Alpine Terrain Research Articles

The impact and sustainability of the prevention project 3! Winter Life Camp on young pupil’s knowledge on accident prevention and behaviour in winter alpine terrain

The impact and sustainability of the prevention project 3! Winter Life Camp on young pupil’s knowledge on accident prevention and behaviour in winter alpine terrain

Fine‐scale alpine plant community assembly: Relative roles of environmental sorting, dispersal processes and species interactions

Abstract Besides environmental sorting, other processes like biotic interactions and dispersal limitation are vital for the assembly of plant communities in high mountains and their re‐assembly under changing climatic conditions. Nevertheless, studies that compare the impact of these factors on plant community assembly above the tree line are largely lacking so far. We analysed occurrence changes in vascular plant communities of 492 permanent 1‐m2 plots in the alpine‐nival ecotone of Mt. Schrankogel, Austrian Alps by comparing resurvey data from 2014 with data from the initial survey in 1994. We combined these data with species inventories from 899 additional plots sampled in 2021 and 2022 across a larger landscape above the tree line covering an elevational range of 1700 m, which we used for fine‐scale habitat suitability modelling. We assessed the relative effects of projected habitat suitability, propagule pressure from surrounding populations and biomass density of neighbours on 1532 colonization and 372 extirpation events of 31 species observed on the permanent plots. We found that all three factors are significantly related to both colonisations and extirpations, with habitat suitability having the strongest, propagule pressure a slightly weaker, and vegetation density the weakest effect. Colonisations can be better explained by the three process proxies than extirpations. Our results indicate a crucial role of dispersal limitation besides the predominant effect of environmental filtering on the (re‐)assembly of the alpine‐nival plant community, while competitive/facilitative effects between plants tend to play a minor role. The strong imprint of nearby source plant populations on colonization/extirpation events suggests that recent plant migrations predominantly occur in small steps. This implies that while the topographically complex alpine terrain offers climatic microrefugia for plants, it may also pose potential barriers, hindering species from following their suitable climatic niches upwards. Synthesis: Besides filtering by environmental conditions dispersal limitation had a strong effect on the observed changes in a local alpine plant community over two decades. Limited dispersal capacities of plant species may counteract the ability of isolated cold areas to effectively shelter high alpine plants from the effects of climate warming.

A New and Robust Index for Water Body Extraction from Sentinel-2 Imagery

Land surface water is a key part in the global ecosystem balance and hydrological cycle. Remote sensing has become an effective tool for its spatio-temporal monitoring. However, remote sensing results exemplified in so-called water indices are subject to several limitations. This paper proposes a new and effective water index called the Sentinel Multi-Band Water Index (SMBWI) to extract water bodies in complex environments from Sentinel-2 satellite imagery. Individual tests explore the effectiveness of the SMBWI in eliminating interference of various special interfering cover features. The Iterative Self-Organizing Data Analysis Technique Algorithm (ISODATA) method and confusion matrix along with the derived accuracy evaluation indicators are used to provide a threshold reference when extracting water bodies and evaluate the accuracy of the water body extraction results, respectively. The SMBWI and eight other commonly used water indices are qualitatively and quantitatively compared through vision and accuracy evaluation indicators, respectively. Here, the SMBWI is proven to be the most effective at suppressing interference of buildings and their shadows, cultivated lands, vegetation, clouds and their shadows, alpine terrain with bare ground and glaciers when extracting water bodies. The overall accuracy in all tests was consistently greater than 96.5%. The SMBWI is proven to have a high ability to identify mixed pixels of water and non-water, with the lowest total error among nine water indices. Most notably, better results are obtained when extracting water bodies under interfering environments of cover features. Therefore, we propose that our novel and robust water index, the SMBWI, is ready to be used for mapping land surface water with high accuracy.

