A natural
disaster is the effect of earths natural hazards, for example flood, tornado, hurricane, volcanic eruption, earthquake, heatwave, or landslide. They can lead to financial,
environmental or human losses. The resulting loss depends on the vulnerability
of the affected population to resist the hazard, also called their resilience. If these disasters continue it
would be a great danger for the earth.[1] This understanding is concentrated
in the formulation: "disasters occur when hazards meet vulnerability."[2] Thus a natural hazard will not
result in a natural disaster in areas without vulnerability, e.g. strong
earthquakes in uninhabited areas.[3] The term natural has
consequently been disputed because the events simply are not hazards or
disasters without human involvement.[4] A concrete example of the division
between a natural hazard and a natural disaster is that the 1906 San Francisco earthquake was a disaster, whereas earthquakes are a hazard.
This article gives an introduction to notable natural disasters, refer to the list of natural disasters for a comprehensive listing.
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Contents
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During World War I, an estimated 40,000 to 80,000
soldiers died as a result of avalanches during the mountain campaign in the Alps at the Austrian-Italian front, many of which were caused by artillery fire.[5]
An earthquake
is the result of a sudden release of energy in the Earth's crust that creates seismic waves. At the Earth's surface,
earthquakes manifest themselves by vibration, shaking and sometimes
displacement of the ground. The vibrations may vary in magnitude. Earthquakes
are caused mostly by slippage within geological faults, but also by other events such as
volcanic activity, landslides, mine blasts, and nuclear tests. The
underground point of origin of the earthquake is called the focus. The
point directly above the focus on the surface is called the epicenter.
Earthquakes by themselves rarely kill people or wildlife. It is usually the
secondary events that they trigger, such as building collapse, fires, tsunamis (seismic sea waves) and volcanoes, that
are actually the human disaster. Many of these could possibly be avoided by
better construction, safety systems, early warning and evacuation planning.
Some of the
most significant earthquakes in recent times include:
- The 2004 Indian Ocean earthquake, the third largest earthquake
in recorded history, registering a moment magnitude of 9.1-9.3. The huge tsunamis triggered by this earthquake
cost the lives of at least 229,000 people.
- The 2011 Tōhoku earthquake and tsunami registered a moment magnitude of 9.0. The death toll from
the earthquake and tsunami is over 13,000, and over 12,000 people are
still missing.
- The 8.8 magnitude February 27, 2010 Chile earthquake and tsunami cost 525 lives.[6]
- The 7.9 magnitude May 12, 2008 Sichuan earthquake in Sichuan Province, China.
Death toll at over 61,150 as of May 27, 2008.
- The 7.7 magnitude July 2006 Java earthquake, which also triggered tsunamis.
- The 7.6-7.7 magnitude 2005 Kashmir earthquake, which cost 79,000 lives in Pakistan.
Volcanic eruptions
Volcanoes can cause widespread destruction
and consequent disaster several ways. The effects include the volcanic eruption itself that
may cause harm following the explosion of the volcano or the fall of rock.
Second, lava may be produced during the eruption
of a volcano. As it leaves the volcano, the lava destroys many buildings and
plants it encounters. Third, volcanic ash generally meaning the cooled ash -
may form a cloud, and settle thickly in nearby locations. When mixed with water
this forms a concrete-like material. In sufficient quantity ash may cause roofs
to collapse under its weight but even small quantities will harm humans if
inhaled. Since the ash has the consistency of ground glass it causes abrasion
damage to moving parts such as engines. The main killer of humans in the
immediate surroundings of a volcanic eruption is the pyroclastic flows, which consist of a cloud of hot
volcanic ash which builds up in the air above the volcano and rushes down the
slopes when the eruption no longer supports the lifting of the gases. It is
believed that Pompeii was destroyed by a pyroclastic
flow. A lahar is a volcanic mudflow or landslide.
The 1953 Tangiwai
disaster was caused
by a lahar, as was the 1985 Armero tragedy in which the town of Armero was
buried and an estimated 23,000 people were killed.
A specific
type of volcano is the supervolcano. According to the Toba
catastrophe theory 70 to 75
thousand years ago a super volcanic event at Lake Toba reduced the human population to
10,000 or even 1,000 breeding pairs creating a bottleneck in human evolution.[7] It also killed three quarters of
all plant life in the northern hemisphere. The main danger from a supervolcano
is the immense cloud of ash which has a disastrous global effect on climate and
temperature for many years.
A flood
is an overflow of an expanse of water that submerges land.[8] The EU Floods directive defines a flood as a temporary
covering by water of land not normally covered by water.[9] In the sense of "flowing
water", the word may also be applied to the inflow of the tide. Flooding may result from the volume of water within
a body of water, such as a river or lake, which overflows or breaks levees, with the result
that some of the water escapes its usual boundaries.[10] While the size of a lake or other
body of water will vary with seasonal changes in precipitation and snow melt,
it is not a significant flood unless such escapes of water endanger land areas
used by man like a village, city or other inhabited area. let us take an
example the thane storm which attacked Tamil Nadu.
