Geographical hazard is a very important topic that should be given great consideration because it involves the safety of our lives, our habitats, our possessions, and future generations.
There are lots of natural hazards that occur in our environment, which can be divided into the following categories:
- Biological hazards
- Geographical hazards
- Hydrological hazards
- Meteorological hazards
However, in this module, we will only address the concept of a geographical hazard because it directly relates to our field of study. We hope to make you fully aware of what these hazards can do to humanity and what we can all do to minimize casualties and damage to our environment. Here is an overview of the topics that we will tackle in this discussion:
- The definition of geographical hazard and how it can affect humans and our environment.
- The different kinds of geographical hazard that we experience in our environment.
- How to minimize casualties and negative effects in our environment.
To get started, what is a geographical hazard? As a subcategory of the natural hazards that our planet presents, a geographical hazard is also known as a geological hazard because it involves processes related to the earth, such as volcanic eruptions, earthquakes, avalanches, wildfires, landslides, mudflows, ice jams, lahar flows, ash flows, tsunamis (when triggered by an earthquake), and more.
These hazards can all cause damage or loss to the following:
- Human activity
- The environment
The hazards’ effect on humans, human activity, assets, and the environment can be mild or severe depending on the type of disaster and its strength. Let’s consider as an example an earthquake.
The damage that an earthquake can cause depends on the intensity, but also other factors like the surroundings. For instance, damage can be intensified in a place that has large buildings with substandard foundations. These substandard buildings will tremble and likely fall if a strong earthquake hits. This can result in the loss of lives and harm to animals and properties, as well as other unpredictable problems.
What is a Hazard Event?
A hazard event only occurs when a certain calamity causes destruction. An environmental event only turns into a hazard once it threatens the people and environment of a certain area. There are many natural events that do not cause any direct harm to human lives. For example, some volcanic eruptions are not very severe and occur within a safe zone. An eruption only becomes hazardous once people enter within the reach of the volcano.
However, it should be clarified that even if an event does not pose a direct threat to human lives, it can still have consequences:
- Ash and lahar flow from an active volcano’s eruption can trigger certain conditions like asthma and pulmonary diseases in humans and animals.
- The ash that erupts from a volcano often contains materials that can rust or damage the roofs of houses.
- Toxic contents within ash and lahar flows can be transferred to the soil and damage plant life.
Level of Harm Factors
There are two important factors when it comes to determining the impact that a natural event can have on a certain region. Those determinants are:
- The hazard’s magnitude – one of the most important factors for estimating the number of casualties, if any. It can give an idea of how bad the aftermath will be for affected infrastructures. Consider, for example, the measurement of the strength of an earthquake.
- The hazard’s frequency – another very important factor, this determines how many times a disaster will happen. Using the example of an earthquake, again, knowing the frequency of the event plays an important part in determining the aftermath that a specific earthquake may bring. Most earthquakes are not singular events and can strike one after another, though we cannot know when another will strike.
That is why it is so important to consider frequency when studying geographical hazards, because high frequency, low-intensity earthquakes can be just as disastrous as a one-time, high-intensity earthquake.
What are the classifications of hazards?
In order for you to understand the concept of hazard in a geographical context, you must know how to differentiate it from other classifications of hazard. There are several ways of classifying hazards to determine if it is a natural or artificial event. Here are the three classifications of hazards:
- Natural hazards – these are processes that are caused by nature in a particular environment with no artificial methods involved that can put people’s lives and property at risk.
There are two main types of natural hazard namely:
- Slow onset: this type of disaster takes months or years to unfold.
- Sudden onset: this type of disaster is abrupt and can generally be predicted, such as earthquakes, hurricanes, and other common disasters.
- Quasi-natural hazards – these are events where a benign natural state or process is made worse by the activities of humans.
- Man-made hazards – these are hazards that are the result of human activities. Two examples are chemical spills and radiation leakage.
Now you know the different classifications of hazard and have a deeper understanding of the topic of geographical hazards.
Why Disaster Management is So Important
Disaster management provides guidelines to be implemented to minimize the damaging effects that a natural hazard can bring to a region. By using the knowledge and resources that disaster management disseminates to people, you can prepare ahead of time before a disaster strikes.
To conclude, natural geographical disasters put the lives and properties of people in danger. However, with disaster management, the effects can be significantly reduced.