Innsbruck Summer School of alpine research—close range sensing techniques in alpine terrain

Innsbruck Summer School of alpine research—close range sensing techniques in alpine terrain

Sending pictures over radio systems of trail cam in border security and directing uavs to the right areas

In this study, a method is proposed for the trail cams to send data via narrow band communication systems in border security and counter-terrorism areas and to direct drones to the right areas. The success of UAVs lies in scanning the correct areas for observation or detection. UAVs should be fed with data to observe the correct regions, and the probability of detecting border security or terrorist elements should be increased. Instantaneous detection is performed by trail cam, which generally operate dependent on GSM. However, these devices cannot provide real-time data in border areas with low population density and no GSM service, particularly in counter-terrorism operations. In this study, the dependence of trail cam devices on GSM was eliminated, and data transfer over the radio system was established to enable real-time data flow in a wide field. After the trail cam device makes a detection, the data is sent via the APCO-25 JEMUS radio system with a capacity of 9.6 KB. The resolution of the detection image is reduced, allowing it to be displayed on a remote-control computer in less than one minute. As a result of the study, when an intelligent trail cam with object recognition capability is developed, the device can assess what the image might be in real-time. Obtaining real time detection data from trail cams in border areas and counter-terrorism zones without GSM infrastructure can expedite the direction of UAVs to the correct regions for intervention by military units. Additionally, confirming that trail cam detects via narrowband communication systems in locations where units are temporarily stationed and without alpine terrain minimizes the surveillance vulnerability of UAVs unable to perform imaging due to adverse weather conditions. This also establishes a warning system against potential attacks by terrorist elements.

The observed evolution of sub‐daily to multi‐day heavy precipitation in Switzerland

AbstractHeavy precipitation is a major natural hazard in the Alps. Understanding the possible changes due to climate change is a prerequisite for effective climate adaptation and protection. In this study, we revisit the long‐term (1901–2023) evolution of daily and multi‐day heavy precipitation intensity and frequency, discuss trends for sub‐daily to multi‐day events in the recent period 1981–2023 and investigate elevation dependencies in the complex topography of Switzerland. We analyze station measurements from MeteoSwiss' dense operational network covering the whole country and a wide range of elevation levels. We find that daily maximum precipitation and the frequency of precipitation events exceeding the 99th all‐day percentile have increased since 1901 with a peak in the 1980s and decreases thereafter. For the recent period 1981–2023, positive trends in summer heavy precipitation intensity are detected for short (10‐min to 3‐h) events, but no changes are found for the frequency of these moderate extreme events. For longer (1‐ to 5‐day) events on the other hand, decreases in intensity and frequency are found, especially for the winter half‐year. We hypothesize that the opposing trends on the centennial (1901–2023) vs. decadal (1981–2023) time scales are caused by the interaction between thermodynamics, reflecting the primary influence of human‐induced climate change, and the internal variability of atmospheric dynamics. Moreover, we observe a small negative elevation dependency of the daily long‐term trends up to 2300 m above sea level. For the 1981–2023 trends, no strong elevation dependencies are found for sub‐daily events. For daily events, we find small opposing negative summer and positive winter elevation dependencies for both intensities and frequencies. The reason for these tendencies remains unclear. Our results underscore the need to further investigate the interplay between climate change, internal variability of large‐scale dynamics and elevation to better understand heavy precipitation variability in the complex Alpine terrain.

Response of alpine ground temperatures to a rising atmospheric 0 °C isotherm in the period 1955–2021

Ground temperatures in alpine terrain vary considerably over short distances, particularly due to differences in elevation and incoming short-wave radiation but also snow and surface conditions. To allow for direct cross-site, interregional, and cross-disciplinary comparisons, we introduce a parameter called the potential 0 °C isotherm (PZDI) in the ground. This parameter represents an aspect- and elevation independent geo-projection of ground temperatures. It was calculated for several ground temperature datasets from the (sub-)permafrost zone in the European Alps. We analyse the reaction of the PZDI at different depths to long-term changes in atmospheric temperature, represented by the atmospheric 0 °C isotherm (AZDI). The close correspondence of PZDI and AZDI mainly provided two new insights: Based on 15 boreholes, the PZDI/AZDI interaction allowed a depth-dependent analysis of the magnitude and temporal evolution of the disequilibrium between atmosphere and ground and the potential heat transfer processes involved. Moreover, it allowed a reconstruction of the development of ground temperatures in the European Alps during the second half of the 20th century, adding 50 years to the longest existing time series measured in ice-poor permafrost. This extension into the past reveals a major warming at the end of the 1980s, which occurred before the start of the available permafrost temperature observations. In the 1955–2021 period, the 5-year running mean of the AZDI rose by 400 m, while the PZDI at 15 m depth rose by about 300 m. Projecting this warming into a permafrost distribution map shows a decline in shallow, ice-poor permafrost area by roughly 60 % since the 1980s. We expect the PZDI to follow the AZDI and to increase by another 100 m in the coming decade and up to at least 14 m depth. This would increase the area with loss of shallow permafrost to approximately 80 % since the 1980s.

