NH6.4

Specific features of current semiarid landscape along the Eastern Caucasus foothills (so-called Dagestan extra-mountain region) are badlands formed on loess and clay deposits. The active piping, erosional and gravitational processes present a direct hazard for extensive grazing activities and infrastructure facilities accommodated here. The badlands topography is complicated with the abundance of diverse pseudokarst forms such as blind valleys, caverns, different sized and shaped sinkholes. Such typical patterns as chains of elongated sinkholes, marking the direction of underground flow along the bottoms of erosional forms, are rather distinguishable on satellite imagery with submeter spatial resolution. However, the real density and morphometric analysis of surface pseudokarst forms can be well mapped and analyzed only by means of remote sensing data with ultrahigh spatial and vertical resolution (about several decimeters). For the area in study we used UAV-derived data from 100 m altitude of survey to produced Digital Terrain Model (DTM) with resolution of 20 cm. The automatic extraction of DTM’s for semiarid badland with sparse desert steppe vegetation was rather simple but there is obvious limitations of using UAV data for morphometric analysis of the badland were manifested in the formation of the so-called "dead zones" in case of the large and deep sinkholes. For a complete three-dimensional reconstruction of the badland topography, the terrestrial laser scanning data were additionally involved.

As a result of the analysis of the DTM with very high resolution, derived highly-detailed morphometric and hydrological models were built, reflecting the complex structure and genesis of the badland topography. Automatic identification and mapping of sinkholes reveal the prevalence of large sinkholes with a diameter of 5-15 m and a depth of 1-3 m along the erosional valleys for the study area. Along the slopes more smaller sinkholes forms (up to 0.3 m in diameter and up to 1 m in depth) were identified, the complex network of gullies and micro-terraces pattern were clearly reconstructed. Identification and mapping of sites with high susceptibility to current processes of different genesis was done: in particular, the identified closed catchment micro-basins are areas of predominance of piping processes, while the escarpments in the upper parts of the steep slopes of the badlands are most affected by erosional processes with formation of micro-gullies.

Under regular monitoring of piping, erosional and gravitational processes remodeling the badland topography, it is necessary to carry out multitemporal UAV surveys at low altitudes along with terrestrial laser scanning data. Such complex approach will make it possible to identify more reliably the current ratio of surface and groundwater runoff, and to early allocate and warn the hazardous geomorphological processes.

How to cite: Medvedev, A., Telnova, N., Alekseenko, N., Kudikov, A., Kuramagomedov, B., and Grozdov, Y.: The use of UAV-derived ultrahigh resolution data for the assessment of semiarid badland exposure to hazardous geomorphological processes: case of the Eastern Caucasus foothills, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9087, https://doi.org/10.5194/egusphere-egu22-9087, 2022.

How to cite: Frey, O., Werner, C., Manconi, A., and Coscione, R.: High-resolution mobile mapping of slope stability with car- and UAV-borne InSAR systems, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-8587, https://doi.org/10.5194/egusphere-egu22-8587, 2022.

Slope-related mass movements and erosional processes are common in all regions on Earth and especially dangerous in mountain areas, where they can rapidly transfer material, threatening human lives and infrastructure. However, the characteristics and activity of small scale (< 1000 m²) events in highly elevated tropical mountains remain poorly understood, even though these areas are often populated. The morphological characterization and investigation of the short-term dynamics of different types of mass movement and erosional processes can help infer about slope processes and take appropriate actions to limit associated hazards. This contribution aims:(1) To recognize the different processes that contribute to overall slope dynamics; (2) To document the morphology and short-term (annual dynamics) of geohazards-related landforms (e.g. small landslides, erosional rills and gullies); (3) To investigate the relationships between the characteristics and dynamics of geohazard sites and the landscape properties; (4) To develop a model of mass wasting mechanisms as agents of slopes development in tropical mountains.

The study areas were located in South America in Cordillera Vilcanota (Willkanuta) in Peruvian Andes and Eje Cafetero region in Colombian Andes. We documented and investigated the morphology and annual spatial pattern of activity of 15 sites representing different types of geohazards. Topographic analyses were based on time series of data captured using an unmanned aerial vehicle (UAV). Where possible, we investigated the observed dynamics of slope processes in combination with data on anthropogenic use to identify the main possible hazards. We identified four main types of processes responsible for transforming the land surface within studied sites: landslides, debris flows, falling, accelerated soil erosion. The morphological expression of these processes included the formation of erosional rills and gullies, landslide head scarps and lobes, debris flow channels, and avalanche deposits. In addition, we identified two main processes that control the activity of small geohazard sites. First, road works often caused activation of mass movements because of undercutting roadsides and associated anthropogenic earth movements. Second, the topographic properties of slopes (mainly slope and aspect) can increase the landscape response to direct anthropogenic pressure. Documented activity often follows a pattern of initiation of movements at the bottom of the site and its further propagation towards the upper escarpment. These results suggest that the dynamics of small geohazard sites strongly depend on local conditions and direct human impacts. While individual events are hard to predict, the presence of fine-scale rills and furrows might be helpful as indicators of probable increase in activity of slope processes. Over the longer time scales, that can be used to identify the most hazardous elements of the slope systems.

