About Module 8

In Unit 1 (Modules 1 to 4), we learned key concepts used throughout the course. In Unit 2 (Modules 5 to 7), we learned about what development is and how it can be sustainable. We now turn to our Unit 3 on global environmental change. Simply put, due mainly to human development, the global environment is currently undergoing major changes – changes that are, in turn, causing major disruption to human systems and environmental systems alike.

Module 8 focuses on natural hazards. Natural hazards are threats of natural events that cause harm to humans or to other things that we care about. Many natural hazards are not initially caused by humans, but the damage inevitably has a strong human component. We start the final sets of modules this way because studying hazards helps us understand environmental impacts on more local scales, giving us valuable perspective on global environmental change.

What will we learn in Module 8?

By the end of Module 8, you should be able to:

• explain the relationship between natural hazards, extreme events, and disasters;
• present and compare several major examples of natural disasters;
• describe factors that make some people and places more vulnerable to specific types of natural hazards;
• explain steps that can be taken to reduce vulnerability to natural hazards and reduce harm from specific extreme events;
• discuss connections between natural hazards and global environmental change.

What is due for Module 8?

There is just one required reading for this module. Next week's Written Assignment will draw on material from Modules 8 and 9.

Questions?

If you have any questions, please post them to our Course Q & A discussion forum in Canvas. I will check that discussion forum often to respond. While you are there, feel free to post your own responses if you, too, are able to help out a classmate. If you have a more specific concern, please send me a message through Inbox in Canvas.

Before we begin, let’s look at some examples of natural disasters. This will help set the tone for the rest of the module and give an understanding of some of the sorts of scenarios we’ll be studying. The four examples presented here are four of the biggest natural disasters of the last decade. A fifth, the 2010 Haiti earthquake, will be discussed in depth later in the module.

2012 Hurricane Sandy, US East Coast (Video- 7:41 seconds)

Hurricane Sandy (also known as Superstorm Sandy) was the most destructive hurricane of the 2012 Atlantic hurricane season. Sandy made landfall in southern New Jersey and became incredible in its size and power. It was a large storm with violent gusts and storm surges that caused major flooding and left millions of people along the East Coast without power. More than 100 people died and tens of thousands of people were injured and relocated. According to NOAA, estimated damage from Sandy is $71 billion, making Sandy the fourth-costliest hurricane in United States history, after Hurricanes Katrina, Harvey, and Maria.

2011 Earthquake and Tsunami, Japan

On March 11, 2011, a magnitude-9.0 earthquake hit northeastern Japan and caused a savage tsunami that engulfed everything in its pathway. About 20,000 people were killed. The quake lifted the seafloor by 30 feet and the tsunami debris was found on US shorelines two years later. The twin disaster caused a meltdown at the Fukushima Daiichi nuclear plant which developed into the world's worst nuclear crisis. Throughout GEOG 030N, we have emphasized human impacts on the environment. It is important to recognize that humans do not cause earthquakes. We certainly do play a large role in determining what the impacts of an earthquake end up being. But the earthquake itself is caused by plate tectonics.

2008 Cyclone Nargis, Myanmar

Myanmar (also known as Burma) is a coastal country in Southeast Asia. On May 2, 2008, Myanmar was hit by a category 4 cyclone named Nargis. The damage caused by Nargis was extreme, both because the cyclone was so powerful and because Myanmar was not well prepared to handle it. Myanmar was not well prepared because it was quite poor and also because its military government was not well-organized for the relief effort. One tragic complication was that the government had bad relations with other countries. After Nargis hit, the international community offered to assist Myanmar with its recovery, but because of its government, this assistance was not easily received.

Officially, Cyclone Nargis caused about 138,000 deaths and $10 billion in damages. Unofficially, it is believed that the death toll is even higher and that the Myanmar government intentionally undercounted the dead to minimize the harm to its image and reputation. While we do not know for sure what happened, it is certainly the case that human factors can play a large role in the magnitude of disasters.

