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Abstract. Many shallow landslides and debris flows are precipitation initiated. Therefore, regional landslide hazard assessment is often based on empirically derived precipitation intensity-duration (ID) thresholds and landslide inventories. Generally, two features of precipitation events are plotted and labeled with (shallow) landslide occurrence or non-occurrence. Hereafter, a separation line or zone is drawn, mostly in logarithmic space. The practical background of ID is that often only meteorological information is available when analyzing (non-)occurrence of shallow landslides and, at the same time, it could be that precipitation information is a good proxy for both meteorological trigger and hydrological cause. Although applied in many case studies, this approach suffers from many false positives as well as limited physical process understanding. Some first steps towards a more hydrologically based approach have been proposed in the past, but these efforts received limited follow-up. Therefore, the objective of our paper is to (a) critically analyze the concept of precipitation ID thresholds for shallow landslides and debris flows from a hydro-meteorological point of view and (b) propose a trigger–cause conceptual framework for lumped regional hydro-meteorological hazard assessment based on published examples and associated discussion. We discuss the ID thresholds in relation to return periods of precipitation, soil physics, and slope and catchment water balance. With this paper, we aim to contribute to the development of a stronger conceptual model for regional landslide hazard assessment based on physical process understanding and empirical data.

Abstract. To manage natural risks, an increasing effort is being put in the development of early warning systems (EWS), namely, approaches facing catastrophic phenomena by timely forecasting and alarm spreading throughout exposed population. Research efforts aimed at the development and implementation of effective EWS should especially concern the definition and calibration of the interpretative model. This paper analyses the main features characterizing predictive models working in EWS by discussing their aims and their features in terms of model accuracy, evolutionary stage of the phenomenon at which the prediction is carried out and model architecture. Original classification criteria based on these features are developed throughout the paper and shown in their practical implementation through examples of flow-like landslides and earth flows, both of which are characterized by rapid evolution and quite representative of many applications of EWS.

Este artigo relata a tentativa de decolonizar a pesquisa de campo, enfrentando o desafio de avaliar criticamente as disciplinas de Geografia ministradas na Turma Alto Rio Negro do Curso de Licenciatura Formação de Professores Indígenas da Faculdade de Educação da Universidade Federal do Amazonas (FPI/FACED/UFAM). Inspirados nas perspectivas da etnografia decolonial propostas por Olivera (2014) e Carvalho (2001) decidimos buscar parâmetros avaliativos dialogando com os egressos do curso, hoje professores graduados no município de São Gabriel da Cachoeira/AM, reconhecendo nossa posição como pesquisadores em encontro e aprendizagem com os professores indígenas. A partir desses diálogos, elaboramos, conjuntamente, os parâmetros para avaliação que apresentamos nesse artigo.

O artigo objetiva discutir o uso do discurso como elemento de mediação no processo de desenvolvimento do raciocínio geográfico. Como dimensão que constitui parcialmente as relações sociais e práticas materiais, torna-se um campo fértil de investigação nas aulas de geografia na escola, que pode ser auxiliar tanto no desenvolvimento do pensar geográfico quanto dos objetos e fenômenos de interesse da Geografia Escolar. Para tanto, buscou-se discutir suas possibilidades a partir da filosofia da linguagem do Círculo de Mikhail Bakhtin e da Análise de Discurso Crítica. Ao final, apresenta-se uma análise em caráter de ilustração e aprofundamento, a partir de uma canção, com vistas a elucidar as perspectivas adotadas em torno de um problema social.

