ABSTRACT
This chapter looks at sustainability from a different perspective. It examines risk as the potential to cause deviation from that preferred path, and security as a form of insurance to prevent that deviation. It focuses on resilience as a system property that describes how difficult it is to change a system state. The chapter provides historical and modern examples of environmental and social collapse and briefly addresses strategies for avoiding collapse. There are three main types of environmental risks. Hydrometeorological events include floods, droughts, mudflows and avalanches, storms, heat waves, cold spells, and wildfires. Geological events include earthquakes and tsunamis, landslides, volcanic eruptions, and sinkhole formation. Biological events include disease, epidemics, and pests and invasive species. One of the primary aims of sustainable development is to reduce risk, thereby increasing longevity and improving human well-being. The chapter discusses the environmental risks that are geological and hydrometeorological, which people collectively refer to as natural hazards.
