal cliff erosion by means of terrestrial photogrammetry in the Kongsfjorden area, Svalbard. Full text in Research Archive
• Wangensteen, Bjørn; Eiken, Trond; Melvold, Kjetil; Tønsberg, Ole Magnus & Hagen, Jon Ove Methlie (2003). Determining the flow fields of two glacier outlets of the Jostedalsbreen ice cap, Norway, using digital photogrammetry. Full text in Research Archive
• Eiken, Trond & Wangensteen, Bjørn (2002). Velocity measurements on Nigardsbreen by means of cross correlation of orthophotos -first test. Full text in Research Archive
• Wangensteen, Bjørn; Eiken, Trond; Ødegård, Rune Strand & Sollid, Johan Ludvig (2002). Establishing of Four Sites for Measuring Coastal Cliff Erosion by Means of Terrestrial Photogrammetry in the Kongsfjorden Area, Svalbard. Full text in Research Archive
• Wangensteen, Bjørn; Ødegård, Rune Strand; Eiken, Trond & Sollid, Johan Ludvig (2001). Measurements of coastal change in the Russian artic and at Svalbard by means of multi-temporal aerial photographs and digital photogrammetry. Full text in Research Archive
• Eiken, Trond; Omang, Ove Christian Dahl & Øvstedal, Ola (2001). A local geoid in Dronning Maud Land - The NARE 96/97 Geoid. IGeS Bulletin. ISSN 1128-3955. p. 30–48. Full text in Research Archive Show summary

  The main purpose of the present paper is to estimate the orthometric height of the GPS-station at Troll, Dronning Maud Land, Antarctica. Located at approximately 1300 m above sea level Troll has been connected to the GIANT-network, but it's orthometric height remains undetermined. A local geoid has been determined based on gravity-, tidal- and GPS-observations and available gravity anomalies. Information about the ice-thickness has been included in the terrain model. Based on tidal measurements the mean sea level was determined in Jutulgryta, a rift zone in the Fimbulisen ice shelf. Several gravity- and GPS-stations were measured between the two points (Jutulgryta and Troll), a distance of approximately 100 km.

• Berthling, Ivar Thoralf; Eiken, Trond & Sollid, Johan Ludvig (2000). Three dimensional displacements of ploughing boulders at Finse, southern Norway. Full text in Research Archive
• Eiken, Trond; Omang, Ove C. D. & Øvstedal, Ola (1999). A local geoid in Dronning Maud Land. Full text in Research Archive Show summary

  The main purpose of the present paper is to estimate the orthometric height of the GPS-station at Troll, Dronning Maud Land, Antarctica. Located at approximately 1300 m Troll has been connected to the GIANT-network, but it's orthometric height remains undetermined. A local geoid has been determined based on available gravity anomalies and vertical angle mesurements. Information about the ice-thickness has been included in the terrain model. Based on tidal measurements the mean sea level was determined in Jutulgryta, a rift zone in the Fimbulisen ice shelf. Several gravity- and GPS-stations were measured between the two points (Jutulgryta and Troll), a distance of approximately 100 km.

• Berthling, Ivar Thoralf; Eiken, Trond; Etzelmuller, Bernd & Sollid, Johan Ludvig (1997). The relationship between strain and morphology on a solifluction lobe, Finse, southern Norway. Full text in Research Archive

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