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What are Natural Disasters?

By definition, a natural disaster is an event that is caused by the natural forces of the

earth and results in great damage and possibly loss of life. Each year, the earth

experiences natural disasters. When natural disasters occur in heavily populated areas, a

lot of people may lose their lives. A recent example is the Italian earthquake of 2016,

where over 200 people died. The deadliest of all earthquakes happened in 1556 in China,

where approximately 830,000 people lost their lives.

Let's now take a look at the different types of natural disasters that can happen.

Earthquakes

We'll begin with earthquakes. An earthquake occurs when the earth releases pent-up

energy and causes the ground to shake. Earth's ground is made up of several very large

pieces of land called tectonic plates. Most earthquakes occur when these plates rub

against each other in some way. These same plates also create mountains when they push

against each other. As the mountains are formed, earthquakes may be felt. Sometimes,

people cause earthquakes when they do mine blasts or nuclear tests.

Hurricanes, Typhoons, and Cyclones

Hurricanes, typhoons, and cyclones refer to the same weather phenomenon, where a

really large storm swirls in circles. You'll see the cloud of the storm turning in a spiral,

touch down on the ground, and then reach toward the sky. When a storm reaches a wind

speed of over 74 miles per hour, it gets classified as a hurricane, typhoon, or cyclone

depending on where the storm is located. The storm is called a hurricane if it happens in

the Atlantic and northern Pacific. If the storm occurs in the north western part of the

Pacific, then it is called a typhoon. In the southwestern Pacific and the Indian Ocean, the

same type of storm is called a cyclone.

Tsunamis

A tsunami consists of huge waves caused by either an underwater earthquake or volcanic

eruption. In Japanese, the word means 'harbour wave.' These waves can get as high as

100 feet and aren't the gentle waves that you surf on. No, these are destructive waves

that can knock down buildings, trees, and anything else in their path.

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Floods

A flood is an overflow of water that covers the earth. This overflow can damage

buildings and cars in its path. In a severe flood, the water can seep into houses and

completely cover them, ruining everything. And, if people get caught up in the flood,

they can be washed away with the flood and drown.

Mudslides

Mudslide occur when the ground gets so wet that whatever dirt is on the ground

turns into a liquid mass and flows, like flood, rapidly down a slope. When people or

animals get caught in a mudslide, it is very difficult to get out s the mud drags them

down. If not rescued they will die.

Avalanche

An avalanche is an event that occurs when a cohesive slab of snow lying upon a weaker

layer of snow fractures and slides down a steep slope or mountain.

Wildfires

A wildfire or wildland fire is an uncontrolled fire in an area of combustible

vegetation occurring in rural areas. Depending on the type of vegetation present, a

wildfire can also be classified more specifically as a brush fire, bushfire, desert

fire, forest fire, grass fire, hill fire, peat fire or vegetation fire.

Drought

A drought is a natural disaster of below-average precipitation in a given region,

resulting in prolonged shortages in the water supply, whether atmospheric, surface

water or ground water.

Let us take a detailed look at each Natural disaster.

EARTHQUAKES. (These will be seen, in detail in another topic)

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HURRICANES,TYPHOONES AND CYCLONES are also know as TROPICAL STORMS

What is a hurricane? A hurricane is a large rotating storm with high speed winds that forms over warm waters in tropical areas. Hurricanes have sustained winds of at least 74 miles per hour and an area of low air pressure in the centre called the eye.

Different Names for Hurricanes

The scientific name for a hurricane is a tropical cyclone. Tropical cyclones go by

different names in different places. In North America and the Caribbean they are

called "hurricanes", in the Indian Ocean they are called "cyclones", and in Southeast

Asia they are called "typhoons

How do hurricanes form?

Hurricanes form over the warm ocean water of the tropics. When warm moist air over

the water rises, it is replaced by cooler air. The cooler air will then warm and start to

rise. This cycle causes huge storm clouds to form. These storm clouds will begin to

rotate with the spin of the Earth forming an organized system. If there is enough

warm water, the cycle will continue and the storm clouds and wind speeds will grow

causing a hurricane to form.

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Parts of a Hurricane

•Eye - At the center of the hurricane is the eye. The eye is an area of very low air

pressure. There are generally no clouds in the eye and the wind is calm. Don't let this

fool you, however, the most dangerous part of the storm is at the edge of the eye

called the eye wall.

