1.2. Understanding Human Impact and Hazard Potential

So, also here is another chart you can see from 1950 to 2005, the number of events that flood is increasing, storm also are increasing, earthquake is almost the same as from 1950’s to 2005, you cannot see much huge differences but other disasters you can see they are increasing very prominently.

This chunk discusses the rise in the frequency of natural disasters such as floods and storms from 1950 to 2005. While the occurrence of earthquakes has remained relatively stable, other types of hazards show a significant upward trend. This increase can indicate an escalating impact on humans and their environments.

Imagine a city that has annual festivals. Over the years, attendance starts to grow significantly while some events remain constant in size. Similarly, while storms and floods become more frequent, earthquakes remain stable, suggesting that some disasters are becoming more common and possibly more severe.

So, we are talking about hazards that this landslide or this stone when it is exposed to heavy rainfall or earthquake, it can have some potentiality to cause human injury or loss or property damage. It may cause, not necessarily that it will cause.

This chunk explains that hazards are not guaranteed to cause harm, but they have the potential to do so. For example, a landslide may occur if heavy rain saturates the soil, which can lead to injuries or property damage in populated areas. The distinction here is understanding 'potentiality' versus certainty of harm.

Think of a car parked on the edge of a cliff during a rainstorm. There’s a potential for the car to slide off the edge if it rains heavily, just as there’s potential for landslides during heavy rainfall. The key takeaway is that while we're mindful of hazards, we must acknowledge that not every event results in damage.

When there is a landslide in Mumbai, landslide in Delhi we are concerned about but when there is a landslide in Himalaya, we are not concerned about this, when there is an earthquake in deep sea, we are not very much concerned unless and until the tsunami is coming on the mainland.

This chunk addresses a crucial aspect of disaster risk management—why some hazards are more concerning than others. The response to hazards often depends on geographic location and human presence. Events in populated areas draw more attention and concern compared to those in remote or less populated regions.

Consider a celebrity living in a city versus one living in a remote area. If something happens to the celebrity in the city, media attention and public concern grow significantly compared to the remote celebrity. Similarly, human impact drives concern regarding a hazard.

The situation of people, infrastructure, housing, production capacities and other tangible human assets located in hazard-prone areas.

Here, 'exposure' refers to the vulnerability of people, properties, and infrastructure within hazard-prone zones. The more assets and people that exist in these high-risk areas, the greater the risk of impact from natural disasters.

Imagine a community built on a riverbank. If a flood occurs, the community faces greater damage, showing how exposure to hazards can amplify risk concerning human assets in the area.

Another one is the quantity; how many people or structure or buildings are exposed to the hazard, another one is the amount and type of activities they support.

In this chunk, we learn about the metrics used to assess exposure. Not only the number of people and buildings matter, but also the types of activities those structures support. Different activities, such as industrial versus agricultural, can influence how risk is calculated.

Think about a factory compared to a farm. If a flood threatens a factory, the economic loss from halted production can be significant, whereas the same flood might have a smaller impact on a farm. Statistical approaches assess risk by considering these activities within the buildings.

It also matter that if this hazard would take place at day time, when people are not working, people are working outside, people are not at their home.

Time of occurrence plays a vital role in risk exposure. Hazards may be more impactful depending on whether they occur when people are likely to be at home or away. During the night, when people are mostly at home, the risk is often higher than during the day.

Consider a fire breaking out in a building during the night when everyone is asleep versus during the day when many people might be outside. This temporal factor significantly alters the potential human impact.

If a community is comprised by only old people, no young people, then we consider that this community is at risk than a community which has more younger population.

This chunk highlights that the characteristics of a population influence risk assessment. Older populations may be more vulnerable during disasters due to mobility issues, hence such communities are regarded as at higher risk compared to younger, more active populations.

Imagine a community built mostly of elderly residents during an evacuation order. They may struggle to evacuate quickly compared to a community of young individuals who could move swiftly, affecting overall risk levels.

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