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A new methodology for shallow landslide forecasting in wildfire burned areas is proposed by estimating the annual probability of rainfall threshold exceedance. For this purpose, extensive geological fieldwork was carried out in 122 landslides, which have been periodically activated in Western Greece, after the devastating wildfires that occurred in August 2007 and burned large areas in several parts of Western Greece. In addition, daily rainfall data covering more than 40 years has been collected and statistically processed to estimate the exceedance probability of the rainfall threshold above which these landslides are activated. The objectives of this study are to quantify the magnitude and duration of rainfall above which landslides in burned areas are activated, as well as to introduce a novel methodology on rainfall-induced landslide forecasting. It has been concluded that rainfall-induced landslide annual exceedance probability in the burned areas is higher when cumulative rainfall duration ranges from 6 to 9 days with local differences due to the prevailing geological conditions and landscape characteristics. The proposed methodology can be used as a basis for landslide forecasting in wildfire-affected areas, especially when triggered by rainfall, and can be further developed as a tool for preliminary landslide hazard assessment.

The landslide is one of the most common geological hazards in nature, the rapid development of unmanned aerial vehicle (UAV) technology and virtual reality (VR) technology provides important data resources and technical support for immersive simulation and visual analysis of the landslide. Firstly, this paper focuses on the dynamic construction and exploratory analysis of VR scene in landslide hazard，then some key technologies such as diversified organization of landslide data， dynamic fusion visualization of VR scene are addressed in detail，thus a VR scene interaction method based on handle ray is proposed. Finally > a prototype system is implemented and a case study region is selected for experimental analysis. The experimental results show that the proposed method can dynamically construct landslide VR scene based on UAV remote sensing data，and can support the user to carry out immersive interaction and disaster information analysis. [ABSTRACT FROM AUTHOR]

In this report, we summarise the activities of the Research Institute for Geo-Hydrological Protection (IRPI, http://www.irpi.cnr.it/en/), of the Italian National Research Council (CNR, http://www.cnr.it/en/), as a World Centre of Excellence (WCoE) on Landslide Risk, of the International Programme on Landslides (IPL, http://iplhq.org). The report is organised as follows. After a brief description of CNR IRPI ("The Research Institute for Geo-Hydrological Protection"), we present recent developments related to landslide early warning systems ("Landslide early warning systems"), climate change and landslides interactions ("Landslides in a changing climate"), and landslide risk assessment, mitigation and dissemination efforts ("Landslide risk assessment, mitigation and dissemination efforts"). We conclude listing relevant papers published between 2017 and 2018 by CNR IRPI scientists ("References"). [ABSTRACT FROM AUTHOR]

A detailed characterization of outcrop fracture networks in the turbiditic flysch sequence of the Monte Venere Formation (Northern Apennines) together with in situ measurements of rock strength using the Schmidt hammer provided important insights into the sequence of deformation and the slope stability conditions. The inferred sequence of structure formation from oldest to youngest is bedding-parallel cleavage, veins and normal faults, joints, and strike-slip faults (sheared joints). Alteration halos around fractures (joints, splay joints, strike-slip faults, and some normal faults) point out that these structures were conductive to meteoric water during uplift and erosion in the Holocene. Calcite-filled veins without alteration halos are considered local barriers to fluid flow and diffusion. Bedding thickness controls rock fracturing characterization parameters in the Monte Venere Formation. Reactivation in shear of pre-existing structures, however, causes the formation of splay joint clusters that locally increase fracture density contributing to degrade the mechanical strength of the rock. These localized clusters are apparent in detailed outcrop maps but they are usually not detected by the rock fracturing characterization parameters. Our data also imply that the presence of bedding-parallel cleavage is more important than layer thickness in controlling the rock compressive strength and ultimately the peak shear strength along a potentially sliding surface. This study takes closer look at landslide formation in a sloped flysch sequence under Mediterranean climate conditions and allowed to consider a conceptual model for landslide occurrence in which structural discontinuities and meteoric water flow through fracture networks are main triggering factors. [ABSTRACT FROM AUTHOR]

With the continuous development of synthetic aperture radar technology, the application of SAR image data in landslide hazard information extraction has received attention and achieved some results. In this paper, the grayscale texture information features of SAR images after landslide disasters are combined with the expectation maximization algorithm to extract landslide information. The optimal threshold is calculated using the expectation maximization algorithm, and the image is divided into a landslide area and a non-landslide area.In this paper, the method is applied to Radarsat-2 SAR data in Yingxiu area after Wenchuan earthquake to obtain the distribution of landslide results. The method is also applied to other areas of the image for landslide extraction, and the correctness of the results is judged by comparing with the field measurement data and optical image analysis. Due to the particularity of the landslide, the method still needs further improvement in accuracy. The extraction results need further research in verification, so the method is not very good at present. Improvement needs further improvement. [ABSTRACT FROM AUTHOR]