Another Case of Making Choices: Alpine terrain, large-scale sites and mass finds of the 20th century

As in many other European countries, Austria's archaeologists have been dealing with the remains from two World Wars as part of excavations for years. Over the last 20 years, three topics have become very important in Austrian Heritage Management and the following contribution attempts to give an overview. The three big issues are: There are still an unknown number of camps from both World War II and World War I Alpine terrain holds the remains of two World Wars on slopes and ridges of up to 3000m above sea level. These sites present challenges in terms of climate change, tourism and public interest in an area of conflict. Industrially produced mass finds of the 20th century from excavations can be connected with atrocities from the two wars and are therefore worthy of protection. Who decides, and on what basis?

Flying towards the Future: Using Drones to Detect Lizards in Remote Alpine Terrain

Climate change is exerting significant impacts on ecosystems worldwide, with alpine regions being particularly vulnerable. Alpine fauna is relatively poorly understood, particularly in terrain which is difficult for humans to survey. Knowledge of alpine species is further limited by a paucity of survey techniques that are widely applicable in this environment. Drones have potential as a low-impact tool for surveying fauna in remote alpine terrain. New Zealand’s diverse alpine lizards are an ideal system for exploring novel survey techniques. We build on previous research demonstrating the potential of drones for surveying alpine lizards by evaluating (1) how closely a drone can approach different alpine lizard species in scree, talus, and tussock-grassland habitats and (2) the effectiveness of drone surveys compared to traditional systematic visual searches for these species and habitats. The drone (model: DJI Mavic Air 2) was able to approach within 0.1–2.5 m of a lizard (mean = 0.77 m) before triggering a flight response. Systematic visual searches outperformed drone surveys in all habitats accessible to human observers. However, drones were relatively effective in talus habitats, demonstrating their potential utility in inaccessible rocky alpine habitats. Improvements to drone technology may further enhance the utility of drone-based surveys in ecological research.

Event-based soil erosion and sediment yield modelling for calculating long-term reservoir sedimentation in the Alps

ABSTRACT Among the most characteristic offsite effects of soil erosion, reservoir sedimentation is one of the longlasting problems pertaining to storage capacity and dam operations. In this work, sedimentation rates of the Fortezza reservoir in South Tyrol (Italian Alps) are analysed for nine erosive events over 14 months. Sediment rates are calculated through a modified Universal Soil Loss Equation (USLE) combined with a Sediment Delivery Ratio (SDR) module at 2.5 m resolution. The topographic factor is adjusted to the Alpine terrain, and an additional factor is included to consider the nonerodible parts of the basin. The results are validated against a 14-month sediment yield obtained by high-resolution (0.2 m) reservoir bathymetric analyses. The calculated sediment yield has an absolute deviation of 4.8% from the measured one. The results indicate that these methods can be successfully applied for the estimation of reservoir sedimentation rates in the Alps.

Innsbruck Summer School of Alpine Research—Close‐Range Sensing Techniques in Alpine Terrain

Innsbruck Summer School of Alpine Research—Close‐Range Sensing Techniques in Alpine Terrain

Radiocarbon signatures of carbon phases exported by Swiss rivers in the Anthropocene.

Lateral carbon transport through the land-to-ocean-aquatic-continuum (LOAC) represents akey component of the global carbon cycle. This LOAC involves complex processes, many of which are prone to anthropogenic perturbation, yet the influence of natural and human-induced drivers remains poorly constrained. This study examines the radiocarbon (14C) signatures of particulate and dissolved organic carbon (POC, DOC) and dissolved inorganic carbon (DIC) transported by Swiss rivers to assess controls onsources and cycling of carbon within their watersheds. Twenty-one rivers were selected and sampled during high-flow conditions in summer 2021, a year of exceptionally high rainfall. Δ14C values of POC range from -446‰ to -158‰, while corresponding ranges of Δ14C values for DOC and DIC are -377‰ to -43‰ and -301‰ to -40‰, respectively, indicating the prevalence of pre-aged carbon. Region-specific agricultural practices seem to have an influential effect on all three carbon phases in rivers draining the Swiss Plateau. Based on Multivariate Regression Analysis, mean basin elevation correlated negatively with Δ14C values of all three carbon phases. These contrasts between alpine terrain and the lowlands reflect the importance of overriding ecoregional controls on riverine carbon dynamics within Switzerland, despite high spatial variability in catchment properties. This article is part of the Theo Murphy meeting issue 'Radiocarbon in the Anthropocene'.

