Analysis of national and regional landslide inventories in Europe

A landslide inventory can be defined as a detailed register of the distribution and characteristics of past landslides in an area. Today most landslide inventories have the form of digital databases including landslide distribution maps and associated alphanumeric information for each landslide. While landslide inventories are of the utmost importance for land use planning and risk management through the generation of landslide zonation (susceptibility, hazard and risk) maps, landslide databases are thought to greatly differ from one country to another and often also within the same country. This hampers the generation of comparable, harmonised landslide zonation maps at national and continental scales, which is needed for policy and decision making at EU level as regarded for instance in the INSPIRE Directive and the Thematic Strategy for Soil Protection. In order to have a clear understanding of the landslide inventories available in Europe and their potential to produce landslide zonation maps as well as to draw recommendations to improve harmonisation and interoperability between landslide databases, we have surveyed 37 countries. In total, information has been collected and analysed for 24 national databases in 22 countries (Albania, Andorra, Austria, Bosnia and Herzegovina, Bulgaria, Czech Republic, Former Yugoslav Republic of Macedonia, France, Greece, Hungary, Iceland, Ireland, Italy, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and UK) and 22 regional databases in 10 countries. At the moment, over 633,000 landslides are recorded in national databases, representing on average less than 50% of the estimated landslides occurred in these countries. The sample of regional databases included over 103,000 landslides, with an estimated completeness substantially higher than that of national databases, as more attention can be paid for data collection over smaller regions. Yet, both for national and regional coverage, the data collection methods only occasionally included advanced technologies such as remote sensing. With regard to the inventory maps of most databases, the analysis illustrates the high variability of scales (between 1:10 000 and 1:1 M for national inventories, and from 1:10 000 to 1:25 000 for regional inventories), landslide classification systems and representation symbology. It also shows the difficulties to precisely locate landslides referred to in historical documents only. In addition, information on landslide magnitude, geometrical characteristics and age reported in national and regional databases greatly differs, even within the same database, as it strongly depends on the objectives of the database, the data collection methods used, the resources employed and the remaining landslide expression. In particular, landslide initiation and/or reactivation dates are generally estimated in less than 25% of records, thus making hazard and hence risk assessment difficult. In most databases, scarce information on landslide impact (damage and casualties) further hinders risk assessment at regional and national scales. Estimated landslide activity, which is very relevant to early warning and emergency management, is only included in half of the national databases and restricted to part of the landslides registered. Moreover, the availability of this information is not substantially higher in regional databases than in national ones. Most landslide databases further included information on geo-environmental characteristics at the landslide site, which is very important for modelling landslide zoning. Although a number of national and regional agencies provide free web-GIS visualisation services, the potential of existing landslide databases is often not fully exploited as, in many cases, access by the general public and external researchers is restricted. Additionally... (for full extended abstract please see attached document)JRC.H.7-Climate Risk Managemen

Part I - Landslide Inventory and Susceptibility and Hazard Zoning – Introduction

Landslide inventories and susceptibility and hazard maps are key tools for land use planning and management, civil protection plans, civil engineering works, and risk reduction programmes. Their importance helps understanding why approximately one sixth of all contributions to the Second World Landslide Forum were related to recent advances in these topics. This volume presents the state of the art on landslide inventory and susceptibility and hazard zoning. It contains experiences, methods and techniques applied in different physiographic, geological and climate settings of the world and for different types of landslides, from site-specific investigations to global scale analysis.JRC.H.7-Climate Risk Managemen

Identification of landslide hazard and risk ‘hotspots’ in Europe

Landslides are a serious problem for humans and infrastructure in many parts of Europe. Experts know to a certain degree which parts of the continent are most exposed to landslide hazard. Nevertheless, neither the geographical location of previous landslide events nor knowledge of locations with high landslide hazard necessarily point out the areas with highest landslide risk. In addition, landslides often occur unexpectedly and the decisions on where investments should be made to manage and mitigate future events are based on the need to demonstrate action and political will. The goal of this study was to undertake a uniform and objective analysis of landslide hazard and risk for Europe. Two independent models, an expert-based or heuristic and a statistical model (logistic regression), were developed to assess the landslide hazard. Both models are based on applying an appropriate combination of the parameters representing susceptibility factors (slope, lithology, soil moisture, vegetation cover and other- factors if available) and triggering factors (extreme precipitation and seismicity). The weights of different susceptibility and triggering factors are calibrated to the information available in landslide inventories and physical processes. The analysis is based on uniform gridded data for Europe with a pixel resolution of roughly 30 m 9 30 m. A validation of the two hazard models by organizations in Scotland, Italy, and Romania showed good agreement for shallow landslides and rockfalls, but the hazard models fail to cover areas with slow moving landslides. In general, the results from the two models agree well pointing out the same countries with the highest total and relative area exposed to landslides. Landslide risk was quantified by counting the number of exposed people and exposed kilometers of roads and railways in each country. This process was repeated for both models. The results show the highest relative exposure to landslides in small alpine countries such as Lichtenstein. In terms of total values on a national level, Italy scores highest in both the extent of exposed area and the number for exposed population. Again, results agree between the two models, but differences between the models are higher for the risk than for the hazard results. The analysis gives a good overview of the landslide hazard and risk hotspots in Europe and allows a simple ranking of areas where mitigation measures might be most effective.JRC.H.5-Land Resources Managemen