Some of the
most notable floods include:
- The Huang He (Yellow River) in China floods
particularly often. The Great Flood of 1931 caused between 800,000 and
4,000,000 deaths.
- The Great Flood of 1993 was one of the most costly
floods in United States history.
- The 1998 Yangtze River Floods, in China, left 14 million
people homeless.
- The 2000 Mozambique flood covered much of the country
for three weeks, resulting in thousands of deaths, and leaving the country
devastated for years afterward.
- The 2005
Mumbai floods which
destroyed 1094 people.
- The 2010 Pakistan floods, damaged crops and
infrastructure, claiming many lives.
- Bhola Cyclone, which struck East Pakistan (now Bangladesh) in 1970,
- Typhoon Nina, which struck China in 1975,
- Hurricane
Katrina, which
struck New Orleans, Louisiana in 2005, and
- Cyclone Yasi, which struck Australia in
2011
A limnic eruption occurs when a gas, usually CO2, suddenly erupts from deep lake
water, posing the threat of suffocating wildlife, livestock and humans. Such an
eruption may also cause tsunamis in the lake as the rising gas
displaces water. Scientists believe landslides, volcanic activity, or explosions can trigger
such an eruption. To date, only two limnic eruptions have been observed and
recorded:
- In 1984, in Cameroon, a limnic eruption in Lake Monoun caused the deaths of 37 nearby
residents.
- At nearby Lake Nyos in 1986 a much larger eruption
killed between 1,700 and 1,800 people by asphyxiation.
Tsunamis can
be caused by undersea earthquakes as the one caused in Ao Nang, Thailand, by
the 2004 Indian Ocean Earthquake, or by landslides such as the one which
occurred at Lituya Bay, Alaska.
- Ao Nang, Thailand (2004). The
2004 Indian Ocean Earthquake created the [Boxing Day Tsunami] and disaster
at this site.
- On October 26, 2010, a tsunami
occurred at Sumatra, Indonesia
- On March 11, 2011, a tsunami occurred near Fukushima, Japan and spread through the
Pacific.
Blizzards
are severe winter
storms
characterized by low temperature, strong winds, and heavy snow. The difference
between a blizzard and a snow storm is the strength of the wind. To be a
considered a blizzard, the storm must have winds in excess of 35 miles per
hour, it should reduce the visibility to 1/4 miles, and must last for a
prolonged period of 3 hours or more. Ground blizzards require high winds to stir up snow
that has already fallen, rather than fresh snowfall. Blizzards have a negative
impact on local economics and can terminate the visibility in regions where
snowfall is rare.
Significant
blizzards include:
- The Great Blizzard of 1888 in the United States
- The 2008 Afghanistan blizzard
- The North American blizzard of 1947
- The 1972
Iran blizzard
resulted in approximately 4,000 deaths and lasted for 5 to 7 days.
Cyclone, tropical cyclone, hurricane,
and typhoon are different names for the same phenomenon a cyclonic storm
system that forms over the oceans. The deadliest hurricane ever was the 1970
Bhola cyclone; the deadliest Atlantic hurricane was the Great
Hurricane of 1780 which
devastated Martinique, St. Eustatius and Barbados. Another notable hurricane is
Hurricane
Katrina which
devastated the Gulf Coast of the United States in 2005. .....
Droughts
If a particular
area has no rainfall or less rain than normal for a long period of time is
called drought. It is not only lack of rainfall that causes drought. Hot dry
winds,very high temperature and evaporation of moisture from the ground can
result in conditions of drought.
- 1900 India killing between
250,000 and 3.25 million.
- 1921-22 Soviet Union in which
over 5 million perished from starvation due to drought
- 1928-30 northwest China
resulting in over 3 million deaths by famine.
- 1936 and 1941 Sichuan Province
China resulting in 5 million and 2.5 million deaths respectively.
- In 2006, states of Australia
including South Australia, Western Australia, New South Wales, Northern
Territory and Queensland had been under drought conditions for five to ten
years. The drought is beginning to affect urban area populations for the
first time. With the majority of the country under water restrictions.
- In 2006, Sichuan Province China
experienced its worst drought in modern times with nearly 8 million people
and over 7 million cattle facing water shortages.
- 12-year drought that was
devastating southwest Western Australia, southeast South Australia,
Victoria and northern Tasmania was "very severe and without
historical precedent".
Hailstorms
are rain drops that have formed together into ice. A particularly damaging
hailstorm hit Munich, Germany, on July 12, 1984, causing
about 2 billion dollars in insurance claims.
A summer
heat wave in Victoria, Australia, created conditions which fuelled the massive bushfires in 2009. Melbourne experienced three days in a row of
temperatures exceeding 40°C with some regional areas sweltering through much
higher temperatures. The bushfires, collectively known as "Black
Saturday", were partly the act of arsonists.