2005 Hurricane Katrina, US Gulf Coast

The 2005 Atlantic hurricane season was one for the record books. Katrina wasn’t even the most powerful storm that season. Both Hurricane Rita and Hurricane Wilma were more powerful; Wilma was the most powerful ever in the Atlantic. But Katrina is the one we remember most because it caused, by far, the most damage. Whereas Rita and Wilma passed through less populated areas, Katrina passed directly through one of the most populous and most vulnerable sections of the Gulf Coast, in particular, the city of New Orleans. About 1,800 people died. According to NOAA, damages totaled about $160 billion, making Katrina the most expensive natural disaster in United States history (Hurricane Harvey is second at around $130 billion). As the following video shows, however, the damages were due to human factors as well as natural factors.

Compared to Cyclone Nargis, Hurricane Katrina caused fewer deaths and cost much more in damages. This is largely because the United States is a wealthy country and Myanmar is a poor country. In general, disasters cause more deaths in poor countries and more dollars in damage in rich countries. The role of wealth in natural hazards will be discussed in more detail in the module. Finally, note that hurricanes and cyclones are different names for the same type of event. The word hurricane is used for the Atlantic. Typhoon is used for the Pacific, especially towards the Asian coast. Cyclone is used worldwide.

As the videos of Cyclone Nargis and Hurricane Katrina show, the exposure of populations to natural hazards, the existence of protective infrastructure, and the effectiveness of emergency response and reconstruction are largely human factors that influence the severity of disasters. In addition, uneven distribution of wealth, education, and services within an affected area makes some people more vulnerable than others. Furthermore, some meteorological and hydrological hazards are becoming more severe due to anthropogenic climate change. For these and other reasons, many geographers such as Neil Smith find the phrase “natural disaster” misleading, as if the disaster were only natural and therefore inevitable. In this course, we will use the phrase “natural disaster” simply as a widely accepted convention, with the understanding that human and political factors, in addition to natural conditions, all come into play in determining the severity and distribution of damage following a natural hazard. In the following sections of this module you will learn more about natural hazards and the human factors that influence their impacts.

"Hazard always arises from the interplay of social and biological and physical systems; disasters are generated as much or more by human actions as by physical events." (Geographer Gilbert F. White, the “father of floodplain management”)

A hazard is distinguished from an extreme event and a disaster. A natural hazard is an extreme event that occurs naturally and causes harm to humans – or to other things that we care about, though usually the focus is on humans (which, we might note, is anthropocentric). An extreme event is simply an unusual event; it does not necessarily cause harm. Note that many hazards have both natural and artificial components. Because hazards are threats of harm mainly to human systems, human activities play a large role in how severe a hazard is. For example, when large numbers of people crowd into floodplains and low-lying areas, they are putting themselves in harm’s way, increasing the severity of potential floods. Similarly, as we saw in the urban landscapes page of Module 7, many major cities are built in coastal areas. These cities face the threat of rising sea levels, a hazard being caused by global climate change, as discussed in Module 9. In short, the severity of the impacts from a natural hazard depends on both the physical nature of the extreme event and on the details of human development decisions.

What makes an event a disaster? This is in many ways an ethical question. A natural hazard escalates into a natural disaster when an extreme event caused harm in significant amounts and overwhelms the capability of people to cope and respond. Then what do we mean by "harm"? This is essentially asking what it is that we ultimately care about. The question of how we define "disaster" is similar to the question of how we define "development," as discussed in Module 5. As with "development," there are definitions of "disaster" that emphasize monetary measures and definitions that emphasize health measures. The severity of a disaster is commonly measured in terms of the dollars of damage it causes or in the number of deaths it causes. All else equal, a disaster that causes more dollars of damage will usually also cause more deaths.

However, this is not always the case. Disasters in poorer regions tend to cause more deaths; disasters in richer regions tend to cause more dollars in damages. This is because poorer regions tend to be less capable of protecting their populations and because richer regions tend to have higher-cost development exposed to the extreme event. We saw this on the previous page in comparing Hurricane Katrina (2005) to Cyclone Nargis (2008). Both were tropical cyclones of high intensity (Katrina's winds were 175 miles per hour; Nargis's were 105 mph) that hit heavily populated coastal regions, including major industrial cities (New Orleans, population 1.5 million; Yangon, population 4.4 million). But whereas Katrina caused about 2,000 deaths and $80 billion in damages, Nargis caused about 140,000 deaths and $10 billion in damages. This rich/poor difference between monetary and human life impacts is typical for disasters. The difference makes it important for us to pay attention to how "disaster" is defined.