Recommendations for the quantitative analysis of landslide risk

This paper presents recommended methodologies for the quantitative analysis of landslide hazard, vulnerability and risk at different spatial scales (site-specific, local, regional and national), as well as for the verification and validation of the results. The methodologies described focus on the evaluation of the probabilities of occurrence of different landslide types with certain characteristics. Methods used to determine the spatial distribution of landslide intensity, the characterisation of the elements at risk, the assessment of the potential degree of damage and the quantification of the vulnerability of the elements at risk, and those used to perform the quantitative risk analysis are also described. The paper is intended for use by scientists and practising engineers, geologists and other landslide experts.JRC.H.5-Land Resources Managemen

The State of Soil in Europe : A contribution of the JRC to the European Environment Agency’s Environment State and Outlook Report— SOER 2010

This report presents a pan-European perspective on the state soil in Europe in light of available data held within the European Soil Data Centre (ESDAC) and the research activities within the Joint Research Centre’s Soil Action. Managed by the JRC on behalf of EU institutions, the ESDAC operates as a focal point for pan-European data and information on soil. The core of this report was prepared as the Soil Assessment (EEA, 2010f) of the ‘Environment — state and outlook 2010 Report’, generally referred to as the SOER 2010. Coordinated by the European Environment Agency, the SOER series is aimed primarily at policymakers, in Europe and beyond, involved with framing and implementing policies that could support environmental improvements in Europe. The information also helps European citizens to better understand, care for and improve Europe's environment. The soil assessment was one of a set of 13 Europe-wide thematic assessments of key environmental themes and the only one coordinated by the JRC. The initial contribution from the JRC to the SOER exercise has been updated with additional material that could not be included in the SOER due to space restrictions, together with supplementary information that was not available at the time of the publication of the original text. The report describes the knowledge and understanding of the state of soil in Europe and the main trends, outlook and policy responses for the key processes affecting soil resources in Europe. Unfortunately, our knowledge base on many of the key functions of soil that deliver vital environmental services and goods are still poorly developed. This aspect will be a key focus of the activities of the Soil Action for the next SOER, foreseen for 2015. A set of pertinent issues and facts from the assessment are presented in the Key Messages section that can be found at the start of this report. Much more information and data can be found that the web sites of the ESDAC (http://esdac.jrc.ec.europa.eu) or the JRC Soil Action (http://eusoils.jrc.ec.europa.eu). All SOER 2010 outputs are available on the SOER 2010 website: www.eea.europa.eu/soer.JRC.H.5-Land Resources Managemen

Guidelines for the selection of appropriate remote sensing technologies for landslide detection, monitoring and rapid mapping: the experience of the SafeLand European Project.

New earth observation satellites, innovative airborne platforms and sensors, high precision laser scanners, and enhanced ground-based geophysical investigation tools are a few examples of the increasing diversity of remote sensing technologies used in landslide analysis. The use of advanced sensors and analysis methods can help to significantly increase our understanding of potentially hazardous areas and helps to reduce associated risk. However, the choice of the optimal technology, analysis method and observation strategy requires careful considerations of the landslide process in the local and regional context, and the advantages and limitations of each technique. Guidelines for the selection of the most suitable remote sensing technologies according to different landslide types, displacement velocities, observational scales and risk management strategies have been proposed. The guidelines are meant to aid operational decision making, and include information such as spatial resolution and coverage, data and processing costs, and maturity of the method. The guidelines target scientists and end-users in charge of risk management, from the detection to the monitoring and the rapid mapping of landslides. They are illustrated by recent innovative methodologies developed for the creation and updating of landslide inventory maps, for the construction of landslide deformation maps and for the quantification of hazard. The guidelines were compiled with contributions from experts on landslide remote sensing from 13 European institutions coming from 8 different countries. This work is presented within the framework of the SafeLand project funded by the European Commission’s FP7 Programme.JRC.H.7-Climate Risk Managemen

Grondverschuivingen

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Landslide inventories in Europe and policy recommendations for their interoperability and harmonisation - A JRC contribution to the EU-FP7 SafeLand project

