Natural Disasters by Nicholas Phung-Zhang 4L

The environmental topic that I would be addressing today is natural disasters.

1.The first photo depicts a Volcano that has just erupted by shooting lava out of the cone, which contains thick black ashes and ‘red’ gas.

A Volcano is an opening in the earth’s crust, often in the shape of a conical mountain, through which lava, gas and ash sometimes burst out.

The magma within the largely solid mantle sometimes rises and collects in certain places. When there is too much magma in the chamber, the pressure of the subsurface of magma exceeds the pressure of the overlying rock. The magma is buoyed by water vapor and other hot gases, then the magma migrate through cracks and vents towards surface. Then the volcanoes are formed when it rises to the earth’s surface and bursts out.

There are many kinds of volcano eruptions, most form along plate boundaries or under the sea. Volcanoes that erupt regularly are known as active volcanoes, e.g. Mount Kilauea. The ones will never erupt again are called extinct. Those are in sleeping stage are known as dormant.


2.The second photo shows that aftermath of an earthquake, the house has been nearly destroyed and the left part of the building has caused the ground beneath it to subside.

The constant movement of plates causes pressure to build up at faults, and at the plate boundaries themselves. When two plates move apart or push upward, or slide against each other, an earthquake occurs.

When the pressure produced by these movements reaches a certain level, the pent-up energy ruptures the rocks and creates a fracture known as a fault. This sudden release of energy also unleashes the ground-shaking vibrations that constitute an earthquake.



3.The third picture I chose is that a terrified child is holding tightly on his relative or a rescued person, the water level has reached to the man’s chest. The devastating situation is because of flooding.

Flooding is great overflow of water, which can be caused by natural such as high rainfall, snowmelt or sudden relief water in the low land and can be caused by other natural disasters. Another reason of flooding is caused by human, for instance, deforestation, poor farming, overgrazing and over cultivation, plus poor water management and the population pressure. Flooding can be very devastating if the water rises like the picture shown.


4.The fourth picture describes the huge fire is burning in the forest. Forest fires can be caused by forces of nature or human negligence.

Fire needs fuel, oxygen and heat to survive. In the forest, the fuel is provided by trees and brushes. When it is in the hot and dry summer, the wood is extremely dry (when wood reaches 572°F, it gives off a gas which reacts with oxygen to make a flame. The flame will heat the remaining wood, making the fire grow stronger.) Lighting, campfire sparks, flint or matches can help wood reach the flash point necessary to create a fire.

5.The last photo I want to highlight is hurricanes. Hurricanes are the most dangerous storms on the earth, it starts over the ocean. They begin as groups of thunderstorms near the equator during early summer to early fall. The water vapor is the fuel for the hurricanes; the eye wall is the strongest winds occur. By the time a hurricane reaches shore, it can be 500 miles wide; its winds can blow at speed over 150 miles per hour. Hurricane winds can blow down office buildings, piers, power lines, homes and trees.

I feel these photos are relevant because all catastrophes can cause massive destructions and losses of property even human lives.

Most of the natural disasters can not be controlled by humans, however, we can learn to predict/forecast/prevent before hand; we can well prepare ourselves and other people when the disaster strikes and try to minimize the losses.

We should increase people’s awareness on the environment; educate people to use renewable resources and encourage people to use natural resources properly.

Tips on saving the environment:

Government should enforce the policies to punish those who spoil the environment.
Control the population growth.
Encourage farmers to grow crops in the vertical farms for proper usage of land; avoid over cultivation and over grazing.
Plan our cities in an environment friendly manner.

We can not stop the natural disasters happening; however, we can make our building stronger and plan the escape route in advance in case of earthquakes. We can build dams and dykes to stop rivers overflowing in the lowlands to avoid flooding. Most of all, we need to love our earth and protect it for ourselves and others.