The 2010 Northern Hemisphere summer resulted in severe heat waves,
which killed over 2,000 people. It resulted in hundreds of wildfires which
causing widespread air pollution, and burned thousands of square miles of
forest.
A tornado
is a violent, dangerous, rotating column of air that is in contact with both
the surface of the earth and a cumulonimbus
cloud or, in rare
cases, the base of a cumulus
cloud. They are
often referred to as a twister or a cyclone,[11] although the word cyclone is used in meteorology in a wider
sense, to name any closed low pressure circulation. Tornadoes come in many
shapes and sizes, but are typically in the form of a visible condensation funnel, whose narrow end touches the earth
and is often encircled by a cloud of debris and dust. Most tornadoes have wind speeds
less than 110 miles per hour (177 km/h), are approximately 250 feet
(80 m) across, and travel a few miles (several kilometers) before
dissipating. The most extreme tornadoes can attain wind speeds of more than
300 mph (480 km/h), stretch more than two miles (3 km) across,
and stay on the ground for dozens of miles (more than 100 km).[12][13][14]
Well-known
historical tornadoes include:
- The Tri-State
Tornado of
1925, which killed over 600 people in the United States;
- The Daulatpur-Saturia Tornado of 1989, which killed roughly
1,300 people in Bangladesh.
Wildfires are an uncontrolled fire burning in
wildland areas. Common causes include lightning and drought but wildfires may also be started
by human negligence or arson. They can be a threat to those in
rural areas and also wildlife.
Notable
cases of wildfires were the 1871 Peshtigo Fire in the United States, which killed
at least 1700 people, and the 2009 Victorian
bushfires in
Australia.
An epidemic is an outbreak of a contractible disease that spreads at a rapid rate
through a human population. A pandemic is an epidemic whose spread is
global. There have been many epidemics throughout history, such as Black Death. In the last hundred years,
significant pandemics include:
- The 1918 Spanish flu pandemic, killing an estimated
50 million people worldwide
- The 1957-58 Asian flu pandemic, which killed an
estimated 1 million people
- The 1968-69 Hong Kong flu pandemic
- The 2002-3 SARS pandemic
- The AIDS pandemic, beginning in 1959
- The H1N1
Influenza (Swine
Flu) Pandemic 2009-2010
Other
diseases that spread more slowly, but are still considered to be global health
emergencies by the WHO include:
- XDR TB, a strain of tuberculosis that is extensively resistant
to drug treatments
- Malaria, which kills an estimated 1.6
million people each year
- Ebola hemorrhagic fever, which has claimed hundreds of
victims in Africa in several outbreaks
A solar flare is a phenomenon where the sun
suddenly releases a great amount of solar radiation, much more than normal. Some known
solar flares include:
- An X20 event on August 16, 1989[15]
- A similar flare on April 2,
2001[15]
- The most powerful flare ever
recorded, on November 4, 2003, estimated at between X40 and X45[16]
- The most powerful flare in the past 500 years is believed to have occurred
in September 1859[17]
Gamma ray
bursts are the most powerful explosions that occur in the universe. They
release an enormous amount of energy in milliseconds or as long as ten seconds.
They release as much or even more energy than the Sun will in its whole life.
Gamma ray bursts are not rare events because they occur about once every day
and are detected by telescopes both on Earth and in space. Mostly
large masses of stars, bigger than the Sun, can produce a GRB. A GRB of
distances nearer than 8000 light years may cause a concern to life on
Earth. Mainly Wolf-Rayet
stars WR 104 can produce GRB. Astronomers do
believe that the Ordovician–Silurian extinction, the second most destructive
extinction on Earth, might have been due to a GRB
Protection by international law
International law, for example Geneva Conventions defines International Red Cross and Red Crescent Movement the Convention on the Rights of Persons with Disabilities, requires that "States shall take, in accordance with their obligations under international law, including international humanitarian law and international human rights law, all necessary measures to ensure the protection and safety of persons with disabilities in situations of risk, including the occurrence of natural disaster."[18] And further United Nations Office for the Coordination of Humanitarian Affairs is formed by General Assembly Resolution 44/182.|
Contents
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During World War I, an estimated 40,000 to 80,000
soldiers died as a result of avalanches during the mountain campaign in the Alps at the Austrian-Italian front, many of which were caused by artillery fire.[5]
An earthquake
is the result of a sudden release of energy in the Earth's crust that creates seismic waves. At the Earth's surface,
earthquakes manifest themselves by vibration, shaking and sometimes
displacement of the ground. The vibrations may vary in magnitude. Earthquakes
are caused mostly by slippage within geological faults, but also by other events such as
volcanic activity, landslides, mine blasts, and nuclear tests. The
underground point of origin of the earthquake is called the focus. The
point directly above the focus on the surface is called the epicenter.
Earthquakes by themselves rarely kill people or wildlife. It is usually the
secondary events that they trigger, such as building collapse, fires, tsunamis (seismic sea waves) and volcanoes, that
are actually the human disaster. Many of these could possibly be avoided by
better construction, safety systems, early warning and evacuation planning.
