# data[].attributes.body
Choose the correct option:
1. When rocks that are carried by the river scrape away the bed and banks it is called:

Hydraulic action

Abrasion

Attrition

2. When soluble particles are dissolved into the river it is called:

Hydraulic action

Abrasion

Solution

3. Which process involves small pebbles and stones being bounced along the river bed?

Traction

Saltation

Solution

4. Which process involves large boulders and rocks being rolled along the river bed?

Traction

Saltation

Solution

5. Which of the following is NOT a type of river erosion?

Abrasion

Percolation

Attrition

6. When rocks and pebbles being carried by the river knock together and are broken down to form smaller particles, this is called:

Corrosion

Abrasion

Attrition

7. When the force of the water being carried by the river wears away the bed and banks, this is called:

Solution or corrosion

Hydraulic action

Percolation

8. Which of the following statements about deposition is NOT correct?

Deposition is more common at the source of the river

Deposition may occur when the river is shallow

Deposition may occur when the volume of water decreases

9. Erosion is vertical or downwards:

At the source of a river

At the mouth of a river

Throughout the entire river profile

10. A wide river channel is formed:

At the source of a river

At the mouth of a river

In the middle section of a river

# data[].attributes.body
Economic Growth in the 1920s
This decade was a period of prosperity: incomes rose and standards of living improved.
The stock market boomed and many people bought shares.
The motor industry boomed as cars became more affordable. Ford and General Motors all became huge companies.
The Model T Ford cost less than $300.
More people could afford to buy items such as fridges, radios, washing machines and vacuum cleaners.

Prohibition
In 1920 it became illegal to manufacture, produce or distribute alcohol. This was called prohibition.
Temperance movements believed that alcohol led to violence, immoral behaviour and the breakdown of family life.
Businessmen blamed alcohol for making workers lazy and unreliable and the middle classes believed alcohol caused social problems among immigrant workers.

Organised Crime
Prohibition saw a huge rise in organised crime as rival gangs fought to control the business and make millions of dollars.
Al Capone made $60 million per year from alcohol. He used a private army to run his business and fight rival gangs, but was eventually arrested for tax evasion in 1931.
The St Valentine's Day Massacre of 1929, organised by Al Capone against a rival gang, is the most famous incidence of gang violence.
Prohibition had proved almost impossible to enforce and there was widespread corruption. It ended in 1933

The Wall Street Crash
On 24 October 1929 approximately 13 million shares were sold, but confidence in the value of these shares plummeted.
Loss of confidence led to falling prices and this meant losses of stock for brokers and private investors. This increased pressure on the banks to help peoplr out.
The US economy suffered a depression and there was terrible poverty in the years that followed. Confidence in the economy had been destroyed.
In 1932, approximately 20000 businesses and 5000 banks were forced to close.

Key point
Prohibition failed because the demand for alcohol continued. Criminals moved in to supply alcohol, made huge profits and developed sophisticated criminal networks.

The Wall Street Crash has devastating effect on the US economy which took yeara to fully recover.

What Is Wall Street?
Wall Street is a street located in the lower Manhattan section of New York City and is the home of the New York Stock Exchange or NYSE. Wall Street has also been the historic headquarters of some of the largest U.S. brokerages and investment banks.

Key events:
1920 Prohibition introduced.
On 24 October 1929 The Wall Street Crash.
1929 St Valentine's Day Massacre.
1931 Al Capone arrested.
1933 Prohibition ended.
1945 End of Second World War.

# data[].attributes.body
3. Deposition

When a river loses energy, it will drop or deposit some of the material it is carrying.

Deposition may take place when a river enters an area of shallow water or when the volume