Curated Content

Le Résumé à l’intention des décideurs reprend les principales conclusions du Rapport spécial sur la gestion des risques de catastrophes et de phénomènes extrêmes pour les besoins de l’adaptation au changement climatique (SREX). Les auteurs du Rapport ont évalué les textes scientifiques traitant d’un éventail de questions, des liens entre l’évolution du climat et les phénomènes météorologiques et climatiques extrêmes (les «extrêmes climatiques») aux répercussions de ces phénomènes sur la société et le développement durable. L’analyse a porté sur les interactions des facteurs clima-tiques, environnementaux et humains qui peuvent occasionner des dommages et des catastrophes, sur les possibilités de gérer les risques associés à de tels dommages et catastrophes et sur le rôle majeur que les facteurs indépendants du climat jouent dans l’ampleur des impacts. Les notions essentielles dont il est question dans le Rapport SREX sont défi-nies dans l’encadré SPM.1.

Notes and Technical Details on Chapter 3 Figures

Annex I: Authors and expert reviewers

Annex II: Glossary of Terms

Annex III: Acronyms

Annex IV: List of Major IPCC Reports

In this chapter, case studies are used as examples of how to gain a better understanding of the risks posed by extreme weather and climate-related events while identifying lessons and best practices from past responses to such occurrences. Using the information in Chapters 1 to 8, it was possible to focus on particular examples to reflect the needs of the whole Special Report. The chosen case studies are illustrative of an important range of disaster risk reduction, disaster risk management, and climate change adaptation issues. They are grouped to examine representative types of extreme events, vulnerable regions, and methodological approaches.

This chapter focuses on the implications of changing climate extremes for development, and considers how disaster risk management and climate change adaptation together can contribute to a sustainable and resilient future. Changes in the frequency, timing, magnitude, and characteristics of extreme events pose challenges to the goals of reducing disaster risk and vulnerability, both in the present and in the future. Enhancing the capacity of social-ecological systems to cope with, adapt to, and shape change is central to building sustainable and resilient development pathways in the face of climate change. The concept for social-ecological systems recognizes the interdependence of social and ecological factors in the generation and management of risk, as well as in the pursuit of sustainable development. Despite 20 years on the policy agenda, sustainable development remains contested and elusive (Hopwood et al., 2005). However, within the context of climate change, it is becoming increasingly clear that the sustainability of humans on the Earth is closely linked to resilient social-ecological systems, which is influenced by social institutions, human agency, and human capabilities (Pelling, 2003; Bohle et al., 2009; Adger et al., 2011).

A need to cope with the risks associated with atmospheric processes (floods, droughts, cyclones, and so forth) has always been a fact of human life (Lamb, 1995). In more recent decades, extreme weather events have increasingly come to be associated with large-scale disasters and an increasing level of economic losses. Considerable experience has accumulated at the international (as well as local and national) level on ways of coping with or managing the risks. The same cannot be said for the risks associated with anthropogenic climate change. These are new risks identified as possibilities or probabilities. Acceptance of climate change and its growing impacts has led to a stronger emphasis on the need for adaptation, as exemplified, for example, in the Bali Action Plan (adopted at the 13th Session of the Conference of the Parties to the UNFCCC (UNFCCC, 2007a) and the Cancun Agreements of December 2010. The international community is thus faced with a contrast between a long record of managing disasters and the risks of ‘normal’ climate extremes, and the new problem of adaptation to anthropogenic climate change and its associated changes in variability and extremes. It has been asked how the comparatively new field of anthropogenic climate change adaptation (CCA) can benefit from the longer experience in disaster risk management (DRM). That question is a major focus of this Special Report.

This chapter assesses how countries are managing current and projected disaster risks, given knowledge of how risks are changing with observations and projections of weather and climate extremes, vulnerability and exposure, and impacts. It focuses on the design of national systems for managing such risks, the roles played by actors involved in the system, and the functions they perform, acknowledging that complementary  actions to manage risks are also taken at local and international level.

Disasters occur first at the local level and affect local people. These localized impacts can then cascade to have national and international ramifications. As a result, the responsibility for managing such risks requires the linkage of local, national, and global scales. Some disaster risk management options are bottom-up strategies, designed by and for local places, while other management options are products of global negotiations that are then implemented through national institutions to local levels. Institutions, actors, governance, and geographic units of analysis are not uniform across these scales. Even within each scale there are differences. While some communities are able to cope with disaster risks, others have limited disaster resilience and capacity to cope with present disaster risk let alone adapt to climate variability and extremes. This is the topic of this chapter: to present evidence on where disasters are experienced, how disaster risks are managed at present, and the variability in coping mechanisms and capacity in the face of climate variability and change, all from the perspective of local places and local actors.

The chapter explores three themes:

• how disaster risks are managed at present;
• how the impact of climate extremes threatens human security at the local level;
• and the role of scale and context in shaping variability in vulnerability, coping, adaptive capacity, and the management of disaster risks and climate extremes at the local level.

Chapter 3 evaluates observed and projected changes in the frequency, intensity, spatial extent, and duration of extreme weather and climate events. This physical basis provides a picture of climate change and extreme events. But it does not by itself indicate the impacts experienced by humans or ecosystems. For example, for some sectors and groups of people, severe impacts may result from relatively minor weather and climate events. To understand impacts triggered by weather and climate events, the exposure and vulnerability of humans and ecological systems need to be examined. The emphasis of this chapter is on negative impacts, in line with this report’s focus on managing the risks of extreme events and disasters. Weather and climate events, however, can and often do have positive impacts for some people and ecosystems

This chapter addresses changes in weather and climate events relevant to extreme impacts and disasters. An extreme (weather or climate) event is generally defined as the occurrence of a value of a weather or climate variable above (or below) a threshold value near the upper (or lower) ends (‘tails’) of the range of observed values of the variable. Some climate extremes (e.g., droughts, floods) may be the result of an accumulation of weather or climate events that are, individually, not extreme themselves (though their accumulation is extreme). As well, weather or climate events, even if not extreme in a statistical sense, can still lead to extreme conditions or impacts, either by crossing a critical threshold in a social, ecological, or physical system, or by occurring simultaneously with other events. A weather system such as a tropical cyclone can have an extreme impact, depending on where and when it approaches landfall, even if the specific cyclone is not extreme relative to other tropical cyclones. Conversely, not all extremes necessarily lead to serious impacts.