•Eye wall - Around the outside of the eye is a wall made up of very heavy clouds. This

is the most dangerous part of the hurricane and where the highest speed winds are.

The winds at the eye wall can reach speeds of 155 miles per hour.

•Rain bands - Hurricanes have large spirally bands of rain called rain bands. These

bands can drop huge amounts of rainfall causing flooding when the hurricane hits land.

•Diameter - Hurricanes can become huge storms. The diameter of the hurricane is

measured from one side to the other. Hurricanes can span a diameter of over 600

miles.

•Height - The storm clouds that power hurricanes can become very tall. A powerful

hurricane can reach nine miles into the atmosphere.

Where do tropical cyclones occur?

Tropical cyclones occur over the ocean in areas near the equator. This is because

there is plenty of warm water in these areas to allow the storms to form. There are

seven major areas in the world that tend to produce tropical cyclones. See the map

below.

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When do hurricanes occur?

Hurricanes that form in the Caribbean and the Atlantic Ocean occur between June 1st

and November 30th each year. This is called hurricane season.

Why are hurricanes dangerous?

When hurricanes strike land they can cause huge amounts of damage. Most of the

damage is caused by flooding and storm surge. Storm surge is when the ocean level

rises at the coastline due to the power of the storm. Hurricanes also cause damage

with high speed winds that can blow down trees and damage homes. Many hurricanes

can develop several small tornados as well.

How are they named?

Hurricanes in the Atlantic are named based on a list of names maintained by the World

Meteorological Organization. The names go in alphabetical order and the storms are

named as they appear. So the first storm of the year will always have a name that

starts with the letter "A." There are six lists of names and each year a new list is

used.

Categories

Tropical cyclones are categorized according to the speed of sustained winds.

•Tropical Depression - 38 mph or less

•Tropical Storm - 39 to 73 mph

•Hurricane Category 1 - 74 to 95 mph

•Category 2 - 96 to 110 mph

•Category 3 - 111 to 129 mph

•Category 4 - 130 to 156 mph

•Category 5 - 157 or higher mph

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Interesting Facts about Hurricanes

•Hurricanes rotate counter clockwise in the northern hemisphere and clockwise in the

southern hemisphere. This is due to the rotation of the Earth called the Coriolis ef-

fect.

•The letters Q, U, X, Y, and Z are not used for the first letter when naming hurri-

canes.

•The names are alternated between boy and girl names.

•Weather forecasters draw a cone showing where they think the hurricane is most

likely to travel.

Preparation and prediction

Preparation and prediction techniques can be very different in MEDCs and LEDCs.

MEDCs have the resources and technology to predict and monitor the occurrence of

storms, eg using satellites and specially equipped aircraft. They are also equipped to

train the emergency services appropriately and to educate people about necessary

precautions.

Storm warnings can be issued to enable the population to evacuate or prepare

themselves for the storm. People can prepare by storing food and water or boarding up

their windows.

LEDCs are often less prepared. They may rely on aid (sometimes reluctantly) from

MEDCs for the rescue and recovery process, as was the case with Cyclone Sidr in

Bangladesh, November 2007.

Effects of tropical storms.

The intense winds of tropical storms can destroy whole communities, buildings and

communication networks. As well as their own destructive energy, the winds generate

abnormally high waves and tidal surges. Sometimes the most destructive elements of a

storm are the subsequent high seas and flooding.

MEDCs are better placed to reduce the effects of tropical storms because they have

more financial, educational and technological resources to help deal with them. They

better able to observe and predict storm behaviour and can invest in infrastructure to

withstand storms - as well as spending more money on repairing the damage caused.

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Case study: Hurricane Katrina,2005

Path of hurricane

Katrina

Impacts

•Katrina was a category 4 storm.

•Storm surges reached over 6 metres

in height.

•New Orleans was one of the worst affected areas because it lies below sea level

and is protected by levees. These protect it from the Mississippi River and Lake

Ponchartrain. The levee defences were unable to cope with the strength of Katrina,

and water flooded into the city.

•Despite an evacuation order, many of the poorest people remained in the city.

•People sought refuge in the Superdome stadium. Conditions were unhygienic, and

there was a shortage of food and water. Looting was commonplace throughout the

city. Tension was high and many felt vulnerable and unsafe.

•1 million people were made homeless and about 1,200 people drowned in the floods.

