The purpose of this module is to understand the nature, distribution, and impacts of hazards and disasters worldwide and to examine how global changes will affect human vulnerability to such events. To do so, we address this complex subject through the following five questions (see also Cutter 1996):

1. Are societies becoming more vulnerable to environmental hazards and disasters? If so, which hazards may intensify in the future as a consequence of global environmental changes?
2. What social/physical factors influence changes in human occupance of hazard zones?
3. How do people respond to environmental hazards and what accounts for differential adjustments (in the short term) and adaptation (in the longer term)?
4. How do societies mitigate the risk of environmental hazards and prepare for future disasters?
5. How do local risks and hazards become the driving forces behind global environmental changes?

    In this unit, we lay the groundwork to address these questions. We begin by taking a critical look at people’s perception of hazards and the implications of different perceptions on the measurement of hazard trends and on the individual, communal, and societal responses to hazards. Building upon that critical awareness, we then examine some commonly used terms and concepts in order to have a common language with which to speak about past and future hazards trends and the ways in which we attempt to lessen the dangers of living in an ever-changing world. In this module, we use focus issues to highlight problematic aspects of being confronted with hazards. You may want to discuss the questions that accompany each focus issue with your classmates.
 
 

When is Something a Hazard?

 
    Before we look at specific hazards, hazard characteristics, and trends in hazard occurrences, let’s begin with a simple yet profound question -- When is something a hazard? You may think it’s a silly question. Floods, earthquakes, severe thunderstorms, pesticides, and toxic or oil spills immediately come to mind, somehow implying that all these things are inherently hazardous. At least two arguments challenge the notion that things are inherently hazardous, however. The first is that if no people (or things that people value, such as their homes and belongings, a beautiful landscape, or a clean beach) are harmed, then a phenomenon isn’t hazardous; the event would simply happen without anyone or anything being affected negatively. "Well," you might say, "but what about animals or ecosystems?" That question simply proves the point; it indicates that you value animals or ecosystems as important, precious, or beautiful and that you feel something could harm them. From this perspective, a severe windstorm that topples trees, uproots vegetation, and injures creatures on the ground would be a hazard to animals and ecosystems.

    The second argument challenging the notion that certain phenomena are inherently hazardous is a little less obvious but even more important than the first: what is a hazard to you may not be a hazard for me. Here are a few examples.
 

1. But, after all, there is at least one or two things about that weather (or, if you please, effects produced by it) which we residents would not like to part with. If we hadn’t our bewitching autumn foliage, we should still have to credit the weather with one feature which compensates for all its bullying vagaries -- the ice-storm: when a leafless tree is clothed with ice from the bottom to the top -- ice that is as bright and clear as crystal; when every bough and twig is strung with ice-beads, frozen dewdrops, and the whole tree sparkles cold and white, like the Shah of Persia’s diamond plume. Then the wind waves the branches and the sun comes out and turns all those myriads of beads and drops to prisms that glow and burn and flash with all manner of colored fires, which change and change again with inconceivable rapidity from blue to red, from red to green, and green to gold -- the tree becomes a spraying fountain, a very explosion of dazzling jewels; and it stands there the acme, the climax, the supremest possibility in art or nature, of bewildering, intoxicating, intolerable magnificence. One cannot make the words too strong.
-- Mark Twain. 1876. The Weather -- Address at the New England’s Society’s 71st Annual Dinner, New York City, December 22, 1876. (Cited from New England’s disastrous weather, p.226.)
 
