This year, we will also participate in the 10th International Conference of the International Association of Geomorphologists (IAG). Two of our contributions in the frame of PROSLIDE were accepted in the format of a 15-min oral presentation and a poster entitled as follows:

Applying a hierarchical Generalized Additive Model to integrate predisposing, preparatory and triggering factors for landslide prediction (session ICG2022-19 – Geomorphological hazards and risk management)  scheduled for Monday, Sep 12th at 18:00 (GMT+1). Please find the abstract here.

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Comparing different strategies to incorporate the effectively surveyed area into landslide susceptibility modeling (session ICG2022-19 – Geomorphological hazards and risk management) scheduled for Tuesday, Sep 13th at 16:45 (GMT+1). Please find the abstract here.

Find out more details at the meeting programme CO Meeting Organizer ICG2022 (copernicus.org)

This year, we are happy to participate in the European Geosciences Union (EGU) General Assembly 2022. We were accepted for two PROSLIDE contributions in the format of 7-min short oral presentations entitled as follows:

A data-driven approach to establish prediction surfaces for rainfall-induced shallow landslides in South Tyrol, Italy (session NH3.7 – Towards reliable landslide early warning systems)  scheduled for Wednesday, May 25th at 14:25 CEST. Please find the abstract here.

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Space-time modeling of rainfall-induced shallow landslides in South Tyrol, Italy (session NH3.6 – Space and time forecasting of landslides) scheduled for Tuesday, May 24th at 13:27 CEST. Please find the abstract here.

For more details about the conference program visit CO Meeting Organizer EGU22 (copernicus.org).

On December the 10^th, Lotte de Vugt presented her thesis concept and her work on the PROSLIDE project as part of an application colloquium to the Innsbruck Doctoral College (IDC) Natural Hazards in Mountain Regions. The presentation was titled “Improving physically-based shallow landslide modelling – a case study in the Passeier valley, South Tyrol” and discussed the first results from the fieldwork, inventory mapping and the first model runs of the physically-based assessment in the Passeier valley.

The IDC Natural Hazards in Mountain Regions provides an interdisciplinary environment for PhD students from Innsbruck to further develop their academic and soft skills.

https://www.uibk.ac.at/en/alpinerraum/idcs/dp-mountainhazards/

Last Friday, November 5th,  Stefan Steger presented analyses related to the PROSLIDE project to the international landslide research community at the World Landslide Forum 5 WLF5 | World Lanslide Forum 5 (iplhq.org). He presented A statistical exploratory analysis of inventoried movements for South Tyrol (Italy) as part of  the Theme 2: Hazard and vulnerability mapping and zonation.

Screenshot of the presentation.

The past Friday, October 8th, fieldwork activities were carried out in the Passeier Valley. Like in the previous two field trips (First field trip – June 17th and Field trip campaign July 26th – 30th), the primary goals were to take soil samples and execute the DCPT (Dynamic Cone Penetration Test) to determine hydrological and geotechnical soil properties. This time there was no need for digging a soil pit, as the soil samples could be taken from a large old landslide scarp. According to the owner of the field, this landslide occurred due to an earthquake around 2000.  However, by checking the USGS database of past earthquakes, it was found that the landslide likely correlates to a relatively large earthquake that occurred on July 17^th of 2001, with a magnitude of 4.7 and its epicenter in the middle of the Passeier Valley (https://www.volcanodiscovery.com/earthquakes/quake-info/4826702/mag4quake-Jul-17-2001-northern-Italy.html)

On October 20^th, Lotte de Vugt presented her work on the construction of a more detailed landslide inventory of the August 5^th 2016 storm event in the Passeier valley during the Disaster Research Day Seminars of the DNCA (Disaster Competence Network Austria). The title of the presentation was: “Compilation of event-based shallow landslide inventories based on high-resolution earth observation imagery – a test case in the Passeier valley (South Tyrol, Italy)”.

The figure below shows how the more detailed landslide inventory constructed with Planetscope and RapidEye imagery compares to the national italian inventory (IFFI). The abstract of the presentation can be found here, in the linked “Konferenzband”: https://www.dcna.at/index.php/de/drd21-de.html

Figure: Comparison of the landslide locations in the IFFI database and manually mapped landslides on PlanetScope imagery, for a storm event that occurred on the 5th August, 2016. PlanetScope imagery (3 m resolution) taken on 2016-08-24 (Planet Team, 2016).

On September 17th, Stefan Steger from Eurac Research participated in the Civil Protect 2021 event to present Proslide activities to the public and local decision makers. The session was entitled Online inventory of mass movements (fierabolzano.it). His presentation was entitled Analisi dei movimenti di massa in Provincia di Bolzano and it was presented during the session Inventario on-line dei movimenti di massa: quali sono i vantaggi per questa amministrazione?