Common Types of Natural Hazards

Natural hazards can be classified into several broad categories: geological hazards, hydrological hazards, meteorological hazards, and biological hazards.

Geological hazards are hazards driven by geological (i.e., Earth) processes, in particular, plate tectonics. This includes earthquakes and volcanic eruptions. In general, geological extreme events are beyond human influence, though humans have a large influence on the impacts of the events.

Meteorological hazards are hazards driven by meteorological (i.e., weather) processes, in particular those related to temperature and wind. This includes heat waves, cold waves, cyclones, hurricanes, and freezing rain. Cyclones are commonly called hurricanes in the Atlantic and typhoons in the Pacific Ocean.

Hydrological hazards are hazards driven by hydrological (i.e., water) processes. This includes floods, droughts, mudslides, and tsunamis. Floods and droughts can cause extensive damage to agriculture and are among the main contributors to famine. The deadliest natural disaster in world history (not counting pandemics) was the 1931 Central China floods, killing three or four million people.

Biological hazards are hazards driven by biological processes. This includes various types of disease, including infectious diseases that spread from person to person, threatening to infect large portions of the human population. Many discussions of natural hazards exclude biological hazards, placing them instead within the realm of medicine and public health. If biological hazards are counted, then they include the deadliest disasters in world history, including the Black Death outbreak of bubonic plague in the 1300s, killing 75-100 million people, and the 1918 "Spanish" flu pandemic, a global affair (the name "Spanish" is due to historical coincidence) killing 50-100 million people. A more recent example is the COVID-19 pandemic.  An understanding of geographic concepts has been integral for answering questions like where the virus is more prevalent, where it is more deadly, how fast it moves, and how do we prevent its spreading? It is also helps us to see that natural disasters are not always purely natural. Human actions have been important for both the spread and containment of the virus. While biological hazards are undoubtedly important, they are not discussed in detail in this module.

It is possible for an extreme event to fit within more than one of these categories. For example, volcano eruptions (a geological event) block incoming sunlight, potentially enough to cause cold waves (a meteorological event). This happened in dramatic fashion in 1816 when the Mount Tambora eruption caused the 'year without summer' in the Northern hemisphere. Volcano eruptions can also cause tsunamis (a hydrological event); some of the largest tsunamis ever occurred when volcanoes along coasts caused large landslides into the water. Earthquakes (a geological event) that occur under water can also trigger tsunamis (a hydrological event), such as the 2011 Japan Earthquake and Tsunami.

Systems of Hazards

One extreme event can often be hazardous in several ways. For instance, an earthquake may destroy buildings, cause landslides, and rupture sewer and water lines. The ruptured lines may, in turn, contaminate water, causing water-borne diseases such as cholera. Indeed, a cholera outbreak happened after the 2010 Haiti earthquake because of disruptions to clean water supplies.

Likewise, a single natural hazard can have many impacts. For instance, hurricanes involve high winds, torrential rain, flooding, and storm surges. The winds may remove roofs and topple power lines. The floods may inundate roads, homes and schools. Ecosystems can be damaged, threatening wildlife. Some impacts can even be beneficial. A hurricane churns up ocean water, cooling surface water and thus reducing the risk of another hurricane in the same area. Keeping track of these systems of hazards and impacts is an important part of the study of hazards.

Who Studies Natural Hazards?

Contemporary research on natural hazard is interdisciplinary. Natural scientists study the nature of the extreme events involved in hazards. Social scientists study the human dimensions of the impacts and responses. Policy researchers, engineers, and ethicists study what can and should be done to prepare for hazards and to respond to them when they occur. Some specific fields active in natural hazards research include geography, medicine and public health, psychology, economics, engineering, and sociology. Cartography and geographic information science are increasingly important because these fields help analyze important spatial information about hazards. Later in the module, we will see some examples of how cutting-edge information technology is being used to revolutionize disaster response.