Oil facilities were damaged and as a result petrol prices rose in the UK and USA.

Responses

There was much criticism of the authorities for their handling of the

disaster. Although many people were evacuated, It was a slow process and

the poorest and most vulnerable were left behind.

$50 billion in aid was given by the government.

The UK government sent food aid during the early stages of the recovery

process.

The National Guard was mobilised to restore and maintain law and order in

what became a hostile and unsafe living environment.

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FLOODS

The definition of a flood is land covered by water that is not usually covered by water.

This means that any time a river, lake, or other body of water overflows its banks, it’s

technically flooding. However, most people think of the more catastrophic types of

floods, as those are the type that cause widespread damage and loss of life. Unless a

flood causes some kind of financial damage or loss of life to humans or livestock, it’s

not considered a significant flood.

There are a number of causes for floods, and the most common warning is that floods

can happen anywhere it rains. Just because an area has no history of flooding doesn’t

mean it can’t be flooded at some point. Some floods have happened in areas where

there has been no flooding for hundreds of years, while some flooding happens on a

yearly basis in some areas and countries. In general, flooding is hard to prepare for,

though flood maps are drawn up and in some cases, measures are taken to prevent

heavy flooding in the future.

Flooding causes

Floods cause so much damage because they’re unpredictable and many things can cause

floods. There are flash floods, which happen quickly and rush through. Then there are

slow floods which build up over a period of time. Either way, it’s very hard to predict

exactly how much damage will be done, how to best stop the flow, and most of all, how

to prevent it from happening again.

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There is often loss of life as a result of heavy flooding, causing emotional trauma for

those who have gone through it. Even if people have not been directly affected by the

loss of life, losing property, houses, or land can cause physiological damage. Especially

if the people affected are unable to rebuild due to the houses being too badly damage,

farm land being inundated with salt water, or lack of resources to rebuild, many find

the recovery to be more than just physical.

Damage to property during flooding is often extensive. Vehicles should not be driven

through flooded areas, but often they are caught unaware, creating the need for

replacement or extensive repairs. Houses that have been flooded mildly might survive

with just a good cleaning, but big floods often render homes unlivable without massive

repairs or restructuring. Many personal items are lost forever, such as paper

documents, photographs, clothing, and household items. Furniture and woodwork are

often damaged beyond repair and must be replaced entirely.

In severe floods, communication systems can fail due to lines being broken. Power is

often hindered if power generators and transmission is in some way destroyed or

damaged. Getting power restored after a flood is challenging as water transmits

electricity and can hurt anyone standing in water. If sewage or water systems are

compromised during flooding, water supplies can be contaminated. This can result in

waterborne diseases such as typhoid or cholera among others.

Land that has be saturated often cannot grow new crops for some time. If the water

was saline, such as in flooding near the sea, land will not be able to be cultivated for

some years. Loss of livestock can also result in farmers losing their livelihood and

needing to start over with young animals means losing the profit that would have come

during that time. Any livelihood that depends on farming or ranching can be seriously

affected by floods as farms and ranches often need to be near a body of water in

order to live.

Preparation

Some precautions can be taken, such as creating flood maps and working with nature

to prevent excessive flooding. In some areas levees have been built, but these are not

entirely flood proof. Modern advancements in flood prediction enables people to be

more prepared. These predictions won’t be able to prevent the floods, but enable

people and livestock to get to safety in time. Flood warnings are taken very seriously

as lives depend on it.

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Though there are more causes for floods, these are the most common…

Heavy rainfall: Flooding from rainfall generally happens when more rain falls than

the soil, rivers, and streams can absorb. Tilled fields become swamps, creating a

muddy flood which moves large amounts of sediment. When rivers and streams can no

longer hold water, they start to flood their banks as the water is carried further

down to the next body of water. Soil that is soaked can no longer absorb water and if

the rivers are already full, the water continues to build up. Often, flooding happens

on frozen or concrete ground and the rain cannot be absorbed. Often, the build up of

water and debris can fill up gutters and drainage pipes making it hard for the flood

waters to flow freely into the body of water

Melting snow and ice: Because snow and ice covers large patches of ground, as it

melts, it saturates the ground as it flows into rivers and streams. The rivers are

often thawing as well, making for a higher level of water as it is. Combine the melting

with the rains that usually come in spring, and flooding is likely. Especially during long,

harsh winters, snow and ice can build up, making for a large amount of water needing to

