UAV platforms are nowadays a valuable source of data for inspection, surveillance, mapping and 3D modeling issues. New applications in the short- and close-range domain are introduced, being the UAVs a low-cost alternatives to the classical manned a erial photogrammetry. Rotary or fixed wing UAVs, capable of performing the photogrammetric data acquisition with amateur or SLR digital cameras, can fly in manual, semi-automated and autonomous modes. With a typical photogrammetric pipeline, 3D results like DSM/DTM, contour lines, textured 3D models, vector data, etc. can be produced, in a reasonable automated way. The paper reports the latest developments of UAV image processing methods for photogrammetric applications, mapping and 3D modeling issues. Automation is nowadays necessary and feasible at the image orientation, DSM generation and orthophoto production stages, while accurate feature extraction is still an interactive procedure. New perspectives are also addressed.

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Uav photogrammetry for mapping and 3d modeling - current status and future perspectives -

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Permafrost and climate in Europe: Monitoring and modelling thermal, geomorphological and geotechnical responses

This review paper examines thermal conditions (active layer and permafrost), internal composition (rock and ice components), kinematics and rheology of creeping perennially frozen slopes in cold mountain areas. The aim is to assemble current information about creep in permafrost and rock glaciers from diverse published sources into a single paper that will be useful in studies of the flow and deformation of subsurface ice and their surface manifestations not only on Earth, but also on Mars. Emphasis is placed on quantitative information from drilling, borehole measurements, geophysical soundings, photogrammetry, laboratory experiments, etc. It is evident that quantitative holistic treatment of permafrost creep and rock glaciers requires consideration of: (a) rock weathering, snow avalanches and rockfall, with grain-size sorting on scree slopes; (b) freezing processes and ice formation in scree at sub-zero temperatures containing abundant fine material as well as coarse-grained blocks; (c) coupled thermohydro-mechanical aspects of creep and failure processes in frozen rock debris; (d) kinematics of non-isotropic, heterogeneous and layered, ice-rich permafrost on slopes with long transport paths for coarse surface material from the headwall to the front and, in some cases, subsequent re-incorporation into an advancing rock glacier causing corresponding age inversion at

Permafrost creep and rock glacier dynamics

https://www.uibk.ac.at/geographie/personal/kerschner/larstig-qsr.pdf

Latest Pleistocene and Holocene glacier variations in the European Alps

. The mountain cryosphere of mainland Europe is recognized to have important impacts on a range of environmental processes. In this paper, we provide an overview on the current knowledge on snow, glacier, and permafrost processes, as well as their past, current, and future evolution. We additionally provide an assessment of current cryosphere research in Europe and point to the different domains requiring further research. Emphasis is given to our understanding of climate–cryosphere interactions, cryosphere controls on physical and biological mountain systems, and related impacts. By the end of the century, Europe's mountain cryosphere will have changed to an extent that will impact the landscape, the hydrological regimes, the water resources, and the infrastructure. The impacts will not remain confined to the mountain area but also affect the downstream lowlands, entailing a wide range of socioeconomical consequences. European mountains will have a completely different visual appearance, in which low- and mid-range-altitude glaciers will have disappeared and even large valley glaciers will have experienced significant retreat and mass loss. Due to increased air temperatures and related shifts from solid to liquid precipitation, seasonal snow lines will be found at much higher altitudes, and the snow season will be much shorter than today. These changes in snow and ice melt will cause a shift in the timing of discharge maxima, as well as a transition of runoff regimes from glacial to nival and from nival to pluvial. This will entail significant impacts on the seasonality of high-altitude water availability, with consequences for water storage and management in reservoirs for drinking water, irrigation, and hydropower production. Whereas an upward shift of the tree line and expansion of vegetation can be expected into current periglacial areas, the disappearance of permafrost at lower altitudes and its warming at higher elevations will likely result in mass movements and process chains beyond historical experience. Future cryospheric research has the responsibility not only to foster awareness of these expected changes and to develop targeted strategies to precisely quantify their magnitude and rate of occurrence but also to help in the development of approaches to adapt to these changes and to mitigate their consequences. Major joint efforts are required in the domain of cryospheric monitoring, which will require coordination in terms of data availability and quality. In particular, we recognize the quantification of high-altitude precipitation as a key source of uncertainty in projections of future changes. Improvements in numerical modeling and a better understanding of process chains affecting high-altitude mass movements are the two further fields that – in our view – future cryospheric research should focus on.