This project was funded by Narodowe Centrum Nauki (National Science Centre, Poland), grant number 2015/19/D/ST10/00251

How to cite: Ewertowski, M. and Tomczyk, A.: Mapping and geomorphological characterization of small-scale slope-related geohazards in the tropical high-mountain environment: case studies from Cordillera Villcanota, Peru and Eje Cafetero, Colombia, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-979, https://doi.org/10.5194/egusphere-egu22-979, 2022.

Mediterranean tectonically-active coastal areas are a highly-dynamic environment balancing internal tectonic dynamics with external geomorphic processes, as well as manmade influences. Especially in touristic areas characterized by high built-up pressure and land value, where these dynamics are even more concentrated, the evolution of coastal environments needs careful and high-resolution study to identify localized risk and the processes they derive from.
Recently, new advanced remote sensing techniques such as Unmanned Aerial Systems (UAS)- and Terrestrial Laser Scanners (TLS)-aided monitoring have improved our capabilities in understanding the natural processes and the geomorphic risks (i.e. mass movement phenomena).
An integrated study comprising Unmanned Aerial Vehicles (UAV) and Light Detection And Ranging (LIDAR) sensors was conducted in coastal areas of the southern Ionian Islands (Western Greece) aiming to the mitigation of earthquake-triggered landslide risk and to responsible coastal development. Located at the northwesternmost part of the Hellenic Arc, this area is characterized by high seismicity and has been affected by destructive earthquakes mainly due to the Cephalonia Transform Fault Zone (CTFZ), which constitutes one of the most seismic active structures in the Eastern Mediterranean region. One of the most common environmental effect triggered by these earthquakes are landslides distributed along fault scarps in developed and highly visited coastal areas. Furthermore, this area is highly susceptible to hydrometeorological hazards inducing intense geomorphic processes, including Medicanes among others.
These technologies allow a highly-detailed view of landslide processes, providing insights on the structures and factors controlling and triggering failures along coastal scarps as well as highlighting susceptible zones and high-risk areas with accuracy and mitigating adverse effects with precision and clarity. Overall, by providing a better understanding of the risks the approach used allows a more sustainable development of these coastal segments enhanced by risk mitigation.
The study was conducted in the framework of the project “Telemachus - Innovative Operational Seismic Risk Management System of the Ionian Islands”, co-financed by Greece and the European Union (European Regional Development Fund) in Priority Axis “Environmental Protection and Sustainable Development” of the Operational Programme “Ionian Islands 2014–2020”.

How to cite: Diakakis, M., Vassilakis, E., Mavroulis, S., Konsolaki, A., Kaviris, G., Kotsi, E., Kapetanidis, V., Sakkas, V., Alexopoulos, J. D., Lekkas, E., and Voulgaris, N.: An integrated UAS and TLS approach for monitoring coastal scarps and mass movement phenomena. The case of Ionian Islands., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7536, https://doi.org/10.5194/egusphere-egu22-7536, 2022.

Curvature Subcarpathians is one of Romania's most complex geological and geomorphic areas, frequently affected by landslides. The juxtaposition of snowmelt and spring rainfalls triggers significant damages to roads and buildings every few years (2018, 2021). In this context, accurately delineating the most affected areas becomes critical for evaluating landslides exposure. Aerial images have begun to be used more and more for different risk assessment phases to detect natural phenomena spread and damaged infrastructure elements. In this study, we use fully automatic detection of the landslide body and infrastructure elements (intact or collapsed buildings and roads) to support Regional Civil Protection Agencies in disaster intervention decision support. Our methodology is based on deep learning techniques for automatic detection, mapping and classification of landslide and infrastructure elements. A U-Net model was trained to detect the landslide body, and several Mask RCNN models were trained to detect the landslide features and infrastructure elements. The training accuracy for the U-Net model used for landslide body mapping is 0.86, and the validation accuracy is 0.80. The training accuracy of the Mask RCNN models is 0.76 for landslide cracks, 0.82 for roads and 0.92 for buildings. Some confusions between landslide cracks and local roads without asphalt are often seen in rural areas. The models are run on high-resolution aerial imagery collected with Unammend Aerial Vehicles after a landslide event. The data obtained from the deep learning models are further integrated with information from various sources such as aerial/satellite imagery, online GIS resources, weather forecasts, and spatial analysis techniques for providing a helpful tool to emergency management specialists. The tools have been integrated into a GIS platform that acts as a decision support system, and it can be used from a graphical user interface without the need to have programming skills.