Career Options

For better or worse, natural disasters occur frequently and cause much damage, creating the need for dedicated natural hazards professionals. Hazards professionals are employed in government, in private for-profit and non-profit organizations, and in universities and research institutes. People work in characterizing hazards, preparing communities for hazards, providing emergency services after disasters strike, helping communities rebuild, documenting disasters, and raising awareness. People work as project managers, database analysts, operations analysts, environmental experts, and psychiatric consultants. The largest U.S. government employer for disaster management is the Federal Emergency Management Agency (FEMA). Major international organizations involved in natural hazards include the United Nations World Food Programme and the United Nations Educational, Scientific and Cultural Organization (UNESCO). Major non-profit/non-governmental organizations include the Red Cross/Red Crescent organizations, Catholic Relief Services, Oxfam, and Mercy-Corps. Many people in these and other organizations focus exclusively on natural hazards projects. Others combine work on natural hazards with work on other issues, which is appropriate given how tightly connected natural hazards are to so many other issues.

The concept of vulnerability encompasses a variety of definitions. In general, vulnerability means the potential to be harmed. Vulnerability to natural hazards is thus the potential to be harmed by natural hazards. Some people and places are more vulnerable to certain hazards than other people and places. While any one extreme event may be unusual, there are broad trends in natural hazards. These trends are due to characteristics of both natural systems and human systems. By characterizing these trends, we can understand who and what is vulnerable and in what ways they are vulnerable. This, in turn, helps us reduce vulnerability and, when extreme events occur, reduce the damage. This work saves lives, and much more.

Disaster Trends Across Space & Over Time

The risk of specific natural hazards varies widely from region to region. For example, floods tend to occur in low-lying areas near water. The Sahel region (the southern edge of the Sahara desert in Africa) is periodically plagued by droughts. Forest fires tend to occur (as you might guess) in forests. Earthquakes and volcanoes tend to occur near boundaries of tectonic plates. Many of the world’s earthquakes and volcanoes occur along the edge of the Pacific Ocean, along the boundaries of the Pacific Plate. This region is known as the Ring of Fire for its intense volcanic activity.

Figure 8.1 The Ring of Fire: The Ring of Fire is a zone of many earthquakes and volcanoes.

Credit: U.S. Geological Survey, Department of the Interior/USGS (Public Domain)

Within the United States, some regions are more vulnerable to natural hazards than others. For example, Pennsylvania has a relatively low vulnerability, whereas Florida has a relatively high vulnerability. Pennsylvania gets a lot of hot weather in the summer, cold weather in the winter, and rainfall throughout, but while this all can be inconvenient or unpleasant, it is usually not dangerous. Florida, on the other hand, doesn't have to bundle up so much in the winter, but it does face frequent hurricanes.

Generally speaking, disasters are becoming less deadly but more costly. Fewer people are dying in disasters, but damages are costing more in dollars. Improved science and technology is a main reason that fewer lives are lost. We are now better at forecasting disasters, and our buildings and other structures can better withstand the physical impacts. This increases our resilience to hazards. Growth in population and the economy is a main reason that more money is lost. Simply put, society now has more of value that is exposed to hazards. Even though much of this is also more resistant to damage, the total dollar amount of damage has been increasing.

These trends can be seen in graphs available online from EM-DAT, the International Disaster Database. Using the EM-DAT query/ Mapping tool (note: you will need to register in order to access this tool), you can view the number of disasters, the number of people affected, and the dollars of damages from 1900 to 2021. Please adjust the settings to examine several graphs. You can see that deaths are declining while the number of people affected is increasing over time, mainly due to population growth. There is also an increase in the number of disasters reported, which can be caused by population growth, economic growth, or changes in reporting standards. It seems that natural disasters are getting more costly perhaps because people are building more expensive infrastructure in hazard-prone areas.

Human Factors

The severity of a disaster depends on both the physical nature of the extreme event and the social nature of the human populations affected by the event. Here are some important human factors that tend to influence disaster severity. A core point here is that different people, even within the same region, have different vulnerability to natural hazards.