Accuracy and consistency of space-based vegetation height maps for forest dynamics in alpine terrain

Monitoring and understanding forest dynamics is essential for environmental conservation and management. This is why the Swiss National Forest Inventory (NFI) provides countrywide vegetation height maps at a spatial resolution of 0.5 m. Its long update time of 6 years, however, limits the temporal analysis of forest dynamics. This can be improved by using spaceborne remote sensing and deep learning to generate large-scale vegetation height maps in a cost-effective way. In this paper, we present an in-depth analysis of these methods for operational application in Switzerland. We generate annual, countrywide vegetation height maps at a 10-m ground sampling distance for the years 2017–2020 based on Sentinel-2 satellite imagery. In comparison to previous works, we conduct a large-scale and detailed stratified analysis against a precise Airborne Laser Scanning reference dataset. This stratified analysis reveals a close relationship between the model accuracy and the topology, especially slope and aspect. We assess the potential of deep learning-derived height maps for change detection and find that these maps can indicate changes as small as 250 m2. Larger-scale changes caused by a winter storm are detected with an F1-score of 0.77. Our results demonstrate that vegetation height maps computed from satellite imagery with deep learning are a valuable, complementary, cost-effective source of evidence to increase the temporal resolution for national forest assessments.

Glacier, permafrost and thermokarst interactions in Alpine terrain: Insights from seven decades of reconstructed dynamics of the Chauvet glacial and periglacial system (Southern French Alps)

AbstractThis study analyses the long‐term dynamics in the Chauvet glacial and periglacial system (southern French Alps) over seven decades (1948–2020), where several lake outburst floods have been documented since 1930. To accurately describe and explain the complex dynamics of this site, our multidisciplinary approach combines (1) photogrammetry of historical aerial photographs and modern high‐resolution satellite and UAV images, (2) geophysical surveys and (3) geomorphological mapping. We provide evidence for spatial and functional interactions between glacial and periglacial features, especially in the lower sector where different landforms with variable ice‐ and debris‐content and specific dynamics are interplayed. We found the highest thinning rates on ice‐rich terrain located in the central part of the valley bottom, which, together with bedrock morphology, most probably determine the location of the thermokarst. We also documented an overall acceleration of the creeping of the landforms after the 2000s, with a flow direction largely oriented towards the thermokarst depression. The outburst water flowed through a conduit whose successive opening and closure seem to mainly depend on the rate of lateral convergence of left‐ and right‐hand landforms and on the rate of ice melting (and roof collapse) along the conduit walls. Today, the site of Chauvet still represents a potential hazard for the region due to the large water storage capacity (up to 180 000 ± 450 m3) and the development of a predominantly bucket shape in the thermokarst sector.

Slight carbon-isotope perturbation at the J/K boundary (base of the Calpionella Zone) – A proxy tool for correlation? A brief summary

Stable isotope (δ13C, δ18O) data from bulk rock in the Jurassic–Cretaceous transition are characterised by stability of values in many Tethyan carbonate sections, predominantly those laid down under deeper-water marine conditions. The generally straight trend in the δ13Ccarb curve at the J/K boundary interval does not show any significant value expressions that are useful for interregional correlation. However, in several bio- and magnetostratigraphically well-calibrated sections that have been studied, especially in the Carpathian–Alpine terrain (and some additional sections elsewhere in Tethys), a very slight carbon isotopic negative excursion directly at the J/K boundary (sensu base of the Calpionella Zone/Alpina Subzone) shows an almost identical trend. We assume it represents a rather weak geochemical marker at the Tithonian/Berriasian boundary which, nevertheless, may be identified as a useful tool for stratigraphic correlation.

