Environmental Hazards Methodologies for Risk Assessment and Management

Nicolas R. Dalezios, Nicolas R. Dalezios

• Éditeur: IWA Publishing
• Année: 2017
• ISBN:
  9781780409061
• Sujet: Tecnología e ingeniería
• Sous-sujet: Ciencias aplicadas

From the beginning of 21st century, there has been an awareness of risk in the environment along with a growing concern for the continuing potential damage caused by hazards. In order to ensure environmental sustainability, a better understanding of natural disasters and their impacts is essential. It has been recognized that a holistic and integrated approach to environmental hazards needs to be attempted using common methodologies, such as risk analysis, which involves risk management and risk assessment. Indeed, risk management means reducing the threats posed by known hazards, whereas at the same time accepting unmanageable risks and maximizing any related benefits. The risk management framework involves evaluating the importance of a risk, either quantitatively or qualitatively. Risk assessment comprises three steps, namely risk identification (data base, event monitoring, statistical inference), risk estimation (magnitude, frequency, economic costs) and risk evaluation (cost-benefit analysis). Nevertheless, the risk management framework also includes a fourth step, risk governance, i.e. the need for a feedback of all the risk assessment undertakings. There is currently a lack of such feedback which constitutes a serious deficiency in the reduction of environmental hazards. This book emphasises methodological approaches and procedures of the three main components in the study of environmental hazards, namely forecasting - nowcasting (before), monitoring (during) and assessment (after), based on geoinformatic technologies and data and simulation through examples and case studies. These are considered within the risk management framework and, in particular, within the three components of risk assessment, namely risk identification, risk estimation and risk evaluation. This approach is a contemporary and innovative procedure and constitutes current research in the field of environmental hazards. Environmental Hazards Methodologies for Risk Assessment and Management covers hydrological hazards (floods, droughts, storms, hail, desertification), biophysical hazards (frost, heat waves, epidemics, forest fires), geological hazards (landslides, snow avalanches), tectonic hazards (earthquakes, volcanoes), and technological hazards. This book provides a text and a resource on environmental hazards for senior undergraduate students, graduate students on all courses related to environmental hazards and risk assessment and management. It is a valuable handbook for researchers and professionals of environmental science, environmental economics and management, and engineering. Editor: Nicolas R. Dalezios, University of Thessaly, Greece

© IWA Publishing 2017. Nicolas R. Dalezios. Environmental Hazards Methodologies for Risk Assessment and Management. DOI: 10.2166/9781780407135_001

Part 1

Prolegomena

Chapter 1

Environmental hazards concepts

Nicolas R. Dalezios and Costas Lalenis

1.1 CONCEPTS AND SCOPE OF ENVIRONMENTAL HAZARDS

1.1.1 Concepts of environmental hazards and disasters

Disasters are defined by the United Nations International Strategy for Disaster Risk Reduction (UNISDR, 2005) as “a serious disruption of the functioning of a community or a society causing widespread human, material, economic or environmental losses which exceed the ability of the affected community or society to cope using its own resources”. Similarly, a hazard is defined as “a potentially damaging physical event, phenomenon or human activity that may cause the loss of life or injury, property damage, social and economic disruption or environmental degradation”. This event has a probability of occurrence within a specified period of time and within a given area, and has a given intensity (UNISDR, 2005).

Environmental degradation is one of the major factors contributing to the vulnerability of several sectors, such as environment, society, economy and agriculture, because it directly magnifies the risk of natural disasters. In order to ensure sustainability in the above sectors, a better understanding of the natural disasters and their impacts is essential. A comprehensive assessment of impacts of natural disasters on different sectors requires a multidisciplinary, multi-sectoral and integral approach involving several components and factors. Priority should be given to supporting applied research, since research is necessary to understand the physical and biological factors contributing to disasters. Community-wide awareness and capacity building programs on natural disasters, mainly for farmers and stakeholders should also be included in any research effort. Programs for improving prediction and early warning methods, as well as dissemination of warnings should be expanded and intensified. Moreover, efforts are required to determine the impact of disasters on natural resources. It has been recognized that, although hazards may impact at the local scale, there are increasing international consequences due to global factors, such as climate change, poverty or the rise of mega-cities. Indeed, the losses from natural disasters justify a concern about the sustainability of continuous population growth and wealth development. Nevertheless, the challenge in hazard research is to improve the skills and adopt a broader perspective including global change with the objective to create a safer future environment.