2. They like to tell the one about the farmer selling apples under a big sign that reads ‘Apples from Chernobyl.’ ‘You must be mad,’ a passerby said. ‘No one wants to buy apples from Chernobyl.’ ‘Sure they do,’ the farmer said. ‘Some buy them for their mothers-in-law, some people buy them for their wives.’ Others downplay the risk. ‘All I know is that we’ve been eating the food around here for almost 10 years, and we feel fine,’ said Olina Nikolayeva, 65, one of several hundred people who have moved back into the Ukrainian village of Opachichi, 15 miles from the reactor. ‘You can eat the apples, but you have to bury the seeds deep in the ground,’ Nikolayeva said. ‘You can eat mushrooms, but only up to 10 kilograms. And if you feel too much radiation, you have to drink some vodka.’
-- Excerpt from Filipov, David. 1996. In Chernobyl soil, fatalism thrives. The Boston Sunday Globe, April 21: 17. © Reprinted courtesy of David Filipov. The Boston Globe 1996.
 
3. I grew up in the 1970s in Taipei. Every summer of my childhood it was unbearably hot and humid, and quite often a typhoon attacked Taiwan. Even though this was twenty years ago, I can vividly recall what happened to our home and neighborhood year after year until the government constructed underground waterworks. It happened almost every June. The rain brought by the typhoon flooded the school up to its second floor. All the houses in our compound were covered with water on the first floor. As soon as we were warned to expect a downpour, we started to clear the gutter around the house and tried to place our furniture on higher ground. All we could do was to grab our valuables; refrigerators, beds, and the piano all got soaked in the water. We had to spend the nights at our neighbors’ home on the third floor. We counted the hours in the dark in fear and simply could do nothing else because of the black out and the suspension of the water supply. Some neighbors were more happy-go-lucky than we were and went as far as to sit around a table playing Majong by candlelight to kill time. The ruined furniture, electric appliances, and mud from the hillside formed a heap on the street. The talk of the day centered on how much each family had lost and whose car had been soaked with mud and water. The neighborhood stores got a lot of business since everyone rushed to buy and hoard food. The neighbors got acquainted with each other after going through the same experiences. After a while, everything went back to normal. Flooding was an event to go through each summer. It would be a surprise if there was no devastating typhoon in June. The government was never blamed, but instead when residents received food sent by the agencies, they expressed gratitude toward the government. The children were happy not to have to go to school. It was an opportunity for them to go rafting on the flooded streets. Seldom would neighbors speak of moving away because they could not afford to buy an apartment elsewhere. The nightmares of typhoons finally stopped haunting us in 1986 when the government finished the underground water works.
-- A graduate student at Taiwan National University. 1996. Personal account of typhoon and flood memories. Provided by Nora Chiang, Taiwan National University.
 
4. I think the economic logic behind dumping a load of toxic waste in the lowest wage country is impeccable and we should face up to the fact that ... underpopulated countries such as Africa are vastly underpolluted.
-- Lawrence Summers (Former Chief Economist of the World Bank) December 1991; cited in Puckett, Jim. 1994. Disposing of the waste trade: Closing the recycling loophole. The Ecologist 24, 2: 53-58 (quote from p.53).

5. Floods in Bulozi (Western Zambia)

           -- Excerpt from a poem translated from Sibetta, O.K. 1983. Fa Manunga Wa Lyambai, Lusaka, Neczam. Source: Namafe, Charles and Frances Slater. 1995. Floods: Friends or enemies? Geographical Education 8, 3: 57-62 (complete poem on p.57) 

It is floodtime in Bulozi  There is the floodplain clothed in the water garment  Everywhere there is water!  there is brightness!  there are some sparkles!  Waves marry with the sun’s glory  Birds fly over the floods slowly,  they are drunken with cold air  they watch a scene which comes but once a year  floods are tasty (nice, beautiful)  Bulozi is the floods’ place of abode  every year the floods pay us a visit.

A Lozi does not beg for floods  We do not turn the herbs to have floods  We do not practice witchcraft whatsoever  They are floodwaters indeed!  The floods know their home area.  Floods are ours  the floods themselves  they (floods) know their own route  they know their home area  they know where they’re needed  they know where they are cared for  And when we ourselves see them  we are inflated with happiness  our hearts become lighter  we do not fear floods ...

