Natural Hazards and Risk

Natural hazards are processes that occur in nature that threaten the safety, health, and economic interests of human beings. People have often regarded the natural processes as the causes of their losses or the sources of imminent threat. The most dramatic of these events are either geomorphologic processes (earthquakes, volcanic eruptions, landslides, and others) or meteorological processes (hurricanes, tornados, river floods, and others), and these attract widespread attention, but occasionally some derive from complex processes (wildfires, coastal inundation, and other climate change exacerbated processes) or are merely more subtle because they develop slowly or incur slowly appearing changes (such as in droughts, freeze events, infestations [by animals or plants], or disease outbreaks). The likelihood that a particular type of event will occur in a specific location is called risk, and this probability will influence the potential for human exposure in occupied landscapes. The populating of “risky” landscapes creates the hazard, which exists only when human interests are threatened. In this way, “hazard” reflects a measurement of the potential for loss. If humans and their valuables are not present (i.e., potentially exposed to a hazardous event), there is no hazard (statistically speaking). Geographers’ interest in hazard, beyond understanding geophysical processes, stems from the recognition of the importance of human processes (economic, political, sociological, psychological, and others) in the creation and response to hazardous circumstances. The adoption of the “human ecology” perspective (originating in the discipline of sociology) in the 1920s by Harlan Barrows and others established a tradition of analysis of the interaction of physical and human processes. Gilbert White’s scholarship, beginning in the 1940s, opened the policy realm to rational management of human processes and our relationships to the geographies of natural processes. Since then, the geographic perspective of hazards has diversified in a number of ways. Not only has the literature expanded in terms of the sources of hazard but also in terms of critical evaluation of the deeper causes behind the decisions that increase hazard. The past forty years of scholarship have employed increasingly sophisticated social, political, economic, and philosophical models to understand why people are driven to live in places and in ways that increase the likelihood that they will be impacted by detrimental conditions. In geography, in particular, geographic information science and geospatial technologies have enhanced efforts to understand and reduce hazard.