Methodology and Results of Staged UAS Photogrammetric Rockslide Monitoring in the Alpine Terrain in High Tatras, Slovakia, after the Hydrological Event in 2022

There are numerous talus cones that have formed by long-term geological processes and sudden hydrological events in the Small Cold Valley (High Tatras National Park in Slovakia). Frequent hiking trails lead here; therefore, their safeness needs to be monitored due to recent rock avalanches and landslides. A complex methodology for monitoring changes in talus cones was developed to determine the extent, pace, nature, and origin of the morphological changes in the land in this complex high-mountain terrain. Non-contact UAS photogrammetry with SfM-MVS processing was applied as a quick, reliable, and environment-friendly data acquisition method. For proper georeferencing, a network of GCPs and stabilized surveying points were established by terrestrial geodetic surveying. Together with an evaluation of the methodology, the results comparing the actual state of a talus cone in 2018 and 2022 (after the significant hydrological event) are presented. Comparing and analyzing spatial models represented by point clouds, with an accuracy of centimeter level, was obtained. The detected morphological changes reached values in meters. A differential model expresses the distribution of the morphological changes. In conclusion, geodetic and geological knowledge is synthesized to evaluate the phenomena occurring in this territory.

Estimating true density in large, alpine herbivores using Google Earth imagery

Density is a fundamental ecological parameter that is often difficult to estimate in large herbivores due to the wide spatial extent of their populations and imperfect detectability of individuals. We searched Google Earth imagery using an independent double‐observer protocol to estimate elk Cervus elaphus density in Yellowstone National Park, WY, USA, on summer range that had never been systematically surveyed. Detectability of elk was high at 0.836 (95% CRI: 0.769, 0.909) producing high precision in our density estimates. Elk density estimates ranged from a minimum of 8.9 elk km−2 over a 214.8 km2 search area (95% CRI: 7.9, 10.9) to a maximum of 14.0 elk km−2 over 98.5 km2 of nonforested, alpine terrain (95% CRI: 13.5, 14.9). These estimates of elk density are comparable to the highest elk densities ever recorded in Yellowstone which primarily derive from winter, at low elevations, prior to wolf Canis lupus reintroduction. A log‐linear positive effect of open landcover on density suggested preference for open terrain. Multiple survey designs may be possible with satellite imagery that would allow further refinement of noninvasive abundance estimation over large scales.

Relating storm-snow avalanche instabilities to data collected from the Differential Emissivity Imaging Disdrometer (DEID)

Storm-snow avalanches are challenging to forecast due to complex alpine terrain and during rapidly changing weather conditions. They can result in loss of lives and significant economic impact. We describe how a new device that continuously measures with high-frequency snowflake mass, size, density, and type, the Differential Emissivity Imaging Disdrometer (DEID), and show how the DEID can be used to aid avalanche forecasting when coupled with a storm-snow stability model. DEID measurements of snow accumulation, snow water equivalent (SWE), and snow density obtained during seventeen storms taken at the mid-Collins Snow-Study Plot at Alta Ski Area in Utah's Central Wasatch mountain range during winter 2020–2021 show excellent agreement with infrequent manual measurements. Additionally, two new variables, the Shape Density Index (SDI) and Complexity, are proposed and used to classify snowflake habit and estimate storm-snow shear strength. We illustrate how these DEID-derived data can be used to identify layers of concern in the storm snow such as density inversions, in real-time without digging snow pits. Furthermore, the DEID-data are used to run four variations of the SNOw Slope Stability model (SNOSS) for the storms investigated. The results are evaluated with data collected from tilt-board tests, infrasound measurements, and visual observations of avalanches. For a total fourteen storms analyzed, the DEID-driven SNOSS-modeled minimum stability index predicts the general stability of the storm-snow as indicated by observed avalanches, both natural and of unknown cause. The results provide a promising approach for nowcasting instabilities within storm-snow layers with a single instrument.

Erratum: Accuracy of UAV photogrammetry in glacial and periglacial alpine terrain: A comparison with airborne and terrestrial datasets

An erratum on:Groos AR, Aeschbacher R, Fischer M, Kohler N, Mayer C and Senn-Rist A (2022) Accuracy of UAVPhotogrammetry in Glacial and Periglacial Alpine Terrain: A Comparison With Airborne and TerrestrialDatasets. Front. Remote Sens. 3:871994. doi: 10.3389/frsen.2022.871994An omission to the funding section of the original article was made in error. Thefollowing sentence has been added: "Open access funding was provided by theUniversity Of Bern".The original version of this article has been updated.

Dam construction in alpine terrain to withstand natural hazards

Dam construction in alpine terrain to withstand natural hazards