drain out in a relatively short amount of time

Destruction: There are several catastrophic causes for flash floods. These are

often caused by a dam or levee breaking and causing huge amounts of water to come

rushing down onto the plains. The destruction of a dam or levee is often brought on by

another natural disaster, such as a hurricane, cyclone, or earthquake. When a dam or

levee can’t hold the water back anymore, water that is meant to be stored or held back

suddenly crashes down on whatever is in its way, often causing incredible damage in

its wake. Other natural disasters that can cause floods are earthquakes or volcanic

eruptions which bring tsunamis. Hurricanes and cyclones often cause flooding as the

large amounts of water can’t be absorbed or the fast winds cause waves to crash and

flood coastal areas.

River obstructions: There are times when development means changing the natural

course of rivers. In order to clear land for crops or housing, rivers are “guided”

through a different course, often creating conditions for flooding. In many areas

where this happens regularly, the rivers are given back the land, so that extra water

can flow easily. However, there are other times when a river gets blocked by large

sections of ice, debris, or landslides. The build up of water around these areas can

cause serious damage and even loss of lives as it tumbles downstream.

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Case study: Bangladesh

Bangladesh, to the east of India on the Bay of Bengal, is a South Asian country

marked by lush greenery and many waterways. Its Padma (Ganges), Meghna and

Jamuna rivers create fertile plains, and travel by boat is common. On the southern

coast, the Sundarbans, an enormous mangrove forest shared with Eastern India, is

home to the royal Bengal tiger.

CAPITAL DHAKA

POPULATION: 164.7 million (2017)

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Case study: Bangladesh

Bangladesh is a developing country in Asia and it is frequently affected by flooding.

For example, in 2007 flooding made 9 million people homeless and approximately

1,000 people died from drowning and from waterborne diseases.

Causes of flooding in Bangladesh

• Cyclones cause coastal flooding.

• Lots of low-lying land.

• Melt water from the Himalayas.

• Heavy deforestation.

• Heavy monsoon rains. • Increasing urban areas.

What has Bangladesh done to cope with flooding? Bangladesh is a very poor country and so has less money to spend on flood defences

than richer countries. Most people in Bangladesh do not earn enough to pay

for insurance against flooding, so when there are floods they risk losing everything.

Short-term responses to flooding

• Food aid from the Government and other countries.

• Water purification tablets.

• People repaired embankments and helped to rescue people. • Free seed given to farmers. Long-term responses

1. Building embankments.

2. Building raised flood shelters.

3. Introducing flood warning systems.

4. Emergency planning.

5. Dams planned.

6. Reducing deforestation.

Unfortunately, many of these long-term responses are difficult to pay for and

maintain. They are not always successful and don't always help enough people.

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MUDSLIDES

Mudflows can be caused by unusually heavy rains or a sudden thaw. They consist

mainly of mud and water plus fragments of rock and other debris, so they often

behave like floods. They can move houses off their foundations or bury a place

within minutes because of incredibly strong currents.

Heavy rainfall, snowmelt, or high levels of ground water flowing through cracked

bedrock may trigger a movement of soil or sediments. Floods and debris flows may

also occur when strong rains on hill or mountain slopes cause exten-

sive erosion and/or what is known as "channel scour". The 2006 Sidoarjo mud

flow may have been caused by rogue drilling.

Some broad mudflows are rather viscous and therefore slow; others begin very

quickly and continue like an avalanche. If large enough, they can devastate villages

and country sides. They are composed of at least 50% silt and clay-sized materials

and up to 30% water. Mudflows are common even in the hills around Los Angeles,

California, where they have destroyed many homes built on hillsides without

sufficient support after fires destroy vegetation holding the land.

AREAS AT RISK

The area most generally recognized as being at risk of a dangerous mudflow are:

•Areas where wildfires or human modification of the land have destroyed vegetation

•Areas where landslides have occurred before.

•Steep slopes and areas at the bottom of slopes or canyons

•Slopes that have been altered for construction of buildings and roads

•Channels along streams and rivers

•Areas where surface runoff is directed

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CASE STUDY: Vargas tragedy

Vargas tragedy is one of the worst disaster that struck

the Venezuelan country's Vargas state on 15 December 1999. It was a result of

heavy downpour of rain, flash floods and mudslides that followed on 14-16 December

1999 which killed 10,000*30,000 people. This disaster led to an complete collapse of

the infrastructure of the state of Vargas.

