Impact of Earthquake, Cyclones, Cyclone Prone Areas of India Part 4

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Impact of Earthquake

Damage of Property: When earthquake occurs, all buildings from cottage to palaces and stronger skyscrapers are greatly damaged or totally destroyed. Underground pipelines and railway lines are damaged or broken. Dams on river collapse, resultant floods cause havoc.

Human Loss: Duration of tremors of earthquake is normally of only few seconds, but thousands of people may die in this short period. Five severely devastating earthquakes have occurred in India between 1988 and January 26, 2001. Nearly 31000 people lost their lives prematurely. In Bihar earthquake of 1934 and Kangra earthquake of 1905, 10,000 and 20,000 people died respectively. The earthquake that occurred in Gujarat on 26 January, 2001 was devastating and disastrous. More than 25,000 people died due to the impact of this earthquake. The destruction of property was tremendous and could not be estimated properly and exactly.

Changes in River Courses: Sometimes river channels are blocked or their courses are changed due to the impact of earthquake.

Tsunamis: They are caused by earthquake. This is a Japanese word, meaning extremely high sea wave. It wreaks havoc on settlement of coastal areas. It sinks large ships. Tsunami that occurred on 26th December 2004 near coast of Sumatra (Indonesia), had destroyed property worth billions of rupees and more than two lakh people lost their lives in Southeast Asia, India and Sri Lanka.

Origin and Propagation of Tsunamis

Image of Origin and Propagation of Tsunamis

Origin and Propagation of Tsunamis

Cracks and Fissures: Sometimes cracks and fissures develop in roads railway tracks, and fields, making them useless. Well known San Andreas fault formed during the earthquake of San Francisco (California). Landslides and avalanches are also triggered.

Some Do’S and Don’Ts During and After the Earthquake:

  • Don’t run outside, set your family into doorways, under table.

  • Keep away from windows and chimneys.

  • Don’t go near the buildings, high walls, or electric wires.

  • If an earthquake occurs stop driving and keep sitting in the vehicle.

  • Put off domestic fire, and all electrical switches.

  • Leave the house if possible and go to open space.

  • Untie and free pets and domestic animals such as dogs, cats, and cattle.

Cyclones

Cyclone is a violent circular stormy, in which high velocity winds blow from outside to the centre and are associated with torrential rain. In cyclones winds blow in an anticlockwise and clockwise direction in the northern and the southern hemisphere respectively. Cyclones play an important role in the general circulation of the atmosphere. A fully developed cyclone can transfer 3.5 billion tons of warm humid air within an hour.

In India, most of the cyclones occur in the post monsoon season, i.e. from October to December, or in pre-monsoon season from April to May. The life span of a cyclone is generally from 7 to 14 days. The cyclone, with its whole system, moves forward from east to west as in Bay of Bengal with a speed of 15 to 30 km per hour. The cyclone that struck Orissa, originated near Andaman and Nicobar Islands and reached Orissa on 29th October 1999 after many days. The movement of cyclone in a direction is like the movement of a spinning top. Cyclones originate over the sea surface and dissipate as they reach land.

Cyclone Prone Areas of India

The eastern coast of India is the most cyclone affected region. The cyclone prone states are West Bengal, Orissa, Andhra Pradesh, and Tamil Nadu. The western coast is affected by the cyclones which originate in the Arabian Sea. Gujarat on the west coast is most affected by cyclones. The coastal areas and interior of Maharashtra are affected by cyclones too. More cyclones originate in the Bay of Bengal and the Arabian Sea than any other seas of the world.

Tropical Cyclone Hazard Mao of India

Image of Tropical Cyclone Hazard Mao of India

Tropical Cyclone Hazard Mao of India

Devastation by Cyclones

The violent winds of a cyclone destroy whatever come in their way, from thatched cottage to the palaces, forts built of concrete, iron and stones. Trees are uprooted, lines of electricity and communication are destroyed. Torrential rains cause floods. Floods wreak havoc all around. High sea waves are generated in the sea by speedy cyclonic winds. They strike the coastal areas like high wall of water and flood the areas up to 10 to 15 km from the coast. In these areas, houses, crops, roads, buildings, villages, and cities one and all are submerged. Landslides triggered by cyclonic rains are more devastating.

Some Do’S and Don’Ts Before, During and After the Cyclone

  • A cyclone may change direction, speed, or intensity within a few hours, so stay tuned to the radio for updated information.

  • Store or secure loose boards, corrugated iron sheets, old tin boxes, anything else that could become dangerous.

  • Close the windows tightly to prevent them from breakage.

  • Move to the safe shelter built for this purpose, or leave the area on the advice of some authoritative government agency.

  • Open windows of the safe portion of the house if the roof begins to lift.

In Brief, It Can Be Said That:

Among the top ten disaster prone countries, India stands second only after China. More than 6% of the total population bear the brunt of natural disasters. Natural hazard, which devastates life and property, are called disasters. More than 20% of the deaths caused by floods in the world occur in India. Floods are caused by heavy rain, deposition of sediment and tsunami. 65% of cultivated area of India is rain fed.

This is the area where droughts are common. Degradation of environment caused by human activities is also responsible for drought. By adopting some measures, the impact of drought could be mitigated. 191 districts, out of the 593 districts of India in 2001 are vulnerable to drought. Landslides cause heavy damage on mountainous slopes in rainy season.

Jammu and Kashmir, Himachal Pradesh, Uttarakhand, Sikkim and all the seven states of North East India are landslide prone. Landslides are caused by deforestation, earthquakes, construction of roads and buildings, and shifting agriculture. Earthquakes not only destroy life and property, but also changes the courses of rivers. The earthquake prone areas are North East India, Gujarat, Uttarakhand, Himachal Pradesh and Jammu and Kashmir.

Cyclones originate in the Bay of Bengal and affects the states of eastern coasts. Cyclones that originate in the Arabian Sea have a devastating impact over Maharashtra and Gujarat coast. If some precise precautions are taken, the impact of cyclones could be minimised.

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