Preface

Human beings are increasingly subjected to risks and phenomena of natural or technological origin that can compromise the balance between the social and natural environments. The Knowledge Society of the 20th century is characterized by the intensification of risks associated with climate change. Potentially devastating risks are our society's biggest problem.

By definition, risk is the value obtained from the assessment of possible consequences (human losses, direct and indirect damages and costs) caused by incidents or accidents, together with the probability of occurrence of hazardous processes due to the conjunction of the factors involved. Risk is a combination of the probability of unfavorable scenarios and their consequences.

In this context, it is possible, and advisable, to evaluate the expected value of these consequences, in order to establish, based on scenarios, procedures for forecasting, preventing, controlling and mitigating the effects of these hazardous processes to people and assets, associated with both natural and technological risks.

Risk analysis, risk evaluation and risk management are the main pieces in the process known as 'Risk Assessment'. Risk assessment can be understood as the joint effort of identifying and analysing potential future events, i.e., risk analysis, and evaluating the acceptability of risk based on the risk analysis, while considering influencing factors, i.e., risk evaluation. In short, risk assessment analyses what can go wrong, how likely it is to happen and, if it happens, what are the potential consequences.

Since this is a multi-disciplinary domain involving various scientific areas, among which geography, Earth and environmental sciences, ecology, engineering, law, economics, sociology and political sciences, this book gathers contributions covering a wide spectrum of topics with regard to their theoretical background and field of application. As part of this process, the resulting assessment of risk may be expressed in both quantitative and qualitative approaches.

Vulnerability to risks varies widely, primarily depending on the capacity of societies to integrate them in the management of their activities, to mitigate their effects and to recover from the disaster. Two major parameters are decisive for ensuring the development of these capacities and the consequent reduction in vulnerability expert knowledge and planning.

It is within the first parameter that one seeks to discern the magnitude of risks and to test new technologies to support the monitoring, evaluation and communication of threats. The concept of risk has, of course, evolved over time, and is now a basic principle in decision-making by politicians, managers, entrepreneurs, builders and civil protection services, in the definition of safety and security systems, completed in safety and emergency plans, and is integrated in crisis management programs associated with accident situations.

Risk assessment is an inherent part of an overall risk management strategy, which attempts to introduce, after a risk assessment, control measures to eliminate or reduce any potential risk-related consequences. This concept is linked today to a new paradigm, in which the technological, social and communicational aspects gain even more relevance.

> **Jorge Rocha, Sandra Oliveira and César Capinha** Institute of Geography and Spatial Planning, University of Lisbon, Lisbon, Portugal

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Section 1

Risk Analysis

Section 1 Risk Analysis

**3**

**Chapter 1**

**1. Introduction**

a first crisis management.

operational instruments.

Management

Introductory Chapter: Risk

*Jorge Rocha, Sandra Oliveira and César Capinha*

question, related to the human perception of risks, arises.

The notion of risk presents itself, nowadays, as one of the most dynamic scientific areas, capturing the attention of researchers from a wide group of disciplines. Studies about the probability of occurrence of an event and its possible consequences are followed by answers that guide the concerns about interventions in relation to the health and safety of populations and the environment. This is why a fundamental

There is a reasonable consensus to consider the age of Renaissance, the discoveries, and the long-distance maritime trade as milestones in the initial consolidation of risk analysis. In the Modern Age, a catastrophe in a European capital, the 1755 earthquake in Lisbon, sparked a debate in Europe around ideas about providence and destiny. This event triggered, from the political power, the implementation of a set of measures to mitigate its social effects as well as protective actions against future earthquakes. The decisions that were made then are a historical example of a response to a natural disaster and an organization model of

Controlling risk in its various forms, for example, management, analysis, evaluation, and mitigation or treatment, among others, has now become a normal act, almost indispensable in proper governance. In the society of risk, the greater awareness of risk inevitably leads to its assessment and a search for answers, with the objective of implementing an adequate management. Whether risks are natural, technological, or other, the inclusion of perception studies in the risk management processes has become a priority for public policies. We can already ask ourselves how we could face the challenges of the present and the future without these

Protection against hazards that may affect the public or the environment has become a right, recognized and demanded by the public opinion, and an indicator of the quality of life and citizenship. From the resigned acceptance of events, we have moved to a phase of intervention by citizens and states to regulate life and

Increasing social responsibility allows recognizing the effects resulting from the impact of different hazards, whether they are natural or anthropogenic. Politicians also started to use the concept of risk as a support device for the control of society

Associated with risk comes the concept of vulnerability that characterizes the potential for loss derived from the impact of hazardous events on a given asset. In certain situations and conditions of uncertainty, the credibility or validity of a quantitative risk analysis based on estimated probabilities becomes problematic. In these circumstances, the vulnerability analysis and management can be an

public and private activities in defense of public health and safety.

and as a complementary device to ensure security.

appropriate and effective alternative.

#### **Chapter 1**
