Cyclone

What Is A Cyclone?:-

The word cyclone is derived from the Greek word ‘cyclos’ meaning coils of snake. Cyclones are huge revolving storms caused by wind blowing around the central area of low atmospheric pressure. It is a swirling atmospheric disturbance, accompanied by powerful winds (sometimes exceeding 300 km/hr) blowing in a clockwise direction in northern hemisphere and anticlockwise in southern hemisphere, by pouring rain and generating enormous waves in ocean. They are also called hurricanes and typhoons.



How Do Cyclones Occur?:-


Cyclones develop over warm seas near the equator. Air heated by the sun rises very swiftly which creates areas of very low pressure. As the warm area rises, it becomes loaded with moisture which condenses in to massive thunder clouds. Cool air rushes in to fill the void that is left, but because of the constant turning of the earth on its axis, the air is bent inwards and then spirals upwards with great force. The swirling winds rotate faster and faster forming a huge circle which can be upto 2,000, km across. At the center of storm it is a calm, cloudless area called the eye where there is no rain, and the winds are fairly light. As a cyclone builds, it begins to move. It is sustained by a steady flow of warm moist air.

Impacts Of A Cyclone:-


Cyclones create several changes for people living around tropical areas. The most destructive forces of a cyclone comes from the fierce winds which are strong enough to easily topple fences, sheds, trees, power poles and caravans, which hurling helpless people through air. Many people are killed when the cyclones winds cause buildings to collapse and houses to completely flow away.

Preparing For Cyclones:-


If a cyclone is predicted, the following things should be done:
(i) Clean your residence or work area of unwanted material and rubbish.
(ii)Trim trees of excess height and growth to enable them to withstand higher winds.
(iii)Clean drains of rubbish or obstruction.
(iv) Have available emergency supplies, first aid kits, torch (with batteries), drinking water container, canned food, portable radio (and batteries).
(v)Decides where to shelter pets.
(vi)Organise tie down areas and supplies for caravans, boats, trailers, etc.
(vii)Be ready to evacuate.

Volcano

What Is A Volcano:-

A volcano is a vent or opening in the earth through which hot lava and ash rise to the surface. A cone shaped mountain of erupted material around such a vent is also called a volcano. A volcano consists of a fissure in the earth’s crust, above which a cone of volcanic matter has accumulated. At the top of cone is a bowl shaped vent called a crater. The cone is formed by the deposition of molten matter or solid matter that flows or is ejected through the vent from the interior of the earth.

Recent Volcanic Eruptions:-

Several volcanoes have erupted in the past few months-two in Chile (Chaiten and Llaima) and one in Alaska (Okmok). At any given time, approximately 20-50 volcanoes are active worldwide mostly underwater. The eruption on24 Agust79 AD, destroyed the whole ancient city of Pompeii and then Pompeii remained buried for nearly 1700 years.

During A Volcano:-

Volcanoes can never be predicted or prevented. The only thing is that evacuation can be done if the volcano seems to be starting to erupt. During sudden explosions, nothing can be done.

Tsunami

What Is A Tsunami?:-

A tsunami is a series of waves created when a body of water, such as an ocean, is rapidly displaced. Earthquakes, mass movements above or below water, some volcanic eruptions and other underwater explosions, landslides, underwater earthquakes, large asteroid impacts and testing with nuclear weapons at sea all have the potential to generate a tsunami. The effects of a tsunami can be devastating due to the immense volumes of water and energy involved. Tsunami refers to "Seismic sea waves". The term tsunami comes from the Japanese meaning harbor and wave. Tsunamis are often referred to popularly as tidal waves although they have nothing to do with tides.

Signs Of A Tsunami:-

There is often no advance warning of an approaching tsunami. However, since earthquakes are often a cause of tsunami, any earthquake occurring near a body of water may generate a tsunami. Before a tsunami comes, there is a sudden drawback of water, which is the first sign of an approaching tsunami. If a person is in a coastal area where the sea suddenly draws back, their only real chance of survival is to run for high ground or seek the high floors of high rise buildings.

Destruction Caused By A Tsunami:-

Usually, a tsunami starts suddenly. It will begin as normal waves and change to a very big wave very quickly. The waves travel at a great speed across an ocean with little energy loss. They can remove sand from beaches, destroy trees, damage houses and even devastate whole towns.

Shocking Incident:-

The deadliest tsunami recorded was on December 26, 2004. It was caused by an earthquake. The earthquake was said to had magnitude 9.3 on the Richter scale. It was centered in the ocean near the coast of Sumatra, Indonesia. Over 225,000 people died from this disaster. The giant wave moved very quickly. Hundreds of thousands of people in Indonesia, Sri Lanka, Thailand, India, Somalia, and other nations, were killed or injured by it.

Preventions:-

Tsunamis cannot be prevented, but there are ways to help stop people from dying from a tsunami. Some regions with a high risk of tsunamis may use warning systems to warn the general population before the big waves reach the land. Because an earthquake that caused the tsunami can be felt before the wave gets to the shore, people can be warned to go somewhere safe.

Terrorism

What Is Terrorism:-

Terrorism is the systematic use of terror especially as a means of coercion. There is no internationally agreed definition of terrorism. Most common definitions of terrorism include only those acts which are intended to create fear (terror).Some definitions also include acts of unlawful violence and war. The modern English term "terrorism" dates back to 1795 when it was used to describe the actions of the Jacobin Club in their rule of post-Revolutionary France, the so-called "Reign of Terror". In the present time, terror attacks usually refer to bomb attacks. Terrorists almost invariably pretend to be non-combatants, hide among non-combatants, fight from in the midst of non-combatants, and when they can, strive to mislead and provoke the government soldiers into attacking the wrong people, that the government may be blamed for it. Acts of terrorism can be carried out by individuals, groups, or states. It has been found that a "terrorist" will look, dress, and behave like a normal person, such as a university student, until he or she executes the assigned mission. Terrorist attacks are often targeted to maximize fear and publicity. They usually use explosives or poison, but there is also concern about terrorist attacks using weapons of mass destruction. Terrorist organizations usually methodically plan attacks in advance, and may train participants, plant "undercover" agents, and raise money from supporters or through organized crime. Communication may occur through modern telecommunications, or through old-fashioned methods such as couriers.

Staying Alert:-

Stay alert and cautious if the following happen-
(i)You receive a suspicious letter or package.
(ii)You receive a bomb threat.

If There Is A Terrorist Attack:-

(i)Always stay calm.
(ii)Know the facts. Watch the news to get instructions.
(iii)Be ready to evacuate.
(iv)Check to see if you or anyone around you is injured. Give necessary first aid.
(v)Do not light matches or candles. Do not turn on electrical switches or any appliances.
(vi)Check for gas leaks.
(vii)Assist the elderly

Hi!

So, hello everyone - my first post.I will be shortly posting about disaster management.