Many towns were swept away to the ocean due to the floods. Whole towns like Cerro

Grande and Carmen de Uria completely disappeared. As much as 10% of the popula-

tion of Vargas perished during this event. The coastal area of Vargas has long been

subject to mudslides and flooding: geologically similar catastrophes occurred with

regularity. The most recent major flood was in 1951, however that event did not

cause as much damage.

In a 52-hour span during 14, 15 and 16 December 1999, 91.1 centimetres (35.9 in) of

rain (approximately one year's total rainfall for the region) was measured on the

north-central coast of Venezuela at Simón Bolívar International Airport in Maiquetia,

Venezuela. These heavy rains included 7.2 centimetres (2.8 in) of accumulation in just

one hour, between 6 and 7 AM on the 16th; precipitation on both the 15th and 16th

exceeded the 1,000-year probability rainfall event. Even so, the coast received much

less rain than some regions upstream.

The disaster caused estimated damages of USD $1.79 to $3.5 billion. The death toll

was considered to be between 10,000 and 30,000—the exact number of casualties is

difficult to determine as there

was no reliable census data,

especially about shanty

towns and small communities

that were completely wiped out;

moreover, only some 1,000

bodies were recovered, with the

rest swept to sea by the mud or

buried in the landslides. More

than 8,000 homes and 700

apartment buildings were

destroyed in Vargas displacing

up to 75,000 people.

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AVALANCHE

There is a significant risk of avalanches occurring in glacial areas such as the Alps.

When they happen they can cause widespread disruption, damage and sometimes loss

of life.

Causes and effects of avalanches

An avalanche is a sudden downhill movement of snow. It is a significant hazard to

people living in, or visiting, glacial areas. A slab avalanche is the most dangerous form

of movement. It an be caused by:

• heavy snowfall

• deforestation (for example because of new ski runs) making the slope less stable

• steep slopes, as this helps to increase the speed of movement

vibrations (for example from an earthquake, noise or off-piste skiers)

• Layering of snow - for instance where snow is already on the mountain and has

turned into ice, and then fresh snow falls on top which can easily slide down

• the wind direction piling snow which can overhang a mountain

Effects of avalanches

An avalanche is able to obstruct anything in its path. Roads and railways can be

blocked. Power supplies can be cut off.

A powerful avalanche can even

destroy buildings and people can also

be killed.

90 percent of people who die in

avalanches trigger them themselves.

People usually die from a lack of

oxygen when buried in snow, rather

than from getting too cold.

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Management of avalanches

There are several ways in which avalanches can be managed.

Predicting an avalanche

People try to predict when avalanches are going to occur. The Alps has an avalanches

are going to occur is hard to predict. Historical data, weather information and

information about the actual snow on the mountainside is collected together to try

and forecast the likelihood of an avalanche.

Deliberately causing an avalanche

Avalanches can be started deliberately in order to prevent the snow building up. This

is one of the most important ways of preventing avalanches.

Communicating the risk of an avalanche

Signs of the risk of avalanches can be displayed in villages and also by the ski lifts. In

the Alps the risk is assessed on a five-point scale. Areas can be sealed off which are

considered too dangerous to ski on. Early warning systems are also used.

Land-use zoning

Land can be grouped into red, yellow and green areas.

The red areas are considered too dangerous to be built

on. The orange areas can be built on with restrictions,

such as reinforcing buildings. Roads and railways can be

protected by tunnels over them in the areas where an

avalanche path is likely to travel.

Snow fences and barriers

These can be used to divert and break up the path of the avalanche.

Reforestation

Trees can be planted, increasing stability of the slope and helping to reduce the

damage further down the valley

The areas in which avalanches occur may also be used for human activities, such as

skiing. Villages and towns are also often located in the valleys. It is important for the

people, economy, and the environment that avalanches are managed.

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Case study: THE GALTUR AVALANCHE 1999

Background

Galtür is a popular ski resort in Austria.. Avalanches happen most years, but don't

usually reach the village of Galtür. On 23 rd February 1999, an avalanche raced

down the mountain.

Aftermath

• It travelled at 200 miles per hour, taking 50 seconds to reach the village. 31

people died, 26 of whom were tourists and 5 were locals. Rescuers saved 26 people

in the following 24 hours.

•People in Galtür were stranded as roads were blocked. 16 buildings were destroyed

or severely damaged.