Some of the
most significant earthquakes in recent times include:
- The 2004 Indian Ocean earthquake, the third largest earthquake
in recorded history, registering a moment magnitude of 9.1-9.3. The huge tsunamis triggered by this earthquake
cost the lives of at least 229,000 people.
- The 2011 Tōhoku earthquake and tsunami registered a moment magnitude of 9.0. The death toll from
the earthquake and tsunami is over 13,000, and over 12,000 people are
still missing.
- The 8.8 magnitude February 27, 2010 Chile earthquake and tsunami cost 525 lives.[6]
- The 7.9 magnitude May 12, 2008 Sichuan earthquake in Sichuan Province, China.
Death toll at over 61,150 as of May 27, 2008.
- The 7.7 magnitude July 2006 Java earthquake, which also triggered tsunamis.
- The 7.6-7.7 magnitude 2005 Kashmir earthquake, which cost 79,000 lives in Pakistan.
Volcanic eruptions
Volcanoes can cause widespread destruction
and consequent disaster several ways. The effects include the volcanic eruption itself that
may cause harm following the explosion of the volcano or the fall of rock.
Second, lava may be produced during the eruption
of a volcano. As it leaves the volcano, the lava destroys many buildings and
plants it encounters. Third, volcanic ash generally meaning the cooled ash -
may form a cloud, and settle thickly in nearby locations. When mixed with water
this forms a concrete-like material. In sufficient quantity ash may cause roofs
to collapse under its weight but even small quantities will harm humans if
inhaled. Since the ash has the consistency of ground glass it causes abrasion
damage to moving parts such as engines. The main killer of humans in the
immediate surroundings of a volcanic eruption is the pyroclastic flows, which consist of a cloud of hot
volcanic ash which builds up in the air above the volcano and rushes down the
slopes when the eruption no longer supports the lifting of the gases. It is
believed that Pompeii was destroyed by a pyroclastic
flow. A lahar is a volcanic mudflow or landslide.
The 1953 Tangiwai
disaster was caused
by a lahar, as was the 1985 Armero tragedy in which the town of Armero was
buried and an estimated 23,000 people were killed.
A specific
type of volcano is the supervolcano. According to the Toba
catastrophe theory 70 to 75
thousand years ago a super volcanic event at Lake Toba reduced the human population to
10,000 or even 1,000 breeding pairs creating a bottleneck in human evolution.[7] It also killed three quarters of
all plant life in the northern hemisphere. The main danger from a supervolcano
is the immense cloud of ash which has a disastrous global effect on climate and
temperature for many years.
A flood
is an overflow of an expanse of water that submerges land.[8] The EU Floods directive defines a flood as a temporary
covering by water of land not normally covered by water.[9] In the sense of "flowing
water", the word may also be applied to the inflow of the tide. Flooding may result from the volume of water within
a body of water, such as a river or lake, which overflows or breaks levees, with the result
that some of the water escapes its usual boundaries.[10] While the size of a lake or other
body of water will vary with seasonal changes in precipitation and snow melt,
it is not a significant flood unless such escapes of water endanger land areas
used by man like a village, city or other inhabited area. let us take an
example the thane storm which attacked Tamil Nadu.
Some of the
most notable floods include:
- The Huang He (Yellow River) in China floods
particularly often. The Great Flood of 1931 caused between 800,000 and
4,000,000 deaths.
- The Great Flood of 1993 was one of the most costly
floods in United States history.
- The 1998 Yangtze River Floods, in China, left 14 million
people homeless.
- The 2000 Mozambique flood covered much of the country
for three weeks, resulting in thousands of deaths, and leaving the country
devastated for years afterward.
- The 2005
Mumbai floods which
destroyed 1094 people.
- The 2010 Pakistan floods, damaged crops and
infrastructure, claiming many lives.
- Bhola Cyclone, which struck East Pakistan (now Bangladesh) in 1970,
- Typhoon Nina, which struck China in 1975,
- Hurricane
Katrina, which
struck New Orleans, Louisiana in 2005, and
- Cyclone Yasi, which struck Australia in
2011
A limnic eruption occurs when a gas, usually CO2, suddenly erupts from deep lake
water, posing the threat of suffocating wildlife, livestock and humans. Such an
eruption may also cause tsunamis in the lake as the rising gas
displaces water. Scientists believe landslides, volcanic activity, or explosions can trigger
such an eruption. To date, only two limnic eruptions have been observed and
recorded:
- In 1984, in Cameroon, a limnic eruption in Lake Monoun caused the deaths of 37 nearby
residents.
- At nearby Lake Nyos in 1986 a much larger eruption
killed between 1,700 and 1,800 people by asphyxiation.
Tsunamis can
be caused by undersea earthquakes as the one caused in Ao Nang, Thailand, by
the 2004 Indian Ocean Earthquake, or by landslides such as the one which
occurred at Lituya Bay, Alaska.
