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Sailer, R., Bollmann, E., Hoinkes, S., Rieg, L., Sproß, M. and Stötter, J., 2012. Quantification of geomorphodynamics in glaciated and recently deglaciated terrain based on airborne laser scanning data. Geografiska Annaler, Series A: Physical Geography, 94, 17-32. doi:10.1111/j.1468-0459.2012.00456.x ABSTRACT This article highlights the ability of airborne laser scanning (ALS) to detect, map and quantify geomorphological processes in high alpine environments. Since 2001, ALS measurements have been carried out regularly at Hintereisferner (Ötztal Alps, Tyrol, Austria), resulting in a unique data record of 18 ALS flight campaigns. The quantifications of volumetric earth surface changes caused by dead-ice melting, fluvial erosion/deposition, rock-fall activity, gravitational displacements and permafrost degradation in glaciated, recently deglaciated and periglacial terrain is based on the analysis of ALS point clouds (vector data) to preserve the high quality of the data. We present inter-annual, annual and perennial trends of geomorpho-dynamically induced topographic changes. The most significant changes occurred at two dead ice bodies (−0.48 m and −0.24 m respectively per year). At a complex rock fall site, mean annual vertical changes of −0.25 m are observed in the source area, respectively 0.25 m of deposited material in the run-out area. Fluvial erosion processes are connected with subsequent gravitational denudation, reallocation and deposition. Topographic changes caused by fluvial erosion between 2001 and 2009 range from −0.68 m to −1.20 m. Surface elevation increase caused by fluvial accumulation is found to be 0.48 m from 2001 to 2009. Minor annual surface elevation changes (between −0.05 m and −0.10 m a−1) are detected in permafrost areas. Finally, the significance of the process-dependent topographic change rates is assessed, regarding the accuracy of the ALS data, the magnitude of the process, the time lapse between the single ALS-campaigns and disturbing factors (e.g. snow cover). For processes with high magnitudes time lapse rates can be shorter than one year and disturbing factors have only minor influences on the results. In contrast, results of processes with low magnitudes gain relevance with an increasing time lapse between the ALS campaigns, the frequency of flight campaigns and if disturbing factors can be excluded. [ABSTRACT FROM AUTHOR]

Rutzinger, M., Höfle, B. and Kringer, K., 2012. Accuracy of automatically extracted geomorphological breaklines from airborne LiDAR curvature images. Geografiska Annaler: Series A, Physical Geography, 94, 33-42. doi:10.1111/j.1468-0459.2012.00453.x ABSTRACT Geomorphological breaklines are 3D polylines extracted from high-resolution digital terrain models (DTMs), which have manifold applications in geomorphology and related fields. Breaklines are used to maintain and refine the characteristic information on discontinuities in the process of DTM filtering and interpolation. Knowledge about the quality of the derived breaklines is important in order to provide adequate input data for DTM generation, geomorphological feature mapping, and change detection analysis. The spatial accuracy and the classification accuracy of derived breaklines depend on data acquisition settings and processing steps. The critical criteria are the precision and density of the LiDAR point cloud, the resolution and quality of the filtered and interpolated DTM and the target scale breaklines are derived for. In this paper a quantitative method for assessing the quality of derived breaklines, which are extracted from regions with high curvature, is presented. Selected components of the breakline detection workflow are analysed. In addition, the reliability of manually digitized reference lines is investigated. Selected geometric properties such as line length, slope and sinuosity are computed and compared to reference data. The properties are discussed regarding their explanatory power with respect to accuracy and precision. Automatic extraction results strongly differ from manually digitized breaklines. Breaklines from manual digitalization are found to vary in coverage and spatial accuracy and thus reflect always the operator's ability, perception and intention. The advantage of automated extracted breaklines is their reproducibility and adaptability to scale. [ABSTRACT FROM AUTHOR]

Möller, M., Möller, R., Beaudon, É., Mattila, O.-P., Finkelnburg, R., Braun, M., Grabiec, M., Jonsell, U., Luks, B., Puczko, D., Scherer, D. and Schneider, C., 2011. Snowpack characteristics of Vestfonna and De Geerfonna (Nordaustlandet, Svalbard) - a spatiotemporal analysis based on multiyear snow-pit data. Geografiska Annaler, Series A: Physical Geography, 93, 273-285. DOI: 10.1111/j.1468-0459.2011.00440.x ABSTRACT Extensive glaciological field measurements were carried out on the ice cap Vestfonna as well as on the minor ice body De Geerfonna (Nordaustlandet, Svalbard) within the framework of IPY Kinnvika. Field campaigns were conducted during the period 2007-2010 in spring (April/May) and summer (August). In this study we compile and present snow cover information obtained from 22 snow pits that were dug on Vestfonna during this period. Locations are along two transects on the northwestern, land terminating slope of the ice cap, on its central summit, Ahlmann Summit, and at a set of several other locations in the eastern and northern part of the ice cap. Snow-cover information acquired from four snow pits on adjacent De Geerfonna is also incorporated in this study. Field data are analysed regarding snow stratigraphy, snow density, snow hardness and snow temperature. Results reveal mean snow densities of around 400 kg m−3 for the snowpack of Vestfonna with no apparent spatial or interannual variability. A distinctly higher value of more than 450 kg m−3 was obtained for De Geerfonna. A spatial comparison of snow water equivalents above the previous end-of-summer surface serves for obtaining insights into the spatial distribution of snow accumulation across Vestfonna. Altitude was found to be the only significant spatial parameter for controlling snow accumulation across the ice cap. [ABSTRACT FROM AUTHOR]

Coulson, S.J., Fjellberg, A., Snazell, R., Gwiazdowicz, D.J., and Ávila-Jiménez, M.L., 2011. On the Collembola, Araneae and Gamasida from the Kinnvika region of Nordaustlandet, Svalbard. Geografiska Annaler: Series A, Physical Geography, 93, 253-257. DOI: 10.1111/j.1468-0459.2011.00425.x ABSTRACT The Collembola, Araneae and gamasid mite fauna from the vicinity of Kinnvika on the island of Nordaustlandet in the Svalbard archipelago are described. Few records of the invertebrate fauna from this remote and climatically extreme region exist. Twenty-four species of Collembola were identified, of which three were new records for Nordaustlandet. None were new records for Svalbard. In addition, seven species of Araneae, three of which were new records for Nordaustlandet, and five species of gamasid mite, all new to Nordaustlandet, were collected. All invertebrates collected were already known from locations on the west coast of Spitsbergen. These records supplement the scarce current terrestrial invertebrate data for this region and contribute towards the baseline data for this region proposed to become an Arctic environmental reference area. [ABSTRACT FROM AUTHOR]