Wealth. Wealth is one of the most important human factors in vulnerability. Wealth affects vulnerability in several ways. The poor are less able to afford housing and other infrastructure that can withstand extreme events. They are less able to purchase resources needed for disaster response and are less likely to have insurance policies that can contribute. They are also less likely to have access to medical care. Because of these and other factors, when disaster strikes, the poor are far more likely than the rich to be injured or killed. But there are exceptions. For example, some coastal areas contain expensive beachside real estate populated mainly by the rich, leaving the rich more vulnerable to tsunamis, storm surges, and other coastal hazards. Also, the rich tend to lose more money from disasters, simply because they have more valuable property at stake. We've already seen one example of the role of wealth, in the comparison of Hurricane Katrina (wealthier area, fewer deaths, higher monetary damage) to Cyclone Nargis (poorer area, more deaths, less monetary damage).

Education. Education is another important factor in hazard impacts. With education, we can learn how to avoid or reduce many impacts. When populations are literate, then written messages can be used to spread word about hazards in general or about specific disasters. Even without literacy, it is possible to educate a population about hazards in order to help it reduce its vulnerability. When populations include professionals trained in hazards, then these people can help the populations with their hazards preparations and responses. We'll see one example of the role of education on the next page: research by scholars in the Penn State Geography Department being used to help coastal communities in the face of hurricane storm surges. Here is another example that will help clarify exactly what sort of education is important for natural disasters.

Governance. The nature of both formal governments and informal governance in a population is another important factor. Governments can advance policies that reduce vulnerability. They can establish agencies tasked with reducing vulnerability, such as FEMA in the United States. They can support education and awareness efforts, as well as economic development to reduce poverty. Finally, they can foster social networks and empower individuals and communities to help themselves to prepare for and respond to hazards. Likewise, even without governments, communities can informally engage in many of these governance activities. Often the most vulnerable people are those who are politically marginalized because these people have less access to key resources and opportunities. One example of the role of government that we've seen already is the Myanmar government during Cyclone Nargis. This government is isolated from the international community and, thus, was not welcoming to international assistance in the aftermath of the cyclone. Compare that to Haiti after its 2010 earthquake. Haiti, like Myanmar, is a poor country, but it has positive and close relationships with the international community and thus readily welcomed international assistance in the aftermath of the earthquake. This assistance saved many lives and is helping Haiti rebuild.

Technology. The capabilities of the available technology can also play a large role in disasters. Technology can improve our ability to forecast extreme events, withstand the impacts of the events, and recover afterward. Technology is closely tied to wealth, education, and governance. Wealthier, more educated societies are more likely to have more advanced technology. A society's governance systems play a large role in how - and how effectively - the available technology is used in a disaster situation. One striking example of the role of technology is in the international response to the 2010 Haiti earthquake. On the next page, we'll learn about new Internet mapping technology such as Ushahidi that was used to help rescuers locate people in need. A lot of other technology was used in the response. For example, the U.S. Navy sent the USNS Comfort, a hospital ship, to treat the injured, and several helicopters to transport the injured to the ship. Helicopters were also used to distribute water. The helicopters were crucial because Port-au-Prince's port was damaged, as were many roads.

Figure 8.2 Striking Example of the Role of Technology: A Coast Guard HH-60 helicopter brings injured Haitians from a landing zone in Killick at the Haitian coast guard base to the USNS Comfort for medical treatment.

Credit: USCG Cutters Haiti 2010 Earth Quake by the US Coast Guard from Wikimedia (Public Domain)

Age. Children and the elderly tend to be more vulnerable. They have less physical strength to survive disasters and are often more susceptible to certain diseases. The elderly often also have declining vision and hearing. Children, especially young children, have less education. Finally, both children and the elderly have fewer financial resources and are frequently dependent on others for survival. In order for them to survive a disaster, it is necessary for both them and their caretakers to stay alive and stay together. An example of the role of age is the 2003 European heat wave. About 40,000 people died in one of the hottest summers ever in Europe. Many of the deaths were elderly people who were still capable of taking care of themselves. These people were not able to adapt to the extreme heat and had no one helping them out.

Disabilities. People with disabilities are particularly vulnerable to natural hazards. Some emergency response technologies do not meet the needs of people with disabilities. For example, radio communication is not effective for warning deaf people about an incoming wildfire or hurricane. People who cannot walk may not evacuate on time if they don’t have a car or if public transportation is not properly equipped with a ramp or lift. Moreover, during a disaster it is difficult for caretakers or family members to reach people with disabilities who need special assistance.