Intro -- Dedication -- Foreword -- Preface -- Acknowledgements -- Contents -- Contributors -- Acronyms -- Part I: Introduction -- Chapter 1: The METROPOLE Project - An Integrated Framework to Analyse Local Decision Making and Adaptive Capacity to Large-Scale Environmental Change: Decision Making and Adaptation to Sea Level Rise in Santos, Brazil -- 1.1 Introduction -- 1.2 Background -- 1.3 The METROPOLE Project -- 1.4 Sea Level Rise and Adaptation Options: The Case of Santos, Sao Paulo/Brazil -- 1.5 Adaptive Capacity Index (ACI) Analysis Sao Paulo/Brazil -- 1.6 Conclusions and Final Remarks -- References -- Part II: Current Environmental Patterns and Projections in the Study Area -- Chapter 2: Patterns of Evolution of Frontal Systems Along the South-Southeastern Brazilian Coast -- 2.1 Introduction: Typical Meteorological and Oceanic Conditions -- 2.2 Frontal System -- 2.3 Effects of a Frontal System -- 2.4 Variability of the Mean Sea Level -- 2.5 Characterization of Extreme Sea Level Events in Santos and Their Correspondence with Synoptic Meteorological Conditions -- 2.6 Numerical Modelling of Meteorological Tides in the Western Region of the South Atlantic -- 2.7 Case Study: Effects of the Fronts of September 2009 -- 2.8 Conclusions -- References -- Chapter 3: Patterns of Extreme Precipitation in Santos -- 3.1 Introduction -- 3.2 Material and Methods -- 3.3 Results -- 3.4 Final Remarks -- References -- Chapter 4: Projections of Climate Change in the Coastal Area of Santos -- 4.1 Introduction -- 4.2 Downscaling of Global Climate -- 4.2.1 Validation of the Downscaling -- 4.2.1.1 Simulated Climatology -- 4.2.1.2 Frequency Distribution -- 4.2.2 Projections of Climate Change -- 4.2.2.1 Mean Temperature and Precipitation -- 4.2.2.2 The Frequency Distribution -- 4.2.2.3 Trends of the Climatic Extreme Indices -- 4.2.2.4 Trends in Storms.

PurposeCommunication within a public organization is a fundamental aspect considering its contribution both to organizational well-being and – as highlighted by recent literature – to the improvement of relations with external users. This paper aims at analyzing the relevance of different dimensions of communication and the relationship between communication and citizens' satisfaction.Design/methodology/approachThe study is based on data collected through questionnaires (303; 86%) filled in by the public personnel of an Italian local government to verify the communication dimensions relevance. The authors applied the OLS method to test the relationship between communication dimensions and citizens' satisfaction (deriving from the municipality's customer satisfaction survey system, which collected 3,708 questionnaires).FindingsThe authors show that four of the five communication dimensions considered are particularly relevant and that two of them ("interpersonal communication" and "organizational communication") positively influence the level of satisfaction of users of local public services (citizens' satisfaction), also countering the negative perception of certain sectors (e.g. taxes and local taxation, traffic police). The conclusion also highlights some limitations of the work.Originality/valueThe study brings new insights into the impact of communication (as an element of public employee well-being) on citizen satisfaction, leading to some useful implications for public managers.

Abstract. Although rainfall-triggered landslides are initiated by subsurface hydro-mechanical processes related to the loading, weakening, and eventual failure of slope materials, most landslide early warning systems (LEWSs) have relied solely on rainfall event information. In previous decades, several studies demonstrated the value of integrating proxies for subsurface hydrologic information to improve rainfall-based forecasting of shallow landslides. More recently, broader access to commercial sensors and telemetry for real-time data transmission has invigorated new research into hydrometeorological thresholds for LEWSs. Given the increasing number of studies across the globe using hydrologic monitoring, mathematical modeling, or both in combination, it is now possible to make some insights into the advantages versus limitations of this approach. The extensive progress demonstrates the value of in situ hydrologic information for reducing both failed and false alarms through the ability to characterize infiltration during – as well as the drainage and drying processes between – major storm events. There are also some areas for caution surrounding the long-term sustainability of subsurface monitoring in landslide-prone terrain, as well as unresolved questions in hillslope hydrologic modeling, which relies heavily on the assumptions of diffuse flow and vertical infiltration but often ignores preferential flow and lateral drainage. Here, we share a collective perspective based on our previous collaborative work across Europe, North America, Africa, and Asia to discuss these challenges and provide some guidelines for integrating knowledge of hydrology and climate into the next generation of LEWSs. We propose that the greatest opportunity for improvement is through a measure-and-model approach to develop an understanding of landslide hydro-climatology that accounts for local controls on subsurface storage dynamics. Additionally, new efforts focused on the subsurface hydrology are complementary to existing rainfall-based methods, so leveraging these with near-term precipitation forecasts is a priority for increasing lead times.