1.1.2 Scope of hazards and disasters

Global warming is likely to bring significant changes in the world’s climate over the coming decades. It is probable that the most significant physical consequences and effects will be experienced in countries highly dependent on natural resource use, which influence activities, such as agricultural development, forestry, wetland reclamation and river management. The overall result is likely to widen the gap between developed and developing regions and countries, since the impact is expected to be most severe on ecosystems already under stress and for regions, which have few spare resources for mitigating or adapting to climate change. The world land-use data of FAO, show that 70% of the global land use is for agriculture, rangeland and forestry. Indeed, agriculture is essential source of income in most developing countries. Moreover, agricultural production, along with other sectors of economy, is highly depended on weather and climate, and is adversely affected by weather and climate-related disasters.

Recent research findings suggest that variability of climate, if encompassing more intense and frequent extremes, such as major large-scale hazards like droughts, heatwaves or floods, results in the occurrence of natural disasters that are beyond our socio-economic planning levels. This is expected to stretch regional response capabilities beyond their capacity and will require new adaptation and preparedness strategies. Disaster prevention and preparedness should become a priority and rapid response capacities to climate change need to be accompanied by a strategy for disaster prevention. Nevertheless, each type of extreme events has its own particular climate, cultural and environmental setting, and mitigation activities must use these settings as a foundation of proactive management (IPCC, 2012). There is an urgent need to assess the forecasting skills for natural disasters affecting agriculture in order to determine those where greater research is necessary. It is well known that lack of good forecast skill is a constraint to improve adaptation, management and mitigation.

In this book the environmental hazards affecting several sectors of the economy are considered under increasing climate variability. The emphasis is on methodologies. It should be stated that current natural disaster management is crisis driven. It is thus realised that there is an urgent research need for a more risk-based management approach to natural disaster planning, which would include a timely and user-oriented early warning systems. Disaster risk zoning is also an essential component of natural disaster mitigation and preparedness strategies. GIS and remote sensing and, in general, geoinformatics are increasingly employed due to the complex nature of databases to facilitate strategic and tactical applications at the farm and policy levels. Therefore, additional research is required to incorporate GIS, remote sensing, simulation models and other computational techniques into an integrated multi-hazard risk management framework for sustainable environment, which includes early warnings of natural disasters (Sivakumar et al. 2005). There should also be more research attention to the impacts of potentially increasing frequency and severity of extreme events associated with global change and appropriate mitigation strategies. Moreover, a revision on existing conventional approaches is required in order to include the major recent research advancements in understanding these complex interrelationships. This revision should emphasize on prediction, monitoring and early warning methods, as well as vulnerability and impact assessment techniques and preparedness and mitigation strategies. In addition, there is a current need for more research into the physical behaviour of the climate system to develop better mitigation strategies.

1.2 A TYPOLOGY AND CLASSIFICATION OF HAZARDS

Hazards can be single, sequential or combined in their origin and effects. Each hazard is characterized by its location, area affected (size or magnitude), intensity, speed of onset, duration and frequency. Hazards can be classified in several ways. A possible classification is between natural, human-induced and human-made hazards. Natural hazards are natural processes or phenomena in the Earth’s system (lithosphere, hydrosphere, biosphere or atmosphere) that may constitute a damaging event (e.g. earthquakes, volcanic eruptions, hurricanes). A classification relates natural hazards to the main controlling factors of the hazards leading to a disaster. They may be hydro-meteorological hazards, which include floods and wave surges, storms, droughts and related disasters, such as desertification. Also geophysical hazards result from anomalies in the Earth’s surface or subsurface, such as earthquakes, tsunamis and volc...