Biologia

Disaster
Classifications
Researchers have been studying disasters for more than a century, and for more than forty years research. The studies reflect a common opinion when they argue that all disasters can be seen as being human-made, their reasoning being that human actions before the strike of the hazard can prevent it developing into a disaster. All disasters are hence the result of humanfailure to introduce appropriate disaster management measures. Hazards are routinely divided into natural or human-made, although complex disasters, where there is no single root cause, are more common in developing countries. A specific disaster may spawn a secondary disaster that increases the impact. A classic example is an earthquake that causes a tsunami, resulting in coastal flooding.human-caused disaster. Natural disaster.

Natural disaster
A natural disaster is a consequence when a natural hazard affects humans and/or the built environment. Human vulnerability, and lack of appropriate emergency management, leads to financial, environmental, or human impact. The resulting loss depends on the capacity of the population tosupport or resist the disaster: their resilience. This understanding is concentrated in the formulation: "disasters occur when hazards meet vulnerability". A natural hazard will hence never result in a natural disaster in areas without vulnerability.
Various phenomena like earthquakes, landslides, volcanic eruptions, floods and cyclones are all natural hazards that kill thousands of people and destroybillions of dollars of habitat and property each year. However, natural hazards can strike in unpopulated areas and never develop into disasters. However, the rapid growth of the world's population and its increased concentration often in hazardous environments has escalated both the frequency and severity of natural disasters. With the tropical climate and unstable land forms, coupled withdeforestation, unplanned growth proliferation, non-engineered constructions which make the disaster-prone areas more vulnerable, tardy communication, poor or no budgetary allocation for disaster prevention, developing countries suffer more or less chronically by natural disasters. Asia tops the list of casualties due to natural disasters.

Conclusion
Natural disasters have a different origin fornature and partly because of the pollution caused by people. Some factors can cause uncontrolled land, not only is the pollution and not the internal motion of the earth which causes all natural disasters we witnessed in this era.
Natural disasters occur when individuals or communities become involved in potentially dangerous events such as extreme levels of rainfall, temperature, wind or tectonicmovements, and when people are unable to withstand or recover from the shock of impact.
Natural disasters destroy the progress of the development, but development processes themselves increase the risk of disaster. To reduce material losses in the case of buildings, they need to be sustainable in the long term, it is not enough to make buildings, but they must be resistant to natural threats andthose who used must be prepared to act in disaster.

Introduction

A disaster is an event that causes harm to people, the planet, ecology and especially health.

In a disaster the population or part of it, suffers severe damage and incurs losses for their members, so that the social structure of adjustment and prevents compliance with the essential activities of society affecting the lifefunctioning of the same.

Natural phenomena are presented each year in different ways and although some impact in communities more than others, all affect thousands of people.
Moreover each disaster occurred lasting effects, many lives are lost, damage to property, services and ecology are countless and we all pay the price, but especially those living in high risk areas.

Disasters are...