This chapter explores the root causes of large-scale disasters and how those root causes might be addressed to reduce disaster risk. Definitions are given, indicating that the term “natural disaster” might be a misnomer because disasters tend to require human input to occur, making few disasters be truly “natural.” Then, case studies of United Kingdom floods in 2000 and El Salvador earthquakes in 2001 are used to demonstrate vulnerability, the human input to disasters, as being the root cause of large-scale disasters. Vulnerability is shown to arise from population, economic, and political factors. As methods of dealing with the root cause of vulnerability, “localizing disaster risk reduction” and “living with risk” are described in theory and applied in practice to warning systems and education tools. To address root causes of large-scale disasters, opportunities need to be created for linking disaster risk reduction with wider livelihoods and sustainability activities.

Definitions and context

Defining disasters

Chapter 1 defines “a large-scale disaster” by the number of people affected by it and the extent of the geographic area involved: either 100 to 1,000 people need to be adversely affected, such as by being displaced, injured, or killed, or else the disaster's adverse effects must cover 10 to 100 km2.