A natural disaster is the consequence of the combination of a natural hazard and human activities. Human vulnerability caused by the lack of appropriate emergency management, leads to financial, structural, and human losses. A natural hazard will never be a natural disaster in areas without vulnerability, e.g. strong earthquakes in uninhabited areas.

Geological

An avalanche involves a slide of a large snow (or rock) mass down a mountainside. In an avalanche, lots of material or mixtures of different types of material fall or slide rapidly under the force of gravity.

The cause: a buildup of snow is released down a slope.

Landslides are closely related to an avalanche, but instead of occurring with snow, it occurs involving actual elements of the ground, including rocks, trees, parts of houses, and anything else which may happen to be swept up.
The cause: earthquakes, volcanic eruptions, or general instability in the surrounding land.
Mudslides, or mud flows, are a special case of landslides caused by heavy rainfalls.

Earthquakes may manifest themselves by a shaking or displacement of the ground and sometimes tsunamis. 90% of all earthquakes – and 81% of the largest – occur around the 40,000 km long Pacific Ring of Fire. Many earthquakes happen each day, very few of which are large enough to cause significant damage.
The cause: the movement of tectonic plates. The 2004 Indian Ocean earthquake, one of the largest earthquakes in recorded history, registered 9.1–9.3 on the Richter scale. The huge tsunamis triggered by this earthquake cost the lives of at least 229,000 people.

A volcano is a mountain or hill formed by the accumulation of magma or molten rock. Magma is typically produced at depths of 50 to 60 miles below the surface; volcanic eruptions can be deadly, damaging property and infrastructure. The cause: because liquid magma is less dense than solid rock, it is pushed out of cracks in the Earth’s surface.

A supervolcano is an eruption which is thousands of times larger than a normal eruption. The last eruption of this magnitude occurred over 75,000 years ago at Lake Toba. If such an eruption were to occur today, all animals and humans would die out. The climate would change as well.

Water

Floods are dangerous especially on flat terrains. It causes widespread damage to areas downstream, or less frequently the bursting of man-made dams.
The cause: prolonged rainfall from a storm, including thunderstorms, rapid melting of large amounts of snow, or rivers which swell from excess precipitation upstream.

A Tsunami is a giant wave of water which rolls into the shore of an area, with a height of over 15 m. The highest Tsunami ever recorded was estimated to be 85 m high. It appeared on April 24th, 1771, off Ishigaki Island, Japan. The cause: undersea earthquakes or landslides.

Climatic

Droughts are an abnormally dry period when there is not enough water to support agricultural, urban or environmental water needs. Extended droughts can result in deaths by starvation or disease, and can result in wildfires. The cause: scientists warn that global warming may result in more extensive drought in coming years.

Hurricanes, tropical cyclones, and typhoons are different names for the same phenomenon: a cyclonic storm system that forms over the oceans. A hurricane is declared when the spinning mass of storms reach speed greater than 120 km/h. Hurricane is used for these phenomena in the Atlantic Ocean, tropical cyclone in the Indian and typhoon in the eastern Pacific. The cause: evaporated water comes off of the ocean and becomes a storm.

A tornado can occur individually, or can occur in large tornado outbreaks. They are violent, rotating columns of air which can blow at speeds between 80 and 480 km/h, and possibly higher.
The cause: it’s still a mysterious natural disaster resulting from a thunderstorm.

Natural disasters

Wildfire is an uncontrolled fire burning in wildland areas. Common causes include lightning and drought but wildfires may also be started by man.

An ice storm is a particular weather event in which precipitation falls as ice, due to atmosphere conditions.

A hailstorm is a natural disaster where a thunderstorm produces numerous hailstones which damage the location in which they fall.

A heat wave is a disaster characterized by heat which is considered extreme and unusual in the area in which it occurs.

A blizzard is a severe winter storm condition characterized by low temperatures, strong winds, and heavy blowing snow.

Sinkholes are a localized depression in the surface topography, usually caused by the collapse of a subterranean structure, such as a cave. Although rare, large sinkholes that develop suddenly in populated areas can lead to the collapse of buildings and other structures.

An ice age is a geologic period, but could also be viewed in the light of a catastrophic natural disaster, since in an ice age, the climate all over the world would change and places which were once considered habitable would then be too cold to permanently inhabit. A side effect of an ice age could possibly be a famine (głód), caused by a worldwide

Prevention – International campaigns

In 2000, the United Nations launched the International Early Warning Programme to address the underlying causes of vulnerability and to build disaster-resilient communities by promoting increased awareness of the importance of disaster reduction as an integral component of sustainable development, with the goal of reducing human, social, economic and environmental losses due to hazards of all kinds.

How to prevent ‘natural’ disasters

Experts say that a natural hazard becomes a disaster when people do the wrong things, e.g. in Haiti most of the forest were cut down for fuel. It left the hills unprotected against mudslides. There was no surprise when it became to a disaster.
But how to protect inhabitants of the endangered areas? The civil defense forces should warn people early enough of the coming disaster. When people are not informed they don’t know what to do and where to go to be safe. They just don’t know how to react to the disaster.

For example, after two devastating earthquakes in Turkey in 1999, a study by a local university concluded that 25,000 injuries could have been prevented if large pieces of furniture and other tall heavy objects likely to fall over had been secured to a wall.
Local communities can help themselves by organizing early warning networks, and governments’ role is to make sure that land will be used in a sensible way which includes preventing unplanned urban sprawl, smart environmental policies, and rebuilding only in safe places after disasters.

People have to remember that the mother nature will always be stronger than they are.

Improve your vocabulary!

vulnerability – słabość
avalanche – lawina
landslide – osunięcie ziemi
occur – zdarzyć się
earthquake – trzęsienie ziemi
trigger – wywoływać
molten – roztopiony
abnormally – nienormalnie, niespotykanie
dense – stały, zbity
terrain – teren
blizzard – zamieć śnieżna
sinkholes – geol. miejsce wpływu wód pod powierzchnię terenu]
sprawl – rozwalać