•Ski resorts were closed in the region, costing the industry £5 million for each day

they were closed.

The Saint Bernard is a very important

member of the rescue team after an

avalanche. It helps locate bodies under

the metres of snow and, thanks to the

small barrel of brandy it carries around

its neck, it helps to warm the freezing

survivors, possibly saving their lives.

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WILDFIRES Uncontrolled blazes fuelled by weather, wind, and dry underbrush, wildfirescan

burn acres of land—and consume everything in their paths—in mere minutes.

Forest fires are large uncontrolled fires that take place in the forest. Some of

the fiercest fires occur in the forest because there is so much fuel (trees) to

burn. Forest fires are a type of wildfire. Other types of wildfires include grass

fires, brush fires, and hill fires.

Major Causes of Forest Fires

The major cause of forest fires is human activities. This can be carelessness such

as not putting out a campfire or dropping a lit cigarette. It may also be arson,

which is setting a fire on purpose and is against the law. Around 80% of forest

fires are caused by humans.

Most fires that are started by natural causes are started by lightning. Other

natural causes include volcanic eruptions and sparks from falling rocks. How do

forest fires spread?

There are many factors that contribute to how a forest fire will spread and how

intense the fire will be. They include:

•Weather - The weather has a large impact on how a fire will spread. Fires are

much more likely to start and spread during droughts when the grass and plants

are dry. A strong wind can help a fire to spread and move quickly. The

temperature (how hot it is) and humidity (how dry the air is) will also impact how

well the fire will spread.

•Fuel - Fires need fuel to burn. The type of fuel will impact how quickly the fire

will spread as well as how intense it will be. In a forest there can be plenty of

fuel including trees, leaves, needles, shrubs, and grasses growing beneath the

trees.

•Topography - The topography is the shape and features of the land where the

fire is burning. Fire tends to move faster uphill. Fires may spread quickly up

steep slopes on the sides of mountains and hills.

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How do firefighters put them out?

Forest fires can be extremely difficult to put out or control. Forest fires can be

enormous in size and may quickly change directions. They can move over 6 miles per

hour and can jump over natural gaps such as rivers and roads. That being said modern

firefighters are well trained and know how to control forest fires.

Two of the main techniques used in controlling forest fires are the firebreak

and the air drop.

•Firebreak - One of the best ways to stop a fire is to get rid of the fuel (trees,

grass, etc.) that is helping it to burn. Firefighters will often remove the fuel in a long

line ahead of the where the fire is advancing. This line is called a firebreak. When

the fire reaches the firebreak it runs out of fuel and stops spreading.

•Air drop - Sometimes firefighters will use airplanes and helicopters to drop water

or special firefighting chemicals on fires from the air. These aircraft can carry

thousands of gallons of liquid or gel to drop on hard to reach areas of the fire.

Are some forest fires good?

Yes, some forest fires are helpful to the forest. They can clean out debris that has

accumulated below the trees. By burning debris, fires help to enrich the soil and

make room for new trees to grow.

Interesting Facts about Forest Fires

• A crown fire is a fire that spreads quickly by burning across the tops of trees. • Wildfires in the United States typically burn between 4 million and 9 million acres each year. • Billions of dollars is spent every year fighting fires in the United States. • Many fires in southern California are spread by dry hot winds called the Santa Ana winds. • Sometimes the winds around a fire can begin to spin causing a fire tornado to form.

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CASE STUDY– WORST WILDFIRES IN EUROPE

THIS CENTURY

Portugal in 2017

Sixty-four people were killed and 250 injured in the deadliest wildfires in Portugal's

history in June 2017.

The fires burned for five days in the central Leiria region, breaking out at the height

of a summer heatwave. Many of the victims died trapped in their cars by the flames

while trying to escape.

Violent winds fanned the fires, ravaging some 460 square kilometres (around 180

square miles) of hillsides covered with pine and eucalyptus.

In 2003 gigantic fires caused by a heatwave left 20 dead between July and

September in central and southern Portugal.

The summer of 2003 remains the most disastrous in terms of surface destroyed,

with nearly 4,250 square kilometres going up in smoke.

Russia in 2015, 2010

In April 2015 huge fires that started in the Khakassia region of south eastern Sibe-

ria killed 34 people as well as hundreds of cattle and thousands of sheep.