- Ao Nang, Thailand (2004). The
2004 Indian Ocean Earthquake created the [Boxing Day Tsunami] and disaster
at this site.
- On October 26, 2010, a tsunami
occurred at Sumatra, Indonesia
- On March 11, 2011, a tsunami occurred near Fukushima, Japan and spread through the
Pacific.
Blizzards
are severe winter
storms
characterized by low temperature, strong winds, and heavy snow. The difference
between a blizzard and a snow storm is the strength of the wind. To be a
considered a blizzard, the storm must have winds in excess of 35 miles per
hour, it should reduce the visibility to 1/4 miles, and must last for a
prolonged period of 3 hours or more. Ground blizzards require high winds to stir up snow
that has already fallen, rather than fresh snowfall. Blizzards have a negative
impact on local economics and can terminate the visibility in regions where
snowfall is rare.
Significant
blizzards include:
- The Great Blizzard of 1888 in the United States
- The 2008 Afghanistan blizzard
- The North American blizzard of 1947
- The 1972
Iran blizzard
resulted in approximately 4,000 deaths and lasted for 5 to 7 days.
Cyclone, tropical cyclone, hurricane,
and typhoon are different names for the same phenomenon a cyclonic storm
system that forms over the oceans. The deadliest hurricane ever was the 1970
Bhola cyclone; the deadliest Atlantic hurricane was the Great
Hurricane of 1780 which
devastated Martinique, St. Eustatius and Barbados. Another notable hurricane is
Hurricane
Katrina which
devastated the Gulf Coast of the United States in 2005. .....
Droughts
If a particular
area has no rainfall or less rain than normal for a long period of time is
called drought. It is not only lack of rainfall that causes drought. Hot dry
winds,very high temperature and evaporation of moisture from the ground can
result in conditions of drought.
- 1900 India killing between
250,000 and 3.25 million.
- 1921-22 Soviet Union in which
over 5 million perished from starvation due to drought
- 1928-30 northwest China
resulting in over 3 million deaths by famine.
- 1936 and 1941 Sichuan Province
China resulting in 5 million and 2.5 million deaths respectively.
- In 2006, states of Australia
including South Australia, Western Australia, New South Wales, Northern
Territory and Queensland had been under drought conditions for five to ten
years. The drought is beginning to affect urban area populations for the
first time. With the majority of the country under water restrictions.
- In 2006, Sichuan Province China
experienced its worst drought in modern times with nearly 8 million people
and over 7 million cattle facing water shortages.
- 12-year drought that was
devastating southwest Western Australia, southeast South Australia,
Victoria and northern Tasmania was "very severe and without
historical precedent".
Hailstorms
are rain drops that have formed together into ice. A particularly damaging
hailstorm hit Munich, Germany, on July 12, 1984, causing
about 2 billion dollars in insurance claims.
A summer
heat wave in Victoria, Australia, created conditions which fuelled the massive bushfires in 2009. Melbourne experienced three days in a row of
temperatures exceeding 40°C with some regional areas sweltering through much
higher temperatures. The bushfires, collectively known as "Black
Saturday", were partly the act of arsonists.
The 2010 Northern Hemisphere summer resulted in severe heat waves,
which killed over 2,000 people. It resulted in hundreds of wildfires which
causing widespread air pollution, and burned thousands of square miles of
forest.
A tornado
is a violent, dangerous, rotating column of air that is in contact with both
the surface of the earth and a cumulonimbus
cloud or, in rare
cases, the base of a cumulus
cloud. They are
often referred to as a twister or a cyclone,[11] although the word cyclone is used in meteorology in a wider
sense, to name any closed low pressure circulation. Tornadoes come in many
shapes and sizes, but are typically in the form of a visible condensation funnel, whose narrow end touches the earth
and is often encircled by a cloud of debris and dust. Most tornadoes have wind speeds
less than 110 miles per hour (177 km/h), are approximately 250 feet
(80 m) across, and travel a few miles (several kilometers) before
dissipating. The most extreme tornadoes can attain wind speeds of more than
300 mph (480 km/h), stretch more than two miles (3 km) across,
and stay on the ground for dozens of miles (more than 100 km).[12][13][14]
Well-known
historical tornadoes include:
- The Tri-State
Tornado of
1925, which killed over 600 people in the United States;
- The Daulatpur-Saturia Tornado of 1989, which killed roughly
1,300 people in Bangladesh.
Wildfires are an uncontrolled fire burning in
wildland areas. Common causes include lightning and drought but wildfires may also be started
by human negligence or arson. They can be a threat to those in
rural areas and also wildlife.
Notable
cases of wildfires were the 1871 Peshtigo Fire in the United States, which killed
at least 1700 people, and the 2009 Victorian
bushfires in
Australia.