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The European mountain cryosphere: a review of its current state, trends, and future challenges

In the Austrian Alps the study of alpine permafrost started during the 1920ies and until about 1980 was mainly concentrated on rock glaciers. Since 1980 the number of publications related to permafrost increased and since the late 1990ies investigation of permafrost has been intensified. This introductory article provides an overview on the history of permafrost research in the Austrian Alps, on current activities including new results and a short outlook for the next years. Current research includes the distribution of rock glaciers and modelling of the distribution of permafrost in the Austrian Alps, the study of internal structures and the dynamics of active rock glaciers, permafrost monitoring, the response of permafrost to climate change and natural hazards related to permafrost. Core drilling on active rock glaciers including a detailed analysis of the frozen core and instrumentation of the bore holes for longterm monitoring of permafrost is one of the main issues for the future. In den österreichischen Alpen begann die Erforschung des alpinen Permafrostes in den 1920er Jahren und konzentrierte sich bis 1980 hauptsächlich auf Blockgletscher. Seit 1980 stieg die Anzahl der Publikationen über alpinen Permafrost und in den späten 1990er Jahren wurde die Forschungsaktivität intensiviert. Dieser einleitende Artikel bietet einen Überblick über die Geschichte der Permafrostforschung in den österreichischen Alpen, über gegenwärtige Forschungsaktivitäten und neue Ergebnisse sowie einen kurzen Ausblick auf geplante Aktivitäten für die nächsten Jahre. Gegenwärtige Forschungsarbeiten umfassen die Untersuchung der Verteilung der Blockgletscher und die Modellierung der Verbreitung des alpinen Permafrostes in den österreichischen Alpen, Untersuchung der internen Strukturen und Dynamik aktiver Blockgletscher, Permafrost-Monitoring, das Verhalten des Permafrostes in Hinblick auf Kimaänderungen sowie Naturgefahren in Zusammenhang mit alpinem Permafrost. Kernbohrungen auf aktiven Blockgletschern einschließlich einer detaillierten Analyse der gefrorenen Kerne und Instrumentierung der Bohrlöcher für ein langfristiges Permafrost-Monitoring zählen zu den wichtigsten Zielen für die nahe Zukunft. ____________________________________ _________________________________________________________________ _________________________________________________ ______________________________________________________ Permafrost Research in Austria: History and recent advances 1) 2)3) 3) 4) Karl KRAINER , Andreas KELLERER-PIRKLBAUER , Viktor KAUFMANN , Gerhard Karl LIEB , 5) 6)7) Lothar SCHROTT & Helmut HAUSMANN 1) Institute of Geology and Paleontology, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria; 2) Institute for Earth Sciences, University of Graz, Heinrichstrasse 26, 8010 Graz, Austria; 3) Institute of Remote Sensing and Photogrammetry, Graz University of Technology, Steyrergasse 30, 8010 Graz, Austria; 4) Institute of Geography and Regional Science, University of Graz, Heinrichstrasse 36, 8010 Graz, Austria; 5) Department of Geography and Geology, University of Salzburg, Hellbrunnerstraße 34, A-5020 Salzburg, Austria; 6) Central Institute for Meteorology and Geodynamics/ZAMG, Hohe Warte 38, A-1190 Vienna, Austria; 7) Institute of Geodesy and Geophysics, Vienna University of Technology, Vienna, Austria;

Permafrost research in Austria: History and Recent Advances

In the last century and a half, average summer temperatures have slowly been rising worldwide. The most observable consequence of this is the change in glacier sizes. For monitoring glacier area and volume, various measuring techniques exist—from measurements with a measuring tape and geodetic measurements to remote sensing and photogrammetry. A comparison of different measuring techniques on two Slovenian glaciers (the Triglav and Skuta glaciers) and two Austrian glaciers (the Gössnitzkees and Hornkees glaciers) is made. A long-term glacial retreat trend is presented for the Gössnitzkees, Hornkees, and Triglav glaciers because these glaciers can be monitored throughout the entire twentieth century by means of archival data. Despite their different sizes, the annual trend of glacial retreat was approximately the same in the period between 1929 and 2006.

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Measurements of small alpine glaciers: examples from Slovenia and Austria