 

    We should inject a note of caution. To say that a hazard to some may be a completely different experience for another is a heavily subjectivist position, meaning that reality is simply what we say or think it is; it’s all in our minds and there is no "external" foundation for whatever we perceive. To be sure, there are some thinkers who maintain such a position, but we do not adopt it in this module. Whether or not you perceive driving without a seat belt as hazardous, it does kill people; whether or not you perceive smoking as a hazard, countless studies show that your health is negatively affected by smoking. By analogy, to take a purely objectivist position and say that hazard perception is irrelevant because there is only one external reality and that’s all we need to worry about is insensitive to the reality of human beings and their experiences. Although in this module we repeatedly emphasize the importance of hazard perception, it is no longer the hottest or most pressing aspect of hazard studies.

    Our perceptions of a hazard are influenced by factors such as personal experience with a hazard, varying knowledge of a hazard, different outlooks on the world (God, nature, technology, society, government, self, etc.), culture, gender, wealth, age, the personal and professional roles we have taken on, and adjustments and adaptations to the hazard we have managed. When we ask big questions like "Are things getting better or worse?" or "Is the world becoming more disastrous?" there can be no straightforward answer. We have to question the point of view from which someone would answer these questions, and we have to be aware of the context in which a statement is being made. For example, the answers to such questions are likely to differ between an insurer, an insured home owner, and someone who just lost insurance -- even though they may all speak about property losses from floods.

    Similarly, responses to hazards will differ depending on people’s hazard perception and personal circumstances. If you are 10 years old and a major blizzard keeps you at home because schools are closed, you might celebrate the day by building a snowman or hanging out with friends. If you are a parent who is expected to be at work and can’t afford the loss of pay or a babysitter, that blizzard is not a source of joy!

    The same caution about perceptions and responses applies to hazards associated with global environmental change. Scientists say that the effects of global climate change, for example, are likely to benefit some regions of the world while harming others. Superimposed on this unevenness in the effects of global change are differing perceptions of such changes, i.e., what we do and don’t perceive, and how we judge these changes.

    When we look at hazard trends, these differing hazard perceptions put us in a quandary. On the one hand we would like to appreciate differences in perceptions; on the other hand, in order to discern trends, we need measures of frequency or occurrence, and these measures need to be based on the same definition of a hazard over time to ensure comparability. In the next section we provide some common definitions of hazard-related terminology to allow us to look at trends from a common viewpoint and to connect with the scientific hazard literature. We will continue to point out, however, in the text and in the activities, how differences in perception of and responses to hazards and environmental change affect the discussion of trends and responses to hazards.

 
 

Establishing a Common Language: Some Definitions

 
    The terms risk, hazard, and disaster are often used interchangeably although each has a precise and distinct meaning. Hazard is the broadest term and reflects a potential threat to humans as well as the impact of an event on society and the environment. Risk refers to the likelihood or probability of occurrence of an event. Hazards include risk (i.e., a probability), impact (or magnitude), and contextual (sociopolitical) elements. Quite simply, hazards are threats to people and the things they value (Cutter 1993). They are in part socially constructed by people’s perceptions and their experiences. Moreover, people contribute to, exacerbate, and modify hazards. Thus, hazards can vary by culture, gender, race, socioeconomic status, and political structure as well. Disasters, in contrast to risks and hazards, are singular or interactive hazard events (like those mentioned in the first section) that have a profound impact on local people or places either in terms of injuries, property damages, loss of life, or environmental impacts. Finally, vulnerability is the potential for loss or the capacity to suffer harm from a hazard. The term, used in various ways by researchers, can generally be applied to individuals, society, or the environment.
 

