What is a natural disaster?
A natural disaster maybe defined as a major adverse occurrence resulting from natural processes of the Earth. The severity of the disasters is measured in lives lost, economic loss, loss to the environment, like in the case of forest fires and the ability of the population for rebuilding or reconstruction.
Effects of natural disasters
Sometimes the loss of property affects the living spaces of people, their transportation, livelihood, and means to live, which is agriculture, communication, irrigation, power projects in both rural and urban settlements.
Sometimes the natural disasters are of such huge scales, that the cost and time involved in reconstructing the infrastructure can affect the economy of the geographical region.
Difference between natural and man made disasters
Man-made disasters are caused due to human error or negligence. Some man-made disasters are so severe, they also set off natural disasters, like loss of the marine ecosystem, animal life, affecting or polluting water resources, destruction of natural resources.
Man Made Disasters
Negligence of humans
Types of Disaster
Oil Spilling, Nuclear bombing and testing, Terrorism, Pollution
Tsunami, Floods, Droughts, Wild Fires, Earthquakes, Cyclones etc.
Proper intervention, inspection
education, ensuring safety measures
Regular surveillance, cautionary measures like evacuation, setting up counter-disaster systems, search and rescue, provision of emergency food, shelter, medical assistance etc.
Types of natural disasters
Natural disasters can be classified under the following categories.
Earthquakes are usually brief but maybe repetitive. They are caused by the sudden release of energy in the earth’s crust, creating seismic waves, which can cause a lot of damage both on the surface and under the surface, sometimes causing landslides. When earthquakes occur in the ocean, they cause tsunamis.
2. Avalanches and landslides:
Avalanches and landslides occur in high altitudes, avalanches specifically in snowy areas and landslides on mountain and hillsides.
They can be triggered by overloading of snow or surface weight, the slope angle, melting snow, rains, or water cascades, and vibrations. Sometimes, they are caused by noise as well, like thunder, or explosions, even shouting or screaming.
- Sinkholes are caused by the collapse of large amounts of the earth’s surface into itself, becoming a huge gaping hole in the surface, due to the dissolution of salts, which cause the surface to become weak in places. It is a natural erosion process. It may be caused by torrential rains as well.
- Sinkholes in the sea offer scuba divers exciting places to explore.
- Sinkholes are also used as garbage dumping grounds, causing severe damage to groundwater.
Flooding is the submerging of land not generally submerged, by the overflowing of water. The overflow may occur from a water catchment/reservoir, or from a lake or sea or any other water body.
5. Volcanic eruptions:
Volcanic eruptions occur when a volcano erupts and throws out hot materials like molten rocks(lava), rocks, ash, and dust. Because lava flowing from volcanoes is so hot, it destroys as it flows.
A tsunami or a tidal wave is caused by a large displacement of water, in the ocean. They are seismic waves and do not resemble any other kind of sea wave or currents or tides, which are caused by wind or the lunar cycles. They reach dangerous heights and destroy the coastlines. Japan is prone to tsunamis.
7. Cyclonic storms:
Cyclones are large masses of air, that rotate, spiral around a very strong center with a low atmospheric pressure. It is called a typhoon in Northwest Pacific, a hurricane in Central America. Cyclones can cause severe destruction if they are moving at very high speed, uprooting trees and destroying buildings. They also carry storms and bring in torrential rains, which may cause flooding.
Droughts are caused by lack of rainfalls and can cause severe losses to agricultural industry and communities that are dependent on rain and agriculture. Over centuries, droughts have caused several severe famines, causing thousands to die of starvation and suicides.
A tornado is a rapidly rotating column of air that is in contact with both the Earth’s surface and a cumulonimbus cloud or in some rare cases cumulus cloud. Tornadoes cause severe damage uprooting as they move along at really high speed. They are also known as twisters.
Wildfires or forest fires are uncontrolled fires burning in wildland areas. They can be caused by lightning or volcanic eruptions, or even human carelessness or arson. Wildfires can destroy acres of precious forests which has taken years to grow resulting in loss of both flora and fauna.