Screenshot of the program event.

During the week of July 26^th  – 30^th, fieldwork in the Passeier Valley was conducted with the main goal of data collection. The collected information corresponds to soil samples and the execution of the Dynamic Cone Penetration Test (DCPT). Laboratory analysis will be carried out from the collected data to classify the soil material and extract hydrological and geotechnical parameters such as soil density, water content, hydraulic conductivity, cohesion, and friction angle, which are essential inputs for the physically-based modeling.

The fieldwork in the five days was mainly divided into two stages. The first one consisted of digging a soil pit (with dimensions of 1m x 1m x 1m) at each previously selected location to have a clean soil profile for descriptions and sampling. Out of the soil profile, two buckets of material and several ring-shaped samples for laboratory analysis were taken at different depths to have a suitable representation of the soil profile. Furthermore, the second stage involved the execution of the DCPT to determine the soil depth and have a general overview of the soil structure. All the sampling and tests were done after discussing and getting permission from the landowners.

Lastly, the fieldwork team was very grateful for the friendliness of the farmers in the Passeier valley. The conversations with them gave great detail of information on the local problems with landslides and of course, their corporation in allowing the samples to be taken from their fields, was also very thankful.

On the 13^th of July Eurac Research met with the Consiglio Nazionale delle Ricerche – Istituto di ricerca per la protezione idrogeologica (CNR IRPI). This is the research institute for geo-hydrological protection. Some of the most well-known researchers in the field of rainfall thresholds work in the latter organization. CNR IRPI was represented by Stefano Luigi Gariano, Maria Teresa Brunetti, Massimo Melillo and Silvia Peruccacci. On the Eurac side Stefan Steger, Alice Crespi, and Robin Kohrs participated. As an external researcher from the University of Jena, Jason Goetz also attended the meeting. The goal of the meeting was to present the current status of the rainfall thresholds that are developed within the Proslide Project. In addition, a mutual exchange on recent developments and recurring challenges turned out to be very beneficial. Finally, another meeting with the final results was proposed.

First, Eurac presented his work on the thresholds for South Tyrol and in doing so highlighted the issues he faced. These include common questions as the generalization vs the precision for thresholds or the frequent topic of rainfall event definition. After the presentation, the round was open for discussion and questions. With ongoing time, it became more and more evident that the input data for the threshold, and its quality, is crucially important. Not only the temporal and spatial resolution of the rainfall data or the accuracy of the landslide data are decisive for the successful development of rainfall thresholds. Rather a separation between a dedicated landslide catalog and a landslide database should be made. While the former one usually contains dedicated research on each single entry that fits the research needs, the latter one normally contains many movements of potentially different types. It then depends on the researcher to filter out those, that are of interest and fit the research questions. Furthermore, differences in the approaches to develop rainfall thresholds were reviewed. As anticipated beforehand, there is not one single best approach. Instead, there are many different methods that each have their legitimation and should be carefully examined and discussed.

The presented results were a status quo at that time. Hence, another meeting with the final results was planned for the end of this research line of the project. Also, CNR IRPI kindly provided us with an extract of their landslide catalog for the area of South Tyrol. This data is and will be used to validate models that are built using data from the IFFI database

Screenshot from the meeting

On June 17^th, fieldwork activities were carried out in the Passeier valley. The field trip had several goals. The main one was to get familiar with the study area chosen for the physically-based approach of the landslide hazard assessment. Besides, getting the first soil samples to determine the hydrological and geotechnical parameters of the soil and testing out the equipment that will be used during the next field campaigns at the end of July.

The first stop was a meadow near Sankt Martin in Passeier on the south-facing hillside. After a very informative conversation with the landowner about previous landslides in the area, a Dynamic Cone Penetration Test (DCPT) was executed. The information from the DCPT can be used to determine the regolith depth, one of the most important parameters in the physically-based model. At one of the three test sites for the DCPT, a soil pit was dug to assess the soil structure and take soil samples from several depths.

The second stop was on the north-facing hillside, between Quellenhof and Neuhaus. A Terrestrial Laser Scanning (TLS) acquisition was performed. This acquisition will be used to construct a Digital Elevation Model (DEM) with a high resolution. This DEM can be used to find signs of previous landslide occurrences among all its potential uses. It is known that several landslides occurred at the site in 2016; nevertheless, since the latest DEM is from 2014, this cannot be used for the 2016 event. Therefore, the DEM generated from the TLS will cover this gap.