This study focuses on one of the most complex petrographic and structural relief units in Romania, affected by significant earthquakes and uplift neotectonic movements, i.e. the Subcarpathian region. The Subcarpathians represent a highly fragmented hilly area subject to various mass movements and erosion processes, frequently affecting settlements, transport infrastructure and environmental values. The paper aims to present a landslide exposure assessment conducted for this region, following three main stages which are addressed in the context of present environmental conditions and their possible future changes: landslide susceptibility, landslide hazard and the exposure of elements at risk. It also intends to address and discuss the associated specific contexts, problems and challenges. By integrating selected landslide hazard scenarios, computed under different precipitation and seismic conditions, and key data on elements at risk (i.e. built-up areas, arable lands, permanent crops and major protected areas) into GIS spatial and statistical analyses, potential current and future landslide risk areas are outlined. Results are quantified at the Local Administrative Unit (LAU; towns and communes) level. The output maps reveal significant regional differences in landslide susceptibility and hazard according to the specific predisposing and triggering factors considered, as well as spatial variations in the landslide exposure in relation to specific land-uses and protected areas in the region. The present study contributes to increasing knowledge on landslide susceptibility, hazard, and exposure in the area and provides a ground for further related investigations. In addition, because of its predictive character, this study may constitute a useful tool for policy makers supporting decisions with regard to where future priorities should be focused. [ABSTRACT FROM AUTHOR]

This document describes technical concepts and terms related to landslide risk on slopes and hillsides, from a comprehensive approach. A general methodology is presented for the risk analysis and assessment according to the threat, given by the interrelation susceptibility - probability of landslide occurrence; and the vulnerability of the exposed elements, obtained from a multifactorial analysis that considers physical and social aspects. Susceptibility is obtained considering various conditioning and triggering factors of instability and the probability of event occurrence is estimated from deterministic methods. The vulnerability analysis is done considering the spatial and temporal components of the potential events, as well as the impact that these could have on the exposed elements, in terms of social and material losses. This methodology is applied to the study of an urban slope in the city of Tijuana, Mexico. [ABSTRACT FROM AUTHOR]

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Climate change can modify the frequency and intensity of extreme rainfall across the globe, leading to changes in hazards posed by rainfall-induced landslides. In Brazil, an example of a location with a high occurrence of landslides and with few studies on the subject is the municipality of Cunha, located in the State of São Paulo. In this way, the main aims of this study are twofold: 1) to identify and analyze areas susceptible to landslides and rainfall-induced landslide hazard in the municipality of Cunha; and 2) by using climate projections from the regional model Eta-HadGEM2-ES under RCP 4.5, to predict new extreme events and possible new landslides in this municipality, from 2024 to 2040. The susceptibility map has been prepared using selected physical-biotic environment elements whereas the hazard map has been produced using precipitation data. Using Eta-HadGEM2-ES climate projections under RCP 4.5, for precipitation events, results project the occurrence of 49 days with landslides for the period between 2024 and 2040. The outcomes of this study are considered of extreme relevance for the local community, public authorities, and decision-makers, to raise awareness regarding future urban planning strategies to prevent and mitigate the effects of catastrophes arising from natural hazard-induced disasters. • High susceptibility class represented 61.43% of the Cunha municipality. • The combination of daily and 5-day accumulate precipitation might trigger landslides. • 20.00% of Cunha municipality areas corresponds to very high landslide hazard. • 49 days with landslides could occur between 2024 and 2040 in Cunha municipality. [ABSTRACT FROM AUTHOR]