Acknowledgement

This work was supported by a grant of the Romanian Ministry of Education and Research, CCCDI - UEFISCDI, project number PN-III-P2-2.1-PED-2019-5152, within PNCDI III (project coordinator Ionuț Șandric, https://slidemap.gmrsg.ro) and by the project PN19450103 / Core Program (project coordinator Viorel Ilinca).

How to cite: Chitu, Z., Sandric, I., Ilinca, V., and Irimia, R.: Mapping Exposure to Landslides by Means of Artificial Intelligence and UAV Aerial Imagery in the Curvature Subcarpathians, Romania, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-11334, https://doi.org/10.5194/egusphere-egu22-11334, 2022.

The dynamics that characterizes glaciers instabilities are often not well known because the study of these phenomena is done in many cases after their occurrence. A few examples of dedicated high resolution and high-frequency monitoring networks have been recently implemented to support risk assessment and management of glaciers affected by large potential instabilities.

The current climate trend and the rise of high mountain regions occupations by several anthropic activities have recently created areas affected by high potential risk due to the activation of glacial hazards, in particular during the summer season.

A few possible solutions are available: the substantial limitation of touristic exploitation of these areas or the management of the risk aimed to reduce the restrictions in accessing such high-value areas.

In this regard, it is required the implementation of high-resolution and high-frequency monitoring networks able to follow the evolution of the glacier and increase the knowledge of its dynamics.

In the Courmayeur municipality (Italy), the Planpincieux Glacier is a clear example of this critical condition: an active glacier with an unstable sector that could create a large ice avalanche that can reach the bottom of the valley, which is characterized by the presence of settlements and a famous touristic area.

For this reason, in the last decade, an innovative monitoring network has been implemented and tested in this very complex environment. The system comprises doppler radar, ground-based interferometric SAR and optical monitoring stations. The implementation of this hybrid network is a challenging task not only for the calibration of single instruments but also for the creation of network management that can acquire the dataset of different monitoring systems to obtain a precise representation of the evolution of the glacier. This is the final step that should be implemented for an effective strategy to support decision-makers.

How to cite: Giordan, D., Dematteis, N., Troilo, F., Perret, P., Gotterdelli, S., and Morandini, L.: Close-range hybrid solutions for glaciers instabilities monitoring, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-11192, https://doi.org/10.5194/egusphere-egu22-11192, 2022.

On September 19, 2017, Mexico was rocked by a 7.1 earthquake, causing an immense amount of damage in the states near the epicenter. This earthquake caused hundreds of damages in historical heritage, mainly in the states of Puebla, Oaxaca and Morelos. The patrimonial damages occurred were so extensive that they are prolonged till this day. Nepopualco Morelos was one of the towns that suffered great destruction by this shaking event. Their historical and main church, “Santiago the Apostle”, was  shattered in the shake, and the cleanup is still ongoing. The objective of this project was to create a 3D model of the Santiago the Apostle Church to view the process of restoration done by the National Institute of Anthropology and History (INAH). The 3D model obtained was the result of 478 images, which were captured by three different drone flights and a set of images shot on terrestrial. These flights were done by an Anafi Parrot drone, two circular flights and a double grid flight (180 and 256 images, respectively). For the purpose of obtaining a georeferenced accurate model, twelve ground control points were acquired in the field using a Emlid Reach RS+. The 3D model  presented in this project is a high-resolution model that allows the spatial analysis of the cabinet structure and represents a low-cost methodology. This model presents a centimeter resolution, while the error corresponds to 1.56%. The main contribution of this work is the obtainment of a 3D model of  Nepopualco´s historical church in which the final product shows the present stage of reconstruction done on the structural damages caused by the earthquake. The 3D reconstruction model will be delivered to the corresponding authorities of the National Institute of Anthropology and History. There is a possible consideration in creating other models that may help the INAH in the recovery process of cultural heritage affected by natural phenomena, as well as its structural mitigation. This project is the first effort on creating a digital catalog of these types of structures that make up Morelos’ historical heritage.
Acknowledgments:
Thanks to Arq. Antonio Mondragón from INAH,  Arq. Aimeé Mancilla and Arq.  Fabián Bernal Orozco for their facilities and support. We also want to thank Mr. Félix García Reyes and Gilberto García Peña, the community representatives, for their assistance in opening the entrance to the church.

How to cite: Méndez Serrano, J. E., Ruiz Sánchez, J. O., Ramírez Serrato, N. L., López Valdés, N., and Jácome Paz, M. P.: 3D Reconstruction of the ancient church Santiago the Apostle, Morelos, Mexico as a follow up to the damage caused by the 2017 earthquake, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-10813, https://doi.org/10.5194/egusphere-egu22-10813, 2022.

How to cite: Brennan, J., Burke, C., Ramsamy, L., Mitchell, H., and Kluza, K.: Using remote sensing and GIS to project climate risk for asset management users, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-5942, https://doi.org/10.5194/egusphere-egu22-5942, 2022.