The blaze, which spread as far as Mongolia and practically up to the Chinese border,

also destroyed 2,000 homes and 10,000 square kilometres of land.

Five years earlier, vast swathes of western Russia were ravaged by fires for weeks

during an unprecedented heatwave and drought.

The blazes between July and August 2010

tore through 10,000 square kilometres of

forest, bogs and brushwood, burning entire

villages. Some of the fires came dangerously

close to Russia's top nuclear research centre

in Sarov.

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Greece in 2007

Forest fires killed 77 people at the end of August 2007 in Greece, ravaging 2,500

square kilometres in the southern Peloponnese and the island of Evia, northeast of

Athens.

The fires raged for around 12 days, but most of the victims were killed early on in the

disaster when they became trapped in villages cut off by the flames, some ignoring

orders to evacuate.

France, worst ever in 1949

In the heaviest loss of life in wildfires in France, 82 people were killed battling flames

in the southwest Landes region in August 1949.

The victims—firemen, volunteers and soldiers—were caught in a ball of fire after the

winds suddenly changed direction.

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DROUGHT

Drought is a continuous period of dry weather, when an area gets less than its

normal amount of rain, over months or even years. Crops and oth-

er plants need water to grow, and animals need it to live. Droughts can become

dangerous to people and other land animals; causing famine and even

creating deserts.

Characteristics of droughts

Droughts occur when there is abnormally low rainfall for an extended period of

time. This means that a desert would not be considered in drought unless it had

less rainfall than normal, for a long period of time. Droughts can last from weeks

to months and even years.

Why are some areas more vulnerable to droughts?

Droughts can occur all over the world. However, there is a link between drought

and some climate patterns.

•A lack of water vapour in the atmosphere means there is less precipitation and

more chance of drought. High-pressure systems reduce evaporation and moisture

in the atmosphere.

•El Niño – as the surface temperature of the Pacific Ocean around the central

South American coast increases, storm patterns are disrupted. This phenomenon

is thought to create droughts in Indonesia and Australia.

•La Niña - as the surface temperature of the Pacific Ocean around the central

South American coast decreases, storms are again disrupted and North and South

America are prone to droughts.

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There are three main types of drought:

•Meteorological drought

– when the amount of precipitation received in a specific area is less than the

average.

•Hydrological drought

– when reduced precipitation impacts on water supply, eg there is decreased

streamflow, soil moisture, reservoir and lake levels, and groundwater.

•Agricultural drought

-when the above two types of drought impact on agricultural activities, eg re-

duced soil moisture or reservoir levels required for irrigation.

Case study: the impact of drought in the UK (2004)

The years 2004-06 were one of the driest periods on record in the UK.

South-east England is particularly vulnerable to drought because it has a high

population density. There are 13 million people living in the region and the demand

for water resources is high. There are few reservoirs, which means there is a heavy

reliance on groundwater supplies. Two consecutive dry winters meant that these

supplies were not replenished.

•Hose-pipe bans were introduced in an effort to conserve water.

•Groundwater fell to its lowest level on record.

•Some rivers dried up.

•Low flow in rivers meant that pollution had a greater impact on the environment.

•Kew Gardens introduced a range of measures to con-

serve water, eg only watering newly planted trees and

newly turfed areas.

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CASE STUDY:

The impact of drought in a developed country – Australia

Between 2002 and 2009, the south-east of Australia experienced its worst drought

in 125 years. This was credited to El Niño, where moist trade winds are reversed, so

instead of bringing rainfall to Australia they travelled west towards South America,

leaving south-east Australia with a lack of rainfall. Some scientists believe climate

change exacerbated this drought by also reducing rainfall.

The region most affected was the Murray-Darling River Basin in New South Wales.

This area usually provides 75% of Australia's water, 40% of Australia's agricultural

produce and is home to nearly 2 million people.

This drought had severe agricultural impacts:

•Significant loss of livestock and crops. Some farmers had to sell machinery, land or

even move elsewhere and lose their livelihood.

•With fewer crops and livestock, Australia had to import more food. This increased

the price of food for the whole country.

•Droughts degrade the quality of the soil, affecting farming for years to come.

This drought had severe impacts on the natural ecosystem:

•Wildfires caused by drought destroyed vegetation and animals' habitats.

•Creeks and rivers dried up causing the organisms relying on them to die or migrate.

Increased soil erosion destroyed vegetation and the creatures which relied on it to

survive.