ABSTRAK Desa Tieng Kecamatan Kejajar secara umum memiliki kondisi topografi yang dapat menjadi faktor penyebab terjadinya tanah longsor seiring dengan perkembangan perkembangan aktivitas manusia. Untuk mengantisipasi dan mencegah terjadinya bencana alam tanah tanah longsor, maka perlu disediakan peta risiko tanah tanah longsor di Desa Tieng yang merupakan perpaduan antara peta bahaya dan peta kerentanan sebagai bahan pertimbangan yang penting dalam pencegahan dan penanggulangan tanah longsor. Penyusunan peta bahaya, kerentanan, dan risiko tanah longsor menggunakan ArcGIS dan ILWIS dengan menggunakan parameter hujan, lereng lahan, geologi, keberadaan sesar, kedalaman tanah, penggunaan lahan, infrastruktur, kepadatan pemukiman. Skoring dan pemberatan digunakan dalam penentuan peta bahaya dan kerentanan. Metode pengambilan sampel dalam penelitian menggunakan metode pengambilan sampel acak berstrata dengan berdasarkan zona bahaya tanah longsor di lokasi penelitian. Hasil penelitian ini menunjukkan bahwa zona tingkat bahaya tanah longsor terbagi menjadi 3 zona yaitu zona bahaya tinggi, sedang, dan rendah. Wilayah pemukiman berada pada zona bahaya tinggi dan sedang. Tingkat kerentanan total merupakan fungsi dari tingkat kerentanan fisik, sosial, dan ekonomi. Tingkat kerentanan fisik menggunakan faktor persentase kawasan terbangun, kepadatan bangunan, dan jenis material banguan. Tingkat kerentanan sosial menggunakan faktor kepadatan penduduk, persentase penduduk usia tua-balita, dan penduduk wanita. Tingkat kerentanan ekonomi menggunakan faktor persentase rumah tangga yang bekerja di sektor rentan, dan persentase rumah tangga miskin. Masyarakat Desa Tieng membuat sistem terassering untuk berkebun dan membuat bangunan penahan dari batu untuk mengurangi bahaya tanah longsor. Kesimpulan penelitian ini Desa Tieng berada pada risiko tanah longsor sedang dan tinggi. Penduduk yang berada pada zona risiko tinggi sebaiknya direlokasi terutama penduduk yang terletak berdekatan dengan tebing. ABSTRACT Tieng District Kejajar village generally has a topography which can be the causes of the landslides along with the development of human activity. To anticipate and prevent the occurrence of natural disasters landslides land, it is necessary to provide a map of landslide risk land in the village of Tieng which is a combination of hazard maps and vulnerability map as an important consideration in the prevention and mitigation of landslides. Preparation of hazard maps, vulnerability, and risk of landslides using ArcGIS and ILWIS using the parameters of rain, land slope, geology, the presence of faults, depths of soil, land use, infrastructure, residential density. Scoring and weighting are used in the determination of hazard and vulnerability maps. The sampling method in research using stratified random sampling method with a landslide hazard zones based on the location of the research. The results showed that the degree of landslide hazard zone is divided into three zones, namely the danger zone of high, medium, and low. Residential areas are in the danger zone of high and medium. Total vulnerability level is a function of the level of vulnerability of physical, social, and economic. The level of physical vulnerability using a percentage factor woke region, building density, and type of material banguan. The level of social vulnerability using a factor of population density, percentage of population age-old toddler, and the female population. The level of economic vulnerability using factors the percentage of households who work in vulnerable sectors, and the percentage of poor households. Tieng Village Community makes terassering system for gardening and create a barrier of stone buildings to reduce the danger of landslides. The conclusion of this study Tieng village are at risk of landslides medium and high. Residents who are at high risk zones should be relocated mainly residents located adjacent to the cliffs.

Many areas are exposed to different types of natural hazards including landslides, which can lead to loss of lives, injury to people, damage to property and disruption of economic activities. This paper assessed the landslide susceptibility and quantifies the hazard and risk related to landslides in Okeigbo, southwest, Nigeria using remote sensing imageries, geographic information system (GIS) and logistic regression model. The result revealed that slope, elevation, aspect, profile curvature, distance from road and land use influence landslide susceptibility. Current landslide and the most susceptible areas to landslides were within the areas with high slopes especially at slope angles of landslide occurred on slopes between 14 % and 25 % in the upper, steep and narrow ridge with elevation of between 413 m and 459 m. The landslide occurred northwest aspect class where there is increased land use activities characterized by deforestation and improper agricultural practices. It was further revealed that the landslide occurred about 200 m close to the road and potential areas were landslides can occur in the future are closely located within the 100-300 m buffer zones. Generally, Slopes have more influence than land cover for the susceptibility map. Although a smaller portion of the study area is presently located in the high hazard zone, intensive land use activities on the steep slope could expose the land to other triggering factors such as rainfall. A landslide susceptibility assessment and monitoring will assist in prediction, management future occurrences and general developmental planning in the area. Keywords: Landslide hazard, Vulnerability, Geographical information system; remotely sensed data