Hinteres Langtalkar rock glacier (46°59‘N, 12°47‘E) is located in a glacially shaped cirque situated in the center of the Schober group of the Hohe Tauern range, Austria. This tongue-shaped creep phenomenon of mountain permafrost is approx. 850 m long, 200 to 350 m wide, and stretches vertically between 2455 m and 2725 m altitude. Over the course of time, the snout of the rock glacier has advanced into the uppermost cirque’s lip, which is much steeper than the cirque fl oor behind, causing disintegration of this part of the rock glacier through active sliding processes (since 1994). Consequently, fl ow velocities behind the frontal slope have signifi cantly increased because of a lack of counterpressure. Maximum horizontal fl ow velocities reached 2 to 2.5 m a -1 . The prevailing high longitudinal strain rates of up to 20x10-3 a -1 (2002-2006) have triggered surface ruptures and crevasse-like openings. In this paper we present quantitative information on the kinematics and surface deformation of the rock glacier based on the photogrammetric evaluation of multi-temporal aerial photographs (10 different epochs between 1954 and 2006) and annual geodetic measurements (1999-2007). Results obtained from recent investigations are highlighted. Based on the available information, covering a time span of 52 years, we analyze the changing kinematic state of Hinteres Langtalkar rock glacier. Special emphasis is put on the more recent situation of the rock glacier, which is characterized by the rapid development of tension cracks and the accelerated disintegration of the permafrost body. The main fi ndings of this paper are as follows: (1) There is most probably a persistent climatically-induced permafrost melt in the order of a few centimeters per year. (2) Specifi c topographic situations (e.g. increasing slope inclination) may cause acceleration of fl ow/creep of a rock glacier, with the implication of possible surface ruptures in case of high strain rates and insuffi cient internal cohesion. (3) Interannual changes of fl ow/creep velocities are most probably due to the thermal conditions of the permafrost body, more or less true irrespective of (2). Furthermore, the authors propose to augment the present monitoring program by a high-resolution airborne laser scanning (ALS) mission which should be repeated (at least once) at a time interval of several years depending on the height accuracy to be achieved and the prevailing permafrost melt.

Documentation and visualization of the morphodynamics of Hinteres Langtalkar rock glacier (Hohe Tauern range, Austrian Alps) based on aerial photographs (1954-2006) and geodetic measurements (1999-2007)

This publication presents the preliminary results of photogrammetr ic, geodetic and cartographic work carried out on the active Dosen rock glacier (Dosen Valley, Ankogel group, Hohe Tauern range of the Austrian Alps). Furthermore, an overview of former and also recent rock glacier measuring and mapping activities in Austria is given. Rock glaciers are perennially frozen debris masses which creep down mountain slopes. These creep phenomena of mountain permafrost have been studied intensively all over the world in the past few decades. As a result, long-term monitoring projects of rock glaciers have confirmed that changes of surface velocity and changes of volume, respectively, highly correspond to climatic change on earth. The outer Hochebenkar rock glacier has the longest continuous record of measurements and thus is the best observed rock glacier in Austria. Nevertheless, this rock glacier occupies a special position because of its quite large annual movements, which are mainly induced by the topographic conditions. The Dosen rock glacier was selected in order to widen the existing geodetic and photogrammetric observation program of active rock glaciers in Austria. As a first step a detailed geomorphometric study map at 1:5,000 scale covering the inner Dosen Valley was evaluated. Further cartographic work comprises a stereo-orthophoto map at 1:30,000 scale, two combined image-line maps at 1:10,000 scale, a detailed map of the Dosen rock glacier at 1:5,000 scale, and a thematic map at 1:5,000 scale indicating the velocity of flow of the Dosen rock glacier. The photogrammetrically determined flow vectors reveal that the mean annual horizontal velocity observed at the snout of the rock glacier has decreased from 22 cm/year (period from 1954 to 1975) to 13 cm/year (period from 1975 to 1993). Similar results were obtained in the Swiss Alps. During the whole observation period the Dosen rock glacier has advanced 6.6 meters in total. Precise geodetic measurements within an observation network (since 1995), and numerous terrestrial and aerial photographs (since 1994 and 1954, respectively) provide the basis for the first comprehensive geodetic deformation analysis of an active rock glacier in Austria. The investigations on the Dosen rock glacier were financially supported by the Austrian Science Foundation and by the Carinthian National Park Fund.

Geomorphometric monitoring of active rock glaciers in the austrian alps

The detection of an active rock glacier and the quantification of the observed surface movement as well as its temporal change using the D-InSAR method are presented. An average deformation rate of -7.7 mm/35 days in the radar line-of-sight, in the summer of 1992, was estimated. Whereas, the corresponding geodetic measurement, vertical component of 3D flow velocity, was about -8.0 mm/35 days. Additionally, the spatial distribution of the rock glacier surface deformation derived from the D-InSAR data matches the photogrammetric and geodetic generated results to a very high degree.

Viktor Kaufmann

Papers

Permafrost research in Austria: History and Recent Advances

Measurements of small alpine glaciers: examples from Slovenia and Austria

Documentation and visualization of the morphodynamics of Hinteres Langtalkar rock glacier (Hohe Tauern range, Austrian Alps) based on aerial photographs (1954-2006) and geodetic measurements (1999-2007)

Geomorphometric monitoring of active rock glaciers in the austrian alps

Estimation of alpine permafrost surface deformation using InSAR data