Disaster means a terrible event that causes a great damage / loss to the human beings. It is a situation arising from natural forces where large scale disruption of infrastructure, services etc. occurs. It causes a serious impact on human life, economy and environment. Natural disasters are always severe and sudden.
${tocify}
Types of Disasters
Some disasters are:
(A) Geological: in nature like the earthquakes;
(B) Landslides (rocks slides down from the side of a hill ); Volcanic eruptions etc..
(C) Climatic disasters / Natural calamities: These are of different types affect nations all over the world. Because of the large geographical size of the country, India often faces natural calamities like floods, cyclones and drought occurring frequently in different parts of the country.
1. Major calamities: eg: earthquakes; droughts; floods, tsunamis; cyclones etc
2. Minor calamities: eg: hailstorms; avalanches; fire accidents
(D) Man induced disasters include wars, battles, riots, rail/road accidents, nuclear explosions.
The disaster Management
The natural disaster management involves the following steps:
Relief measures
It include rescue tools; communication equipments; heavy machines to remove debris; water pumps; technicians; drugs, doctors, ambulances..
Disaster predictions
The predictions of natural hazards may be made on the basis of past history of the area with regular monitoring of the environmental changes caused by human activities to assess the genesis of natural disasters.
Education
Disaster education plays a significant role in disaster education. It create awareness and improve the standards to prevent from the disasters.
Geographic Information Systems (GIS)
GIS is a system that captures, stores, analyzes, manages and presents data with reference to geographic location of the area. In simple terms, GIS is the merging of cartography, statistical analysis and database technology. GIS may be used in Archaeology, Geography, Remote Sensing, Land surveying; Natural Resource Management; Urban Planning etc. GIS programs help by means of maps available data of the problem areas, to predict the severity of the disaster.
Floods
Floods are high stream flow that overflows the natural banks of the rivers and most of the times become calamitous. India is the most flood affected nation after Bangladesh. Out of total deaths by Floods in the world, (1/5) are from India. The main causes of floods are excessive rains in river catchments, poor natural drainage, Change of river course, Landslide restricting river flow, cyclone and very intense rainfall. Over that past few years the rise in population is forcing large settlements along the river banks, making the country highly vulnerable to Floods. The most vulnerable states of India are Uttar Pradesh, Bihar, Assam, West Bengal, Gujarat, Orissa, Andhra Pradesh, Madhya Pradesh, Maharashtra, and PunjabandJammu&Kashmir. In 1994, a major flood killed 147 people in Kerala, 138 in Gujarat and marooned 10000 in Madhya Pradesh. In 1995, the states of Uttar Pradesh, Haryana and Arunachal Pradesh were severely hit by flood causing huge casualties. In the year 1996, a fierce flood literally paralyzed India, Thousands of people died, got homeless, were marooned in the states of Rajasthan, Andhra Pradesh, Jammu & Kashmir also affecting many other parts of the country. In short, nearly every year one or the other part of the country is severely hit by Floods and creating a shameful history for India. It is high time that the policies and measures for various preventions and disaster management activities are properly implemented. Development of flood risk maps, flash flood run off modeling, water logging problems, systems for monitoring and management of flood using remote sensing and GIS.
Earth-quakes
Earthquakes occur due to the sudden movements in the earth crust. The earth’s crust has several tectonic plates of solid rocks which slowly move along their boundaries. When friction prevents these plates from slipping, stress builds up and results in the sudden fractures which occur along their boundaries of the plates or fault lines (planes of weakness) within the plates. This causes earthquakes, the violent, short term vibrations in the earth. The point on a fault at which the first movement occurs during an earth quake is called the epicenter. The severity of an earthquake is generally measured by its magnitude on RichterScale.
Damage to property and life can be prevented by monitoring of buildings and structures under Strong Earth Motion, experimental and analytical investigations on structures to predict their behavior under earthquake conditions, strengthening through retrofits, development of earthquake resistant design methodologies, better materials, risk assessment, preparation of seismic codes, seismic zonation and development of risk specific designs.
Landslides
Landslides are mass movement of rocks and debris that usually follow a cyclone, volcano or earthquake. In the hilly areas of India, the sliding of huge masses of land has been a common natural disaster causing havoc to life and property. One of the worst and most disastrous landslides has been recorded in the year 1998 in the state of Uttarakhand, when nearly 380 people were killed. As a measure of concern many committees and other measures have been taken to protect from this natural havoc in India. In India, the regions of Himalayas and the Western ghats are the most vulnerable to these land-slides. The main causes of landslides are weak, weathered materials, physical property variation, Ground Uplift, erosion, Earthquake, Volcanic eruptions etc. The general and simple mitigation that are adopted or should be adopted are drainage correction, proper land-utilization, reforestation and spreading of awareness.
Cyclones
Cyclone refers to a whirl in the atmosphere with very strong winds circulating around it in anticlockwise direction in the Northern Hemisphere and clockwise in the Southern Hemisphere. Cyclones are intense low pressure areas with pressure increasing outwards. Cyclones can be hazardous as Cyclones are normally associated with strong winds. A storm surge is an abnormal rise of sea level near the coast caused by a severe tropical cyclone; as a result, sea water inundates low lying areas of coastal regions drowning human beings and lives- stock, eroding beaches and embankments, destroying vegetation and reducing soil fertility. Apart from strong winds, cyclones can result in heavy rains causing floods. However, the most destructive factor associated with the cyclones is the storm surge. The worst and the oldest cyclone in India were in 1737, in Calcutta that took 300000 lives respectively. For cyclone forecast and advance warning, the Government has strengthened the Meteorological Department, by providing Cyclone Surveillance Radars at Calcutta, Paradeep, Visakhapatnam, Machilipatnam, Madras and Karaikal in the east coast and at Cochin, Goa, Bombay and Bhuj in the west coast. As India has a vast coastline it is extremely vulnerable to cyclone.
ratulk12@gmail.com
ReplyDelete