Abstract. Uncertainty in rainfall datasets and landslide inventories is known to have negative impacts on the assessment of landslide-triggering thresholds. In this paper, we perform a quantitative analysis of the impacts of uncertain knowledge of landslide initiation instants on the assessment of rainfall intensity–duration landslide early warning thresholds. The analysis is based on a synthetic database of rainfall and landslide information, generated by coupling a stochastic rainfall generator and a physically based hydrological and slope stability model, and is therefore error-free in terms of knowledge of triggering instants. This dataset is then perturbed according to hypothetical reporting scenarios that allow simulation of possible errors in landslide-triggering instants as retrieved from historical archives. The impact of these errors is analysed jointly using different criteria to single out rainfall events from a continuous series and two typical temporal aggregations of rainfall (hourly and daily). The analysis shows that the impacts of the above uncertainty sources can be significant, especially when errors exceed 1 day or the actual instants follow the erroneous ones. Errors generally lead to underestimated thresholds, i.e. lower than those that would be obtained from an error-free dataset. Potentially, the amount of the underestimation can be enough to induce an excessive number of false positives, hence limiting possible landslide mitigation benefits. Moreover, the uncertain knowledge of triggering rainfall limits the possibility to set up links between thresholds and physio-geographical factors.

AbstractThe positioning of quality detection points as well as the frequency of sampling is a crucial aspect for the implementation of Water Safety Plans (WSPs), which have been proposed worldwide to ensure water quality and to minimize the risk from contamination in water distribution networks (WDNs). In this regard, some international legislations and best practices about quality of drinking water suggest very fine sampling frequencies, but they do not specify where the detection points should be located in a WDN. In this paper, three different approaches, based on empiricism, optimization and topology, respectively, were applied to locate detection quality points in a WDN. The comparison highlighted that empirical approach commonly adopted by water utility practitioners is unsatisfactory. The optimization-based approach, although performing significantly better, is difficult to apply, since it requires a calibrated hydraulic model. The topological approach, based on the use of the betweenness centrality and not requiring any hydraulic information and simulation, proves to be effective, and it can be easily adopted by water utilities to identify the location for quality detection points, due to its simplicity compared with the optimization-based approach.

The positioning of quality detection points as well as the frequency of sampling is a crucial aspect for the implementation of Water Safety Plans (WSPs), which have been proposed worldwide to ensure water quality and to minimize the risk from contamination in water distribution networks (WDNs). In this regard, some international legislations and best practices about quality of drinking water suggest very fine sampling frequencies, but they do not specify where the detection points should be located in a WDN. In this paper, three different approaches, based on empiricism, optimization and topology, respectively, were applied to locate detection quality points in a WDN. The comparison highlighted that empirical approach commonly adopted by water utility practitioners is unsatisfactory. The optimization-based approach, although performing significantly better, is difficult to apply, since it requires a calibrated hydraulic model. The topological approach, based on the use of the betweenness centrality and not requiring any hydraulic information and simulation, proves to be effective, and it can be easily adopted by water utilities to identify the location for quality detection points, due to its simplicity compared with the optimization-based approach.

Sea-level rise (SLR) poses a range of threats to natural and built environments in coastal zones around the world. Assessment of the risks due to exposure and sensitivity of coastal communities to coastal flooding is essential for informed decision-making. Strategies for public understanding and awareness of the tangible effects of climate change are fundamental in developing policy options. A multidisciplinary, multinational team of natural and social scientists from the USA, the UK, and Brazil developed the METROPOLE Project to evaluate how local governments may decide between adaptation options associated with SLR projections. METROPOLE developed a participatory approach in which public actors engage fully in defining the research problem and evaluating outcomes. Using a case study of the city of Santos, in Brazil, METROPOLE developed a method for evaluating risks jointly with the community, comparing 'no-action' to 'adaptation' scenarios. At the core of the analysis are estimates of economic costs of the impact of floods on urban real estate under SLR projections through 2050 and 2100. Results helped identify broad preferences and orientations in adaptation planning, which the community, including the Santos municipal government, co-developed in a joint effort with natural and social scientists.