Natural Hazards

A natural disaster is the result of when a natural hazard affects humans. The amount of human vulnerability is the factor that leads to financial, environmental, or human impact. The amount of vulnerability that humans may have to a natural hazard can be subsided by proper emergency management, preparedness, and mitigation. The amount of damage and the death toll from a natural disaster usually depends on the ability of the population to resist, prepare, or lessen the affects of a natural disaster. The general notion is that “natural disasters happen when hazards collide with vulnerability. This means that natural disasters do not occur in an area that is not populated by humans.

There are several types of natural disasters that may occur and the type of disaster usually depends on the geographic location in which a population of humans reside. For instance, an avalanche occurs in areas of mountainous terrain and a cold environment. The following natural disasters are common to happen throughout the world:

Avalanche:
An avalanche is defined as a natural disaster caused by a rapid and immense flow of snow that travels down a slope, usually down a mountainous area. An avalanche can occur naturally in a given geographical region, but it may also be triggered by activities of man. An avalanche can mix air and water with the snow that is flowing through terrain and may become powerful enough to entrain ice, rocks and trees. Avalanches always start with the flow of snow however, which differentiates avalanches from such other natural disasters as mudslides, rock slides, and serac collapses.

Earthquake:
A natural disaster that involves a violent and sudden shaking of the earth’s crust (the outermost layer of the earth’s surface). The point of origin of an earthquake is called the “focus” of the earthquake and the area on the earths surface directly above the focus is called the “epicenter”. Earthquakes are not directly responsible for deaths of humans or wildlife, but rather it is the aftereffects that are triggered by an earthquake that makes them so deadly. Earthquakes can cause buildings to collapse, fires to spread, tsunamis to form at sea, and volcanoes to erupt. While earthquakes are generally difficult to predict ahead of time, safety measures can be put into place that could prevent these secondary events from happening or minimizing the damage.

Earthquakes are caused when the earth’s tectonic plates drift into each other. When enough pressure is built up between the two conflicting plates, they release energy that causes the ground to shake violently.

Flood:
Floods are an overflow of water that submerges land. They usually occur when a nearby body of water, such as a river or lake, overflows and water escapes to areas of dry land. Floods are not considered natural disasters unless the submerged areas reach an inhabited region, such as a village or a town.

Tornadoes:
A natural disaster that involves a violent and dangerous rotating column of air that touches a cloud and the surface of the earth. The winds in a tornado are powerful enough to effortlessly destroy buildings, structures, and anything in its path.