Drought Risk and Hazard

Drought is a complex concept with both physical and socially constructed components. The idea of a drought conjures a popular image of cracked brown earth, fallow agricultural fields, and suffering human communities. This realistic image confuses the physical drought hazard with the social impacts of drought in contexts with high drought risk. Drought does not lend itself to a single, universal definition because drought has different spatial and temporal characteristics in distinct climates and regions. Drought hazard refers to the physical phenomenon of a meteorological drought, generally defined as a departure from a long-term precipitation (e.g, rainfall or snowfall) average that results in an impact in a specific place. A drought is a temporary yet recurring phenomenon that occurs in all climates, but occurs with a greater frequency and more severe impacts under certain regional conditions than in others.

Unlike other hazards such as floods and tropical storms, a drought is gradual or “creeping.” Drought hazards are spatially vast and affect more people worldwide than do other “natural” disasters. Notable drought-prone regions of the world include Australia, Northern Mexico, northeast Brazil, Western Africa, and southwestern United States. With respect to drought, Africa experiences the greatest loss of life, Asia has the most people affected, and the West sustains the highest economic damages. Drought can lead to a massive loss of life, famine, desertification, deforestation, loss of livelihood, and migration.

Drought risk refers to the vulnerability associated with the exposure of an individual, a community, or a region to a drought hazard, as well as the capacity of that entity to adapt or respond in an effective way to the drought hazard. A drought hazard does not in itself cause a social disaster. Rather, socioeconomic attributes and policy choices determine whether a meteorological drought will create conditions of high drought risk. For example, in a poor country with a high proportion of subsistence farmers, a drought may imperil the country's overall food security, while in a country with high levels of imported foods and widespread irrigation, a drought may have limited impacts. Drought hazard and risk are therefore separate yet related concepts.