4.2. Human Impact

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 have; 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 refers to how quickly a disaster occurs after it has been triggered. Different disasters have different speeds of onset. For example, a flash flood happens very suddenly without warning; it can occur in minutes. In contrast, cyclones have a slower onset. They can be predicted well in advance, allowing people time to prepare and evacuate if necessary. Earthquakes, like flash floods, occur suddenly and with little to no warning. Understanding the speed of onset helps in disaster risk management and preparedness. Knowing how much time you have can mean the difference between safety and disaster.

Think of a flash flood like a surprise pop quiz in school – it happens without any warning, and you need to be ready at a moment’s notice. On the other hand, preparing for a cyclone is like studying for an exam that you know is coming and can schedule your study time for. This preparation can help you stay safe during a cyclone.

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 happen and this happens, we can see that these plates come in contact with each other and the pressure builds up an earthquake occurs.

Earthquakes are often caused by movements along tectonic plate boundaries. The Earth's crust is made up of several large and small plates that can shift and move. When these plates collide, separate, or slide past each other, they can create pressure. Eventually, this pressure causes the ground to shake, which is what we experience as an earthquake. This process is crucial for understanding where and why earthquakes occur, and it helps scientists predict potential earthquake zones.

Imagine you are pushing two friends standing close together – as you push harder, they start to feel the pressure. Finally, they might push back or separate suddenly, creating a big mess. The friends represent tectonic plates, and the sudden movement represents an earthquake.

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 subductions; there is when one oceanic plate goes under the land plate and created the 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.

Three main processes can trigger earthquakes along tectonic plate boundaries: 1) Convergent boundaries, where two plates collide, can create mountains and earthquakes (like the Himalayas). 2) Subduction zones, where one plate slides beneath another, often lead to earthquakes in oceanic regions. 3) Divergent boundaries occur when plates move apart, creating earthquakes as new crust forms. Understanding these processes is essential for predicting where earthquakes are likely to happen and preparing for them.

Think of these processes like different ways to build a sand castle: you can push two piles of sand together (convergent), scoop out one pile to make room for another (subduction), or spread the sand out to create a wider castle (divergent). Each method has its 'shake' effect, similar to how the earth shakes during different types of earthquakes.

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.

Natural hazards such as earthquakes, floods, and storms have always existed and will continue to exist. It is impossible to completely avoid these hazards. Instead, the focus should be on managing the risks associated with these hazards and preparing communities to respond effectively. Understanding this concept helps shift our approach from avoidance to preparedness and resilience.

Trying to avoid natural hazards completely is like trying to avoid rain in a tropical climate – it’s simply not possible. Instead, you learn to carry an umbrella or wear rain boots. Similarly, communities should learn to prepare and respond to natural hazards just like they would for a rainstorm.

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 were the most common disasters reported, making up 35% of all disasters. Other significant types included wind storms, with earthquakes and extreme temperatures at 11%. This data shows that a large majority (90%) of disasters are related to water and weather, known as hydro-meteorological disasters. Recognizing the prevalence of these types informs how we prepare for and manage disasters.

It’s like a classroom full of students where a majority are raising their hands to discuss water-related issues – floods and storms – while only a few are interested in talking about things like earthquakes. This emphasizes that most disasters we face are connected to weather patterns.

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%, here is the regional distribution of natural disasters from 1980 to 2005.

From 1980 to 2005, nearly 70% of human deaths resulting from disasters were linked to hydro-meteorological factors, highlighting their severity, especially in underdeveloped countries. Droughts caused 28% of these losses, while floods and earthquakes contributed to 9% and 14%, respectively. This underscores the necessity of focusing on hydro-meteorological risks to improve disaster management strategies and save lives.

Picture a lifeguard at a beach. The lifeguard knows that most rescue situations arise from strong waves (related to hydro-meteorological conditions) rather than from other dangers. By prioritizing the management of strong waves, the lifeguard can save more lives, similar to how understanding the causes of human loss can help disaster response efforts.

You can see that Asia is one of the biggest sources 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 the all disasters and disaster impacts.

Asia is recognized as one of the regions most affected by disasters. Many disasters, particularly hydro-meteorological events like floods and droughts, are frequent here. This leads to a significant impact on the population and infrastructure. Acknowledging this helps governments and organizations target disaster readiness and response measures where they are most needed.

Imagine a garden that faces heavy rains and droughts frequently. A gardener would need to focus heavily on preparing for floods and managing water scarcity. Similarly, recognizing Asia's vulnerability allows disaster planners to focus their resources where they can help the most.

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 number of reported disasters increased across all continents, especially in Asia. This increase means more people faced losses and damages to property. Understanding this trend is essential for recognizing that climate change and human activities may contribute to the rising frequency of disasters, and it calls for better disaster preparedness and response strategies.

Consider a local sports team that keeps losing more games over the years. The coach realizes they need to change their training strategies and better prepare to compete. Similarly, as the number of disasters grows, societies must adapt and enhance disaster readiness.

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