Vulnerabilities associated with social norms and discrimination. Social norms and discrimination based on sex, sexual orientation and race may place certain groups in a more vulnerable position than others. In places where men are raised to be breadwinners, families prioritize boys’ education over girls’, thereby making women more likely to be poor and less educated than men. Women often face additional burdens as caretakers of families. When disaster strikes, women are often the ones tasked with protecting children and the elderly. This leaves them less mobile and more likely to experience harm themselves. LGBTI people may face difficulties in shelters after a natural hazard strikes. Since the government usually sets up same-sex shelters, trans individuals are not easily assigned to the appropriate shelter because government officials expect their gender identity to match their sex as stated in their IDs. In addition, because many LGBTI individuals conceal their sexual identities in public to avoid harassment, loss of privacy due to the destruction of homes may result in additional stress. This happened in the aftermath of the Haiti earthquake. Histories of racial segregation and institutionalized discrimination in many countries have resulted in greater poverty rates and lower quality housing and services among people of color. However, these material disparities alone do not explain the greater losses experienced by people of color. Several studies show a racial bias in emergency response. For instance, after the Loma Prieta earthquake in 1989, the media covered damage in whiter areas earlier than in ethnic minority neighborhoods, leading to a quicker emergency response in the former. In addition, whiter neighborhoods received more volunteers than equally affected neighborhoods with more people of color.

Intersectional approaches to vulnerability. People’s personal experiences during disasters are uniquely conditioned by not one, but several intersecting identities. For example, a young white, low-income man with a disability and a low-income elderly woman of color living in the same neighborhood may both be very vulnerable to a hurricane, but their experiences of vulnerability will certainly be quite distinct. Importantly, these intersecting human factors of vulnerability cannot be simply “added”—they are compounded in complex ways that are difficult to predict, but are revealed during the disaster.

Are there other human factors that influence disaster severity? Can these factors be integrated into disaster preparedness so that people can be better prepared and have faster and more efficient response to disasters?

There are many steps we can take to prepare for natural hazards and to respond when extreme events occur. These steps can be divided into several categories, though it is important to note that there is no clear distinction between these categories.

Pre-event Preparedness

When an extreme event is projected to occur, steps can be taken to make the event less of a disaster, i.e., to reduce the amount of harm that occurs. A key part of preparedness is in the projection itself. The more we know ahead of time about the event, and the further ahead of time we know it, the more effectively we can prepare for it. With prior warning, we can develop and implement plans to reduce harm. Note that it is not enough to have information about the upcoming event: the information must be communicated effectively so that the information is put to use. Given the information, there are several steps that can be taken. Some people can leave the affected area to avoid harm. Those who remain can make other preparations. Finally, those involved in disaster recovery efforts can make plans for their response.

Pre-event preparedness can be seen in preparations made in advance of Hurricane Katrina in 2005. Meteorologists forecasted the hurricane several days in advance. The director of the National Hurricane Center contacted the Mayor of New Orleans, the President of the United States, and others, expressing grave concern. This prompted a series of preparations. Evacuations were ordered; hundreds of thousands of people left the New Orleans area alone prior to the storm. Highways were set so that all lanes moved in the same direction: away. Those who remained made other preparations, such as those who gathered in the Louisiana Superdome for shelter. The Superdome was chosen in part because it was so large (about 26,000 people took shelter there) and in part because it was one of the few places in town situated above sea level, as can be seen from this photo:

Figure 8.3 Aerial view of the city of New Orleans: The Superdome building is in the center and the rest of the city is flooded.

Credit: Navy-Flooded New Orleans by the US Navy from Wikipedia (Public Domain)

In addition to people evacuating and taking shelter, various public and private organizations planned for the subsequent emergency response. It should be noted that many people have criticized the pre-Katrina preparations as inadequate. But some preparations were made. Without these preparations, the damages would have been much more severe.

Emergency Response

Immediately after an extreme event occurs, emergency response seeks to reduce harm. A core goal of emergency response is to help affected people survive: pulling people out from under the rubble, attending to major injuries, distributing food and water, and building shelter. Here, people draw on whatever resources they can to keep people alive and in comfort. In major disasters, the international community will draw on its resources to deliver aid however possible. But emergency response also involves getting critical infrastructure back up and running as fast as possible. This infrastructure includes fuel and electricity, transportation routes, telecommunication systems, and clean water supplies. Indeed, an important part of the emergency response is quickly evaluating the scope and severity of the event and, in turn, what the key needs are.

Emergency response raises profound ethical questions. Imagine yourself standing in a disaster zone. Death and destruction are all around. What do you do? Who or what do you help? How would you decide what to do? For medical professionals, the situation is called triage: far more medical emergencies than can be addressed. One might neglect someone with “just a broken arm” in order to attend to someone who would otherwise die. Triage is a major use of ends ethics: the goal is to achieve the ends of the most lives saved.

Post-event Recovery and Reconstruction (Video- 4:20 minutes)

As the immediate emergency situation settles, focus shifts to the longer-term project of trying to get conditions back to normal, or at least as close to normal as can be achieved. As the most dire medical emergencies have been attended to (including cases in which patients die), treatment emphasizes bringing people back to full health. Buildings, roads, and other infrastructure are rebuilt and repaired. Basic needs are covered less and less from emergency stockpiles and outside aid and more and more from normal economic activity. The challenge of reconstruction can be seen vividly in the case of the 2010 Haiti earthquake. The earthquake killed over 300,000 people and destroyed many buildings. Five years later, conditions still had not returned to normal. Details of the situation can be seen in the following video produced by United Nations.

Recovery and reconstruction in Haiti face major challenges, not least of which is the threat of additional disasters. Haiti is in a major hurricane zone. In 2004, 3,000 Haitians died from Hurricane Jeanne. Furthermore, some seismological evidence suggests that the 2010 earthquake relieved only some of the pressure building up in the tectonic plates. In August 2021, another major earthquake hit Haiti, causing at least 2,200 deaths. These frequent extreme events make Haiti's long-term recovery much more difficult: just as it starts to get back on its feet, it gets knocked down again. This is one reason why Haiti remains the poorest country in the Western hemisphere.

Building Resilience in Non-disaster Times

Even when there are no specific extreme events that could happen anytime soon, there are steps that we can take to increase our resilience. These are generally long-term projects to enhance our physical infrastructure, our awareness, and other steps that will be useful to have in place when an event does occur. For instance, we can develop and enforce building codes requiring that buildings be able to withstand earthquakes or high winds. We can stockpile certain supplies to be available in times of need. We can develop insurance schemes to help each other recover from damages that occur. We can design and install warning systems to alert us to extreme events that may be about to occur. And we can study natural hazards so that we know how to prepare for and respond to them when an extreme event occurs.

Increasing resilience to natural hazards often requires a detailed understanding of the hazards. In the Penn State Department of Geography, several researchers are active in improving our understanding of hazards and in helping communities use this understanding to reduce their vulnerability and increase their resilience. Emeritus Professor Brent Yarnal studies the vulnerability of coastal communities to storm surges from hurricanes. Hurricane storm surge is an increasingly important issue because, as we will see in Module 9, climate change is causing sea levels to rise, making storm surges more severe. Professor Yarnal and his colleagues work directly with members of coastal communities, both to learn from their experience and to share research insights with them so that they can be better prepared for future hurricanes. This community engagement is seen in the photo below, showing community members in Sarasota County, Florida, planning land use so as to reduce vulnerability to hurricane storm surge. Note their use of maps to visualize the vulnerability of specific places! In general, university researchers and community members bring different perspectives and different resources to the table. By working together, we are able to better prepare for natural hazards.

Figure 8.4 Community Engagement to Increase Resilience

Credit: Brent Yarnel © Penn State University is licensed under CC BY-NC-SA 4.0

We study natural hazards because they are interesting and important, but also because we hope to reduce the damages caused by extreme natural events. Damage and losses from natural hazards are a major obstacle to sustainable development. In some sense, a community that can buffer the impacts of natural hazards is sustainable. Human populations always face natural hazards. When the impacts of an extreme event overpower a population’s abilities to cope (i.e., its resilience), there can be many significant losses, including loss of life, property, infrastructure (buildings, roads, etc.), and business. Sometimes these losses are so severe as to exceed the human system’s resilience and send it into a completely different state. For example, after Hurricane Katrina, many people moved out of New Orleans, never to return.

The natural hazards that we’ve discussed in this module have been mostly at local or regional scales. For example, the 2010 Haiti earthquake caused destruction mainly within one region of Haiti, which is a small country with about the same land area as Maryland. The response to the earthquake was global, but the disaster itself was not. The 2004 Indian Ocean tsunami caused destruction over a broader region, including parts of over ten countries. But neither these disasters nor any of the others discussed in the module were global in scale. Why, then, are natural hazards studied in a unit on global environmental change?

Perhaps the most important reason to study natural hazards in the context of global environmental change is to develop an appreciation for the subtle and specific ways in which humans prepare for and respond to environmental change in general. Natural hazards involve some of the most dramatic environmental changes at any scale and thus offer us important case studies for human-environment interaction. As we have seen throughout this module, extreme events challenge humanity to respond to environmental change, often by taking measures (such as medical triage) that we are usually uncomfortable doing. In many cases, if we do not try to respond, then people die, and often in large numbers. Such is the same with environmental change in general, including with global environmental change. As the environment changes, for any reason and at any spatial or temporal scale, we face the task of responding. The scenarios may not be as dramatic as the extreme events discussed in this module, but they are every bit as threatening.

Another important reason to study natural hazards in the context of global environmental change is that some natural hazards actually are of global scale. One is the hazard of objects from outer space: asteroids and comets. The largest of these can cause massive global destruction. Indeed, an asteroid impact is believed to have caused a global extinction event about 65 million years ago. The risk is sufficient enough that NASA maintains an active impact hazard monitoring program. Another global-scale hazard is the supervolcano: a massive volcanic eruption thousands of times larger than typical eruptions. Such an eruption would darken the skies for years, threatening the survival of many species, including humans. Fortunately, large asteroid and comet impacts and supervolcano eruptions are very rare and thus unlikely to happen anytime soon. But they could happen. Given the stakes involved, they may be worth at least some of our attention.

Finally, for any discussion of environmental change, it is important to remember the scales at which we as humans experience the environment. No matter how broad-scale an extreme event may be, we only experience it within our own portion of the world: our field of vision, our range of hearing, the local places that we exist in. For people in Indonesia that were hit by the 2004 Indian Ocean tsunami, on some level it did not matter that the tsunami also hit India, Somalia, and other far-off places. Their experience of the tsunami was immediate and local, as were the experiences of people in India, Somalia, and the other affected countries.

As we turn our attention to more global-scale processes, in particular, global climate change, it is important to remember that we experience these processes at the local scales of our lives. This holds for both the ways in which we help cause these global processes and the ways in which we are impacted by them. For this reason, we should keep in mind that global change is commonly experienced and addressed at local scales. Indeed, it is for this reason that the Association of American Geographers (AAG) led a team of leading geography researchers to write a book Global Change and Local Places. The ideas behind this book are central to the final set of modules and further illustrate the value of studying natural hazards in the context of global environmental change.

With that in mind, we will turn to one of the biggest examples of global environmental change - climate change - in our next module.

A natural hazard is an extreme event that causes harm to humans or to other things that we care about. Natural hazards include earthquakes, cyclones, tsunamis, floods, droughts, and many other types of events. Vulnerability to specific natural hazards varies across space and also within a place, based on factors such as age, gender, education, and so on. There are several steps that we can take to reduce our vulnerability to natural hazards, including increasing our overall resilience to them, preparing for specific extreme events, and responding and rebuilding after the event occurs. Researchers and professionals across several fields including geography have careers dedicated to reducing vulnerability to natural hazards and reducing the harm caused by specific extreme events. Community members also play important roles in reducing vulnerability and harm. While discussions of natural hazards often focus on events that occur at local and regional scales, there are global-scale hazards. There is also much to be learned from studying natural hazards (and, in particular, the human role in natural hazards) that can be applied to other topics in global environmental change.