An epidemic is an outbreak of a contractible disease that spreads at a rapid rate
through a human population. A pandemic is an epidemic whose spread is
global. There have been many epidemics throughout history, such as Black Death. In the last hundred years,
significant pandemics include:
- The 1918 Spanish flu pandemic, killing an estimated
50 million people worldwide
- The 1957-58 Asian flu pandemic, which killed an
estimated 1 million people
- The 1968-69 Hong Kong flu pandemic
- The 2002-3 SARS pandemic
- The AIDS pandemic, beginning in 1959
- The H1N1
Influenza (Swine
Flu) Pandemic 2009-2010
Other
diseases that spread more slowly, but are still considered to be global health
emergencies by the WHO include:
- XDR TB, a strain of tuberculosis that is extensively resistant
to drug treatments
- Malaria, which kills an estimated 1.6
million people each year
- Ebola hemorrhagic fever, which has claimed hundreds of
victims in Africa in several outbreaks
A solar flare is a phenomenon where the sun
suddenly releases a great amount of solar radiation, much more than normal. Some known
solar flares include:
- An X20 event on August 16, 1989[15]
- A similar flare on April 2,
2001[15]
- The most powerful flare ever
recorded, on November 4, 2003, estimated at between X40 and X45[16]
- The most powerful flare in the past 500 years is believed to have occurred
in September 1859[17]
Gamma ray
bursts are the most powerful explosions that occur in the universe. They
release an enormous amount of energy in milliseconds or as long as ten seconds.
They release as much or even more energy than the Sun will in its whole life.
Gamma ray bursts are not rare events because they occur about once every day
and are detected by telescopes both on Earth and in space. Mostly
large masses of stars, bigger than the Sun, can produce a GRB. A GRB of
distances nearer than 8000 light years may cause a concern to life on
Earth. Mainly Wolf-Rayet
stars WR 104 can produce GRB. Astronomers do
believe that the Ordovician–Silurian extinction, the second most destructive
extinction on Earth, might have been due to a GRB
Protection by international law
International law, for example Geneva Conventions defines International Red Cross and Red Crescent Movement the Convention on the Rights of Persons with Disabilities, requires that "States shall take, in accordance with their obligations under international law, including international humanitarian law and international human rights law, all necessary measures to ensure the protection and safety of persons with disabilities in situations of risk, including the occurrence of natural disaster."[18] And further United Nations Office for the Coordination of Humanitarian Affairs is formed by General Assembly Resolution 44/182.|
Contents
|
During World War I, an estimated 40,000 to 80,000
soldiers died as a result of avalanches during the mountain campaign in the Alps at the Austrian-Italian front, many of which were caused by artillery fire.[5]
An earthquake
is the result of a sudden release of energy in the Earth's crust that creates seismic waves. At the Earth's surface,
earthquakes manifest themselves by vibration, shaking and sometimes
displacement of the ground. The vibrations may vary in magnitude. Earthquakes
are caused mostly by slippage within geological faults, but also by other events such as
volcanic activity, landslides, mine blasts, and nuclear tests. The
underground point of origin of the earthquake is called the focus. The
point directly above the focus on the surface is called the epicenter.
Earthquakes by themselves rarely kill people or wildlife. It is usually the
secondary events that they trigger, such as building collapse, fires, tsunamis (seismic sea waves) and volcanoes, that
are actually the human disaster. Many of these could possibly be avoided by
better construction, safety systems, early warning and evacuation planning.
Some of the
most significant earthquakes in recent times include:
- The 2004 Indian Ocean earthquake, the third largest earthquake
in recorded history, registering a moment magnitude of 9.1-9.3. The huge tsunamis triggered by this earthquake
cost the lives of at least 229,000 people.
- The 2011 Tōhoku earthquake and tsunami registered a moment magnitude of 9.0. The death toll from
the earthquake and tsunami is over 13,000, and over 12,000 people are
still missing.
- The 8.8 magnitude February 27, 2010 Chile earthquake and tsunami cost 525 lives.[6]
- The 7.9 magnitude May 12, 2008 Sichuan earthquake in Sichuan Province, China.
Death toll at over 61,150 as of May 27, 2008.
- The 7.7 magnitude July 2006 Java earthquake, which also triggered tsunamis.
- The 7.6-7.7 magnitude 2005 Kashmir earthquake, which cost 79,000 lives in Pakistan.
Volcanic eruptions
Volcanoes can cause widespread destruction
and consequent disaster several ways. The effects include the volcanic eruption itself that
may cause harm following the explosion of the volcano or the fall of rock.
Second, lava may be produced during the eruption
of a volcano. As it leaves the volcano, the lava destroys many buildings and
plants it encounters. Third, volcanic ash generally meaning the cooled ash -
may form a cloud, and settle thickly in nearby locations. When mixed with water
this forms a concrete-like material. In sufficient quantity ash may cause roofs
to collapse under its weight but even small quantities will harm humans if
inhaled. Since the ash has the consistency of ground glass it causes abrasion
damage to moving parts such as engines. The main killer of humans in the
immediate surroundings of a volcanic eruption is the pyroclastic flows, which consist of a cloud of hot
volcanic ash which builds up in the air above the volcano and rushes down the
slopes when the eruption no longer supports the lifting of the gases. It is
believed that Pompeii was destroyed by a pyroclastic
flow. A lahar is a volcanic mudflow or landslide.