Landslides are a major natural hazard in most mountainous and hilly regions as well as in steep river banks and coastlines. In the EU Thematic Strategy for Soil Protection landslides are mainly recognized as a soil threat for which areas where they are likely to occur in the future have to be delineated, and measures to reduce their impact have to be designed. Thus the Strategy implies that landslide susceptibility, hazard and risk assessments are needed for appropriate risk management in Europe. To enable such assessments landslide databases, usually including landslide inventory maps and linked alphanumeric information, are a key infrastructure. They should contain information on the location of landslide phenomena, types, history, state of activity, magnitude or size, lithology involved, failure mechanisms, causal factors and the damage caused. Yet, it was not known which national (or regional) landslide databases contain all this information, and thus allow risk assessment. Therefore, this report makes a detailed review of national landslide databases in EU member states, EU official candidate and potential candidate countries and EFTA countries together with a number of regional databases, and proposes improvements for delineating areas at risk in agreement with the EU Soil Thematic Strategy and its associated Proposal for a Soil Framework Directive, and for achieving interoperability and harmonisation in agreement with INSPIRE Directive, which aims at establishing an Infrastructure for Spatial Information in the European Community. The report is based on the analysis of replies to a detailed questionnaire sent out to the competent persons and organisations in 37 European countries in spring 2010 and a review of literature, websites and main European legislation on the subject, carried out in the framework of the EU-FP7 SafeLand project. In total, information has been collected and analysed for 24 national databases in 22 countries and 22 regional databases in 10 countries. At the moment, over 633,000 landslides are recorded in national databases, representing on average less than 50% of the estimated landslides occurred in these countries. The sample of regional databases included over 103,000 landslides, with an estimated completeness substantially higher than that of national databases, as more attention can be paid for data collection over smaller regions. Both for national and regional coverage, information on landslide magnitude, geometrical characteristics, triggering factors, age and impact (damage and casualties) reported in national and regional databases greatly differs, as it strongly depends on the objectives of the database, the data collection methods used, the resources employed and the remaining landslide expression. In particular, information on landslide initiation and/or reactivation dates is generally included for less than 25% of records, thus making hazard and hence risk assessment difficult. In most databases, scarce information on landslide impact further hinders risk assessment at regional and national scales. About half of national and regional agencies provide free web-GIS visualisation services. Yet, the potential of existing landslide databases is often not fully exploited as, in many cases, access by the general public and external researchers is restricted. Additionally, the information is generally only available in the national or local language, thus hampering consultation for most foreigners. Based on these results, suggestions for a minimum set of attributes, i.e. those required for landslide risk assessments, to be collected and made available by European countries in support of EU policies are also presented.JRC.H.7-Climate Risk Managemen

Comparison of two landslide susceptibility assessments in the Champagne–Ardenne region (France)

The vineyards of the Montagne de Reims are mostly planted on steep south-oriented cuesta fronts receiving a maximum of sun radiation. Due to the location of the vineyards on steep hillslopes, the viticultural activity is threatened by slope failures. This study attempts to better understand the spatial patterns of landslide susceptibility in the Champagne–Ardenne region by comparing a heuristic (qualitative) and a statistical (quantitative) model in a 1120 km² study area. The heuristic landslide susceptibility model was adopted from the Bureau de Recherches Géologiques et Minières, the GEGEAA – Reims University and the Comité Interprofessionnel du Vin de Champagne. In this model, expert knowledge of the region was used to assign weights to all slope classes and lithologies present in the area, but the final susceptibility map was never evaluated with the location of mapped landslides. For the statistical landslide susceptibility assessment, logistic regression was applied to a dataset of 291 ‘old’ (Holocene) landslides. The robustness of the logistic regression model was evaluated and ROC curves were used for model calibration and validation. With regard to the variables assumed to be important environmental factors controlling landslides, the two models are in agreement. They both indicate that present and future landslides are mainly controlled by slope gradient and lithology. However, the comparison of the two landslide susceptibility maps through (1) an evaluation with the location of mapped ‘old’ landslides and through (2) a temporal validation with spatial data of ‘recent’ (1960–1999; n=48) and ‘very recent’ (2000–2008; n=46) landslides showed a better prediction capacity for the statistical model produced in this study compared to the heuristic model. In total, the statistically-derived landslide susceptibility map succeeded in correctly classifying 81.0% of the ‘old’ and 91.6% of the ‘recent’ and ‘very recent’ landslides. On the susceptibility map derived from the heuristic model, on the other hand, only 54.6% of the ‘old’ and 64.0% of the ‘recent’ and ‘very recent’ landslides were correctly classified as unstable. Hence, the landslide susceptibility map obtained from logistic regression is a better tool for regional landslide susceptibility analysis in the study area of the Montagne de Reims. The accurate classification of zones with very high and high susceptibility allows delineating zones where viticulturists should be informed and where implementation of precaution measures is needed to secure slope stability.status: publishe