4.1. Disaster Types

Now, coming another important feature is the speed of onset like, if we consider a flood, it is a flash flood, it is very sudden without warning, very quick or is it a kind of slow process like in case of cyclone, we have much time to predict so, we can prepare our self, we have better early warning system and we can take time but in case of earthquake, we do not have any time, it is very sudden or in case of flash flood, we have less time also consider to other kind of a flood.

The speed of onset of a disaster refers to how quickly a disaster strikes and how much warning individuals have before it occurs. For example, a flash flood can happen suddenly with little to no warning, making it challenging for people to prepare. In contrast, events like cyclones provide more advance warning, allowing for better preparedness. Earthquakes, however, are unpredictable and occur abruptly, giving no time for preparation.

Imagine planning a picnic. If a sudden rainstorm hits unexpectedly, there's little you can do to protect yourself or your picnic. This is like a flash flood. Alternatively, if a weather report indicates a storm is coming in a few days, you have time to reschedule your picnic or bring an umbrella, like with a cyclone warning. Earthquakes are like a surprise thunderclap; you have no warning and must react immediately.

In case of just for an example, maybe we can see that in case of earthquake; earthquake occurs along the boundaries of the tectonic plates of the earth crust. This is one hazard and when this is the source of the hazards and when this happens, we can see that these plates come in contact with each other and the pressure builds up an earthquake occurs.

Earthquakes are caused by the movement of tectonic plates, which are large sections of the Earth's crust. These plates can collide, pull apart, or slide against each other. When they press against one another, stress builds up until the rocks break or shift, resulting in an earthquake. Understanding this movement is crucial for predicting where earthquakes might occur.

Think of a rubber band. When you pull it, tension builds until it snaps. This is similar to what happens with tectonic plates; the 'snap' is the earthquake when the pressure is released.

Now, this is just simply a physical event, this is you can see some of the distribution of the tectonic plates in some places and this hazard; this earthquake hazard, we have 3 processes; physical process that can trigger this hazard. One is that convergent boundaries; when two plates collide together this created the Himalayan mountain so, one way of the event of earthquake that can happen when two plates are colliding each other. Another was is the subduction; there is when one oceanic plate goes under the land plate and created this kind of earthquake. And another one is the divergent one, when two plates are moving apart, this can also cause earthquake. And this is we call divergent region.

There are three types of tectonic plate boundaries that can lead to earthquakes: 1) Convergent boundaries, where two plates collide; this can sometimes create mountains like the Himalayas. 2) Subduction zones, where one plate moves under another, often leading to powerful earthquakes. 3) Divergent boundaries, where plates move apart, allowing magma to rise and create new crust, which can also cause seismic activity.

Imagine two cars colliding at an intersection; they can crumple upon impact like converging plates. Conversely, think of two trains moving away from each other on parallel tracks; this represents divergent boundaries.

Now when we are talking about hazards, can we avoid hazard? No, historically hazards were there, it is there and it will remain. So, we cannot avoid hazard basically.

Hazards are natural events that cannot be avoided. They have always been a part of Earth's environment and will continue to exist. While we cannot prevent hazards from occurring, we can prepare for them and aim to reduce their impact on people and communities.

It's like living near a volcano; you can't stop the volcano from erupting, but with appropriate preparedness, like evacuation plans and safety drills, you can protect yourself and your family.

Now, looking into the disaster; number of disasters from 1980’s to 2005, you can look as I told also before, it is the flood that is the most reported disastrous event. 35% of the all disasters are from 1980 to 2005 are flood disasters. Another one is also big share is the wind storm, earthquake is only 11%, an extreme temperature is 11%, so overall 90% of disasters are related to hydro-meteorological disasters, that is very important finding.

From 1980 to 2005, floods emerged as the most common disasters reported, comprising 35% of total disasters. Wind storms also contributed significantly, while earthquakes and extreme temperatures were less common, each comprising only 11%. This highlights the prevalence of hydro-meteorological disasters, which account for 90% of reported disasters during this period.

Think of disaster events as a pie chart; the largest slice is for floods, showing how common they are compared to smaller slices for earthquakes and extreme temperatures. This helps visualize priorities for disaster readiness.

Also, when we are looking into the loss of human life from 1980 to 2005, we can see that nearly 70% of loss of life are related to hydro-meteorological factors. So, hydro-meteorological disasters are very critical, particularly when we are looking into developing countries or underdeveloped countries. Here you can see that 28%, drought is the reason of human loss in 28%. Similarly, flood 9%, earthquake is only 14%...

Between 1980 and 2005, hydro-meteorological disasters accounted for nearly 70% of all deaths linked to disasters, indicating their critical impact, especially in developing countries. Droughts alone were responsible for 28% of these deaths, while floods and earthquakes contributed significantly less at 9% and 14%, respectively.

Consider a country that faces a drought. It’s like a garden lacking water; plants (or people) cannot thrive and may wither. This starkly shows how connected environmental factors are to human life and safety.

Similarly, flood 9%, earthquake is only 14%, here is the regional distribution of natural disasters from 1980 to 2005. You can see that Asia is one of the biggest source of disaster, it is one of the hotspot compared to any other region, when we are talking about disasters. And it is the hydro-meteorological particularly, the flood and drought which play a big share of all disasters and disaster impacts.

Asia has been identified as a major hotspot for disasters from 1980 to 2005. The region experiences a high frequency of hydro-meteorological disasters, especially floods and droughts, making it heavily impacted by these events compared to other parts of the world.

Think of Asia as a stormy ocean, with floods and droughts like waves crashing again and again, highlighting the continuous nature of challenges the region faces.

Here is also you can see from 1991 to 2002, the growth of disasters. So, actually it is increasing in all continents particularly in Asia, so in 1990’s and 2002, you can see in Asia’s, these disasters are actually more and more reported and more and more human losses and property damage are reported.

From 1991 to 2002, the frequency of reported disasters increased across all continents, particularly in Asia. This rise in reports correlates with higher casualty figures and property damage, signifying a growing concern for disaster management in this region.

Picture a busy city street; the more cars on the road, the higher the chance of an accident. Similarly, as more disasters are reported, the need for effective responses and preparations continuity grows larger.

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