A natural disaster can n be defined as a particular natural hazard. It is unforeseen, severe as well as immediate. Pollution, ozone depletion in the stratosphere as well as global warming fall in this particular category. Various natural disasters include earthquakes, cyclones, floods, drought and many more. Among these floods and drought is considered to be manmade disaster instead of natural disaster. Heat, cold waves, avalanches, landslides, severe thunderstorms, flash floods, low level wind shears, hail as well as microburst are also various natural disasters.
The destructive potential of a particular natural disaster had been estimated by the spatial extent as well as severity. Spatial extent up to where the effect of a certain disastrous event might be classified very easily. The classification could be done into small, medium as well as large scales. The overall phenomenon extending from a few kilometres to some tens of kilometres have been termed as small scale. Growth of industrialization as well as unjustified exploitation of various natural resources have brought our ecosystem to a particular verge of non-reversibility as well as imbalance. This had led to a certain threat from a particular set of natural hazards such as pollution, global warming along with ozone depletion on the large or a global scale.
Management of natural disaster
Management of numerous disasters might be classified as systems for early warning, rescue operations, operations for relief, and rehabilitation along with long range planning. The most vital is the early warning systems. Unless sufficient advance notice is usually available, the evacuation of the population is usually affected and cannot be undertaken. There are numerous aspects of the early warning system. One includes the effectiveness of technique for forecasting the disaster with the extent and another one is effective communication of the same to the civil authority responsible for the rescue operations. In some sort of phenomena like cyclones, flood and many more. The time that is available for responding to the hazards is of the order of few days. Hence the early warning, rescue operations and communication are held to be possible. In numerous cases such as flash floods, microburst and many more. The overall response time is of the order of few minutes only, these calls for fast early warning as well as efficient system of communication. the human activities tend to induce hazards such as pollution as well as global warming have already started showing precursors and providing enough time for controlling as well as avoiding the hazards by long term planning. Besides this, in case of earthquakes there are no proved methods that had been evolved for giving any sort of prior warning and hence post hazard mitigating is the only one alternative that is used by individuals. The role of communication for the purpose of developing countries, the overall role of communication in the process of disaster mitigation is very critical. Numerous areas of the country does not have telegraph or telephones. These cannot be provided in a very short span of time that is available for mitigating nor there are resources for doing so.
The people usually are dependent on various existing links, many of which completely break at the time of disasters. There are numerous types available for the purpose of dissemination of the disaster warning along with arranging the mitigations, these mitigations include, links for land lines, underground cable links, microwave along with satellite links. The most effective communication that is likely to stay completely or partially unaffected is the satellite link. This had assumed that various earth stations at the two ends are very suitably located for remaining unaffected. Further link between the earth station and the affected area is normally through microwave, land line that has its own limitation because it might tend to break down.
The effective way of dissemination of warning is named as Disaster Warning System that is used by the IMD for issues of cyclone bulletin to numerous coastal areas. This can be extended to the entire earthquake or flood prone areas. The experience showed that it stays completely unaffected under the severest cyclone condition. This system is usually limited to only one way communication. For the purpose of carrying out effective communication that is two way as well VHF/UHF links must be established from every earth station into the affected areas. The usage of existing policy VHF/UHF link could be made. The only addition required includes the missing link between the closest earth station to the police headquarters. The linking of the police VHF and UHF stations would not involve huge investments. This will be a cost effective as well as reliable communication system for disaster warning along with mitigation.
The theory of the plate tectonics offers a complete comprehensive explanation for the several geological phenomena continental drift, mountain building as well as volcanism along with course and earthquake. as per this particular theory, when the molten mass that was the earth billions of years ago cooled down, the crust that was formed was not one homogeneous piece but is broken into numerous dozens large plates and several smaller ones along with the thickness ranging from the 30 km down to lithosphere at the depth of around 100 kilo meter or so. The plates are in the incessant motion along with speeds of around 1 cm to around 5 cm per year. The mobile jigsaw puzzle is what termed as continental drift, this results in the overall formation of mountains, ocean trenches, midocreanic ridges, volcanoes and seismic energy build up. The place where plates tend to converge or collide a deep range of trench forms and one plate is defeated downwards in the asthenosphere which lies below the crust and the lithosphere. When two or more thick continental plates tend to collide, rocks on the land are very relatively light and hence too buoyant for descending into the atmosphere. The result is a huge zone of crushing along with rocks and other materials being folded and this is how the Himalayas had emerged or in fact are continuing to emerge.
As the deformation of the plate’s margins goes on, energy builds up in rocks in the form of elastic strain that continues till it exceeds their elastic limits and the rocks that provide way. The sudden release of stored elastic energy causes earthquakes. Earthquakes are usually caused with the help of the release of elastic strain energy that is created as well as replenished by the stresses from the collision between the plates between two places. The intense earthquakes occur on numerous boundaries of the plates to the east west and north. Numerous faults are created between the plates, this is caused when this tends to rub against the plate of other country. When a certain earthquake takes place along with a fault line within the plate, it has been called an intra-plate earthquakes take place along the boundaries of the plate. Earthquakes are also caused with the help of volcanic activities. Construction of huge water reservoirs might also take place earthquakes. They are called reservoir induced earthquakes.
All the natural disasters cause loss in some or the other way. This depends on the severity. The lives can be lost in any number of disasters. Falling buildings or trees, freezing into death, being washed away or heat stroke are some of the examples of disasters that cause more loss of lives compared to others and population density affects the death count as well. Hence, there is a loss of property that affects lives of people quarters, transportation, livelihood and means of living. Fields saturated in the salt water after tsunamis take years to grow crops again. Homes destroyed by floods, hurricanes, cyclones, landslides and avalanches, a volcanic eruption or an earthquake are some of the ones that go beyond the repair or undertake a huge amount of time for becoming liveable again. Various personal effects, memorabilia, vehicles as well as documents also take a hit after many natural disasters. The natural disasters which actually affect the people worldwide tend to become more intense as the years go on. Frequency of earthquakes, mega storms as well as heat waves has gone up considerably in previous decades. Heavy population in numerous areas that get hit by the floods, cyclones as well as hurricanes has meant that more lives are lost.
From the above discussion, it had been concluded that in numerous areas, the population has gotten somewhat prepared for the eventuality of disasters and shelters are built for hurricanes and tornadoes. However loss of property is still a problem and predicting many natural disasters is not very easy. Disaster recovery plan allows as well as gives the opportunity to a certain business to be able to recoup from any number of disasters, whether it might be a natural disaster or a fault of equipment to include power loss. The plans could be fairly basic along with goal as well as summary of what is going to happen in the event of a disaster.