 

Types of Hazards

 
    It is the interaction among nature, society, and technology that produces hazards, risks, and disasters, many of which may be amplified by global environmental changes currently underway. Hazards arise from many different sources (summarized in Table 1 below), and considerable research effort has focused on developing typologies of hazards to establish some order in an ever-increasing list of hazards (e.g., Hohenemser, Kates, Slovic 1985; Cutter 1993). Many of the typologies use the causes or origins of hazard events as the classifying principle. In most cases, however, hazards are multi-causal so that most researchers now refrain from proposing single cause-based typologies of hazards. Yet it is possible to classify hazards according to the area in which they mainly originate. Those originating from natural processes are referred to as natural hazards. Examples include earthquakes, volcanic eruptions, floods, hurricanes, blizzards, and tornadoes. These phenomena vary regionally and seasonally and may trigger secondary hazards. For example, landslides and tsunamis can follow earthquakes. Thunderstorms may be accompanied by heavy rains that can cause mudflows, flash floods, and conventional flooding. Hazards also arise from rather common natural events such as hail, coastal erosion, heat waves, and droughts, all of which can cause considerable damage to the natural environment and society.

    Other hazards originate in social systems and include terrorism (domestic bombing such as the Oklahoma City incident as well as international acts of terrorism), warfare, epidemics (such as the Ebola virus), and civil disorder or ethnic violence (such as in Bosnia and Rwanda). The interaction of society, technology, and natural systems produces another type of hazard often called technological hazards. Nuclear power plant accidents such as the one at Chernobyl, industrial accidents like the one in Bhopal, oil spills, and hazardous materials spills all fall under in this category. Finally, there is a group of hazards that do not stem from one event but rather arise from more chronic conditions, including famine, resource degradation, pollution, and large-scale toxic contamination. These chronic hazards are the type that will be most affected by changes in the global environment. A broader term like human-induced hazards is necessary to encompass the last two categories of hazards (technological and chronic types of dangers) and the above-mentioned hazards like warfare, terrorism, and epidemics.
 

    Magnitude describes the strength or force of an event. In order to assess the magnitude, one must first have a base line for comparison. In the case of floods for example, magnitude is often described as the maximum height of flood waters above average sea level, flood stage, or simply above ground. For seismic events, magnitude is measured on the Richter scale which is an estimate of the amount of energy released by an earthquake (see Table 2). But the strength of an event can also be measured by more than its physical characteristics. Intensity provides a useful measure of the severity of an event based on the subjective human experience of it. For example, the Modified Mercalli scale (see Table 3) measures the intensity of earthquakes based on damage to structures and the human experience of the event. For hurricanes, the Saffir-Simpson scale is a measure of both intensity and magnitude. It evaluates hurricane strength and impact based on a five-point scale with Category 5 hurricanes listed as the most severe and destructive (Table 4).

  Speed or rate of onset refers to the length of time between the first appearance of the event and its peak. We can think of rapid onset events such as tornadoes and nuclear power plant accidents or slow onset hazards such as soil erosion, pollution, or drought. The speed of onset is a characteristic of a hazard that is crucial in our efforts to avoid some of the worst impacts of hazards. In other words, much of modern hazard management effort is geared toward improving our ability to detect signs of an impending hazard event as early as possible so as to expand the time between signal detection and the peak of the event for warning and possibly evacuating vulnerable populations.

    Temporal spacing describes the sequencing and seasonality of events. Some hazards are quite random in their timing (industrial accidents, volcanic eruptions), whereas other hazards have a seasonal or regular periodicity (tornadoes, hurricanes). The implications of temporal spacing for hazard management are quite clear; if you can expect certain hazards to be more likely in certain seasons or at relatively regular intervals, you can be ready to communicate the risk to potentially affected populations in a timely manner, and mount the necessary efforts to allow you to respond more quickly and effectively to an emergency. Hurricane Bertha in July 1996 serves as a good example. After much criticism of the delayed federal response to Hurricane Andrew, the federal government issued a Presidential statement before Bertha’s landfall that the emergency response teams were in place and ready for whatever may come (National Public Radio, July 12, 1996). Randomly occurring hazards are much more challenging to emergency response agencies because they require a low level of preparedness at all times for the rare case that requires quick, efficient, and effective responses.