The 1953 Tangiwai
disaster was caused
by a lahar, as was the 1985 Armero tragedy in which the town of Armero was
buried and an estimated 23,000 people were killed.
A specific
type of volcano is the supervolcano. According to the Toba
catastrophe theory 70 to 75
thousand years ago a super volcanic event at Lake Toba reduced the human population to
10,000 or even 1,000 breeding pairs creating a bottleneck in human evolution.[7] It also killed three quarters of
all plant life in the northern hemisphere. The main danger from a supervolcano
is the immense cloud of ash which has a disastrous global effect on climate and
temperature for many years.
A flood
is an overflow of an expanse of water that submerges land.[8] The EU Floods directive defines a flood as a temporary
covering by water of land not normally covered by water.[9] In the sense of "flowing
water", the word may also be applied to the inflow of the tide. Flooding may result from the volume of water within
a body of water, such as a river or lake, which overflows or breaks levees, with the result
that some of the water escapes its usual boundaries.[10] While the size of a lake or other
body of water will vary with seasonal changes in precipitation and snow melt,
it is not a significant flood unless such escapes of water endanger land areas
used by man like a village, city or other inhabited area. let us take an
example the thane storm which attacked Tamil Nadu.
Some of the
most notable floods include:
- The Huang He (Yellow River) in China floods
particularly often. The Great Flood of 1931 caused between 800,000 and
4,000,000 deaths.
- The Great Flood of 1993 was one of the most costly
floods in United States history.
- The 1998 Yangtze River Floods, in China, left 14 million
people homeless.
- The 2000 Mozambique flood covered much of the country
for three weeks, resulting in thousands of deaths, and leaving the country
devastated for years afterward.
- The 2005
Mumbai floods which
destroyed 1094 people.
- The 2010 Pakistan floods, damaged crops and
infrastructure, claiming many lives.
- Bhola Cyclone, which struck East Pakistan (now Bangladesh) in 1970,
- Typhoon Nina, which struck China in 1975,
- Hurricane
Katrina, which
struck New Orleans, Louisiana in 2005, and
- Cyclone Yasi, which struck Australia in
2011
A limnic eruption occurs when a gas, usually CO2, suddenly erupts from deep lake
water, posing the threat of suffocating wildlife, livestock and humans. Such an
eruption may also cause tsunamis in the lake as the rising gas
displaces water. Scientists believe landslides, volcanic activity, or explosions can trigger
such an eruption. To date, only two limnic eruptions have been observed and
recorded:
- In 1984, in Cameroon, a limnic eruption in Lake Monoun caused the deaths of 37 nearby
residents.
- At nearby Lake Nyos in 1986 a much larger eruption
killed between 1,700 and 1,800 people by asphyxiation.
Tsunamis can
be caused by undersea earthquakes as the one caused in Ao Nang, Thailand, by
the 2004 Indian Ocean Earthquake, or by landslides such as the one which
occurred at Lituya Bay, Alaska.
- Ao Nang, Thailand (2004). The
2004 Indian Ocean Earthquake created the [Boxing Day Tsunami] and disaster
at this site.
- On October 26, 2010, a tsunami
occurred at Sumatra, Indonesia
- On March 11, 2011, a tsunami occurred near Fukushima, Japan and spread through the
Pacific.
Blizzards
are severe winter
storms
characterized by low temperature, strong winds, and heavy snow. The difference
between a blizzard and a snow storm is the strength of the wind. To be a
considered a blizzard, the storm must have winds in excess of 35 miles per
hour, it should reduce the visibility to 1/4 miles, and must last for a
prolonged period of 3 hours or more. Ground blizzards require high winds to stir up snow
that has already fallen, rather than fresh snowfall. Blizzards have a negative
impact on local economics and can terminate the visibility in regions where
snowfall is rare.
Significant
blizzards include:
- The Great Blizzard of 1888 in the United States
- The 2008 Afghanistan blizzard
- The North American blizzard of 1947
- The 1972
Iran blizzard
resulted in approximately 4,000 deaths and lasted for 5 to 7 days.
Cyclone, tropical cyclone, hurricane,
and typhoon are different names for the same phenomenon a cyclonic storm
system that forms over the oceans. The deadliest hurricane ever was the 1970
Bhola cyclone; the deadliest Atlantic hurricane was the Great
Hurricane of 1780 which
devastated Martinique, St. Eustatius and Barbados. Another notable hurricane is
Hurricane
Katrina which
devastated the Gulf Coast of the United States in 2005. .....
Droughts
If a particular
area has no rainfall or less rain than normal for a long period of time is
called drought. It is not only lack of rainfall that causes drought. Hot dry
winds,very high temperature and evaporation of moisture from the ground can
result in conditions of drought.
