1. Disaster Risk

In this lecture, we will talk about disaster risk considering 3 components; one is hazard, exposure, and vulnerability. so, we will give some small examples; illustrations with some theoretical ideas to define the very core aspect of disaster risk.

Disaster risk is defined by three components: hazard, exposure, and vulnerability. A hazard refers to a potential threat or event that can cause harm, such as natural disasters like earthquakes or floods. Exposure is the degree to which people or assets are exposed to these hazards. Vulnerability is a measure of how susceptible these exposed populations or assets are to the harm caused by the hazard. This framework helps in understanding the overall risk associated with disasters.

Consider a coastal city prone to hurricanes. The hurricane is the hazard, the coastal population and buildings are the exposure, and the poor construction quality of the homes makes them vulnerable. In this scenario, all three components interact to determine the overall disaster risk.

Let us imagine that this is a place near Roorkee in Uttarakhand; it could be a tourist spot, people coming here watching this mystic stone in a mountain well now, considering this slide is it risky? Does it look like that this could be fatal for the people, should you consider this is as disaster or disaster risk?

This scenario engages students to think critically about what constitutes a risk. By visualizing a stone in the mountains, students are prompted to consider the conditions under which it may become dangerous. Factors such as human presence and the likelihood of the stone falling illustrate that risk is context-dependent.

Imagine visiting a scenic viewpoint where a large rock is precariously balanced. If you're the only person there, it appears risky if the rock were to fall. However, if it is a busy tourist spot with numerous visitors, the risk becomes more pronounced due to numerous people being potentially harmed.

Now, look at the next slide, so if there is a rain then, there is a possibility that this stone would hit this person so yes, we consider this is as risky.

The introduction of rain changes the scenario significantly. Rain increases the risk of the stone falling, thereby heightening the danger for individuals near it. This situation underscores the importance of environmental conditions when assessing disaster risk.

Think of a stormy day and the risk of trees falling. If you see a tree that looks healthy on a sunny day, it seems safe. But during a storm, with strong winds and rain, it becomes a potential hazard, especially if you are standing too close.

But if it is like that maybe in a mountain when there is no human being and this stone falling down on a forest, do you consider it as risky; a disaster?

When considering risk in a remote area with no human presence, the perception of danger changes. A falling stone may not pose a risk to human life but could disrupt wildlife or natural ecosystems. This illustrates that risk is not solely about human safety; it also extends to the environment.

Imagine a rockslide in a remote area of the Himalayas. While no humans are affected, the landslide could have serious implications for wildlife habitats and the balance of the ecosystem, showing that disaster risk encompasses more than just direct human impact.

If we have avalanches, landslides in Himalayas, do we consider these events as disasters? But maybe if it is not in a remote mountain but people are living there, settlements are there compared to that top one, if we consider the bottom one to us, it is more risky than the top one.

The consideration of human settlements significantly affects the assessment of disaster risk. Avalanches or landslides in populated areas pose a greater risk than similar events in uninhabited regions, as they can directly threaten lives and property.

Think about an avalanche occurring in a remote valley compared to one that strikes a ski resort. The resort's visitors and staff are at immediate risk, while the avalanche in the valley could go unnoticed, illustrating the impact of human presence on disaster assessment.

If this is happening; this landslide at night time. And if this landslide is happening at day time, we have different concerns and different way of measuring risk. So, we considered that night time may be more risky because people are sleeping there.

The time of day significantly affects risk assessment. A landslide occurring at night poses a higher risk because people are asleep and may not be able to respond quickly to the threat. This highlights how human behavior and routines are critical to understanding disaster risk.

Consider an earthquake: if it happens during the day when people are active and alert, they may have the chance to evacuate. However, if it strikes at night, many may be asleep and unprepared, increasing the likelihood of injury or worse.

But if this same thing is happening in an urban place in a city area what happens?

Urban areas have distinct risk dynamics due to higher population density and infrastructure. The consequences of a disaster may be magnified in cities because many people are in close proximity to each other and to buildings that may not withstand certain hazards.

In cities, a single building collapse due to an earthquake can affect dozens of homes and thousands of people. In contrast, a similar event in a rural area might only impact a few homes. This illustrates how the setting can deepen risks associated with disasters.

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