    The next two characteristics of a hazard allow us to examine its geographic extent. Areal extent is a measure of the space covered by an event. Some hazards like a tornado or a small gasoline spill may have a small areal extent; others such as droughts or major nuclear accidents (like the one at Chernobyl in 1986), affect large geographic regions. Spatial dispersion refers to the distribution of hazards over the space in which they can occur. Spatial dispersion is a useful measure of the geography of hazards because it differentiates between hazards that occur within a particular region and those that are more widespread. For example, although tornadoes can occur just about anywhere in the US, they primarily occur in the "tornado belt" of the Central Plains from Texas to Nebraska.

    A final hazard characteristic refers to the nature of exposure, which is an important concern in reducing risk and mitigating the impact of hazards. For example, is exposure voluntary or involuntary? With many environmental hazards, we have little control over whether or not we are exposed to them; we can neither control the weather nor stop earthquakes. On the other hand, we do have some degree of choice (voluntariness) about where we live (e.g., floodplains, coastal regions), what kind of food we eat (e.g., organically or commercially grown produce), or what types of activities we engage in (e.g., scuba diving, using drugs, or smoking) that directly affect our vulnerability to some hazards. Parts 1 and 2 of Focus Issue 1 highlight issues of frequency, magnitude, and the nature of exposure for flood hazards and provide a concrete example from South Africa.

The Role of Geography in Hazard and Global Change Research

 
    At the beginning of this unit, we posed five questions that we will address in this module:

1. Are societies becoming more vulnerable to environmental hazards and disasters? If so, which hazards may intensify in the future as a consequence of global environmental changes?
2. What social/physical factors influence changes in human occupance of hazard zones?
3. How do people respond to environmental hazards and what accounts for differential adjustments (in the short term) and adaptation (in the longer term)?
4. How do societies mitigate the risk of environmental hazards and prepare for future disasters?
5. How do local risks and hazards become the driving forces behind global environmental changes?

    These developments in the hazards field have been influenced by and have helped to shape the global environmental change research agenda. For example, research has focused on the difficulty of discerning natural versus human shares in causing global changes, the heavily politicized and ethically loaded debate over how to mitigate the impacts of global change, the role of technology in causing and responding to global change, and the economic challenges and social choices we face in responding to global changes. The hazard research agenda has been extended to include large-scale, regional-to-global, slow-onset, and cumulative hazards in response to the needs of the global change research community (Burton, Kates and White 1993; Mitchell 1989). Likewise, the global change community has borrowed impact assessment methodologies, notions of risk and uncertainty, and other concepts and approaches from hazards research to address global problems.

    In addressing these complex questions, geography can play a pivotal role. Both the hazards and global change fields have traditionally been interdisciplinary and in the last few years, geographers have become increasingly involved. Geographic scale is crucial to understanding hazards distribution, impact, and reduction (Cutter 1994). The discovery of new hazards and the rediscovery of older ones with more dispersed and cumulative impacts necessitate the globalization of risk and hazard management systems. Unfortunately, because of the enormous difficulties of conducting truly global studies, much hazard research continues to be in the form of local or regional case studies. The articulation between local and global processes will continue to challenge geographers and other researchers.

    Geographers also contribute their expertise on the linkages among physical processes and human contexts. This helps us to understand better the causal mechanisms that bring about hazards and disasters, and is of great importance to hazard management. This expertise also helps define the areal extent of the hazard, one of the important characteristics of hazards.

    In summary, many linkages exist between hazards and global environmental change research, and geographers have much to contribute. In fact, geographers with expertise in environment-society interactions at different scales, an interest in historical and future trends, and a keen awareness of the ways in which different societies perceive these relations are situated at the intersection of hazards and global change research.