- 1900 India killing between
250,000 and 3.25 million.
- 1921-22 Soviet Union in which
over 5 million perished from starvation due to drought
- 1928-30 northwest China
resulting in over 3 million deaths by famine.
- 1936 and 1941 Sichuan Province
China resulting in 5 million and 2.5 million deaths respectively.
- In 2006, states of Australia
including South Australia, Western Australia, New South Wales, Northern
Territory and Queensland had been under drought conditions for five to ten
years. The drought is beginning to affect urban area populations for the
first time. With the majority of the country under water restrictions.
- In 2006, Sichuan Province China
experienced its worst drought in modern times with nearly 8 million people
and over 7 million cattle facing water shortages.
- 12-year drought that was
devastating southwest Western Australia, southeast South Australia,
Victoria and northern Tasmania was "very severe and without
historical precedent".
Hailstorms
are rain drops that have formed together into ice. A particularly damaging
hailstorm hit Munich, Germany, on July 12, 1984, causing
about 2 billion dollars in insurance claims.
A summer
heat wave in Victoria, Australia, created conditions which fuelled the massive bushfires in 2009. Melbourne experienced three days in a row of
temperatures exceeding 40°C with some regional areas sweltering through much
higher temperatures. The bushfires, collectively known as "Black
Saturday", were partly the act of arsonists.
The 2010 Northern Hemisphere summer resulted in severe heat waves,
which killed over 2,000 people. It resulted in hundreds of wildfires which
causing widespread air pollution, and burned thousands of square miles of
forest.
A tornado
is a violent, dangerous, rotating column of air that is in contact with both
the surface of the earth and a cumulonimbus
cloud or, in rare
cases, the base of a cumulus
cloud. They are
often referred to as a twister or a cyclone,[11] although the word cyclone is used in meteorology in a wider
sense, to name any closed low pressure circulation. Tornadoes come in many
shapes and sizes, but are typically in the form of a visible condensation funnel, whose narrow end touches the earth
and is often encircled by a cloud of debris and dust. Most tornadoes have wind speeds
less than 110 miles per hour (177 km/h), are approximately 250 feet
(80 m) across, and travel a few miles (several kilometers) before
dissipating. The most extreme tornadoes can attain wind speeds of more than
300 mph (480 km/h), stretch more than two miles (3 km) across,
and stay on the ground for dozens of miles (more than 100 km).[12][13][14]
Well-known
historical tornadoes include:
- The Tri-State
Tornado of
1925, which killed over 600 people in the United States;
- The Daulatpur-Saturia Tornado of 1989, which killed roughly
1,300 people in Bangladesh.
Wildfires are an uncontrolled fire burning in
wildland areas. Common causes include lightning and drought but wildfires may also be started
by human negligence or arson. They can be a threat to those in
rural areas and also wildlife.
Notable
cases of wildfires were the 1871 Peshtigo Fire in the United States, which killed
at least 1700 people, and the 2009 Victorian
bushfires in
Australia.
An epidemic is an outbreak of a contractible disease that spreads at a rapid rate
through a human population. A pandemic is an epidemic whose spread is
global. There have been many epidemics throughout history, such as Black Death. In the last hundred years,
significant pandemics include:
- The 1918 Spanish flu pandemic, killing an estimated
50 million people worldwide
- The 1957-58 Asian flu pandemic, which killed an
estimated 1 million people
- The 1968-69 Hong Kong flu pandemic
- The 2002-3 SARS pandemic
- The AIDS pandemic, beginning in 1959
- The H1N1
Influenza (Swine
Flu) Pandemic 2009-2010
Other
diseases that spread more slowly, but are still considered to be global health
emergencies by the WHO include:
- XDR TB, a strain of tuberculosis that is extensively resistant
to drug treatments
- Malaria, which kills an estimated 1.6
million people each year
- Ebola hemorrhagic fever, which has claimed hundreds of
victims in Africa in several outbreaks
A solar flare is a phenomenon where the sun
suddenly releases a great amount of solar radiation, much more than normal. Some known
solar flares include:
- An X20 event on August 16, 1989[15]
- A similar flare on April 2,
2001[15]
- The most powerful flare ever
recorded, on November 4, 2003, estimated at between X40 and X45[16]
- The most powerful flare in the past 500 years is believed to have occurred
in September 1859[17]
Gamma ray
bursts are the most powerful explosions that occur in the universe. They
release an enormous amount of energy in milliseconds or as long as ten seconds.
They release as much or even more energy than the Sun will in its whole life.
Gamma ray bursts are not rare events because they occur about once every day
and are detected by telescopes both on Earth and in space. Mostly
large masses of stars, bigger than the Sun, can produce a GRB. A GRB of
distances nearer than 8000 light years may cause a concern to life on
Earth. Mainly Wolf-Rayet
stars WR 104 can produce GRB. Astronomers do
believe that the Ordovician–Silurian extinction, the second most destructive
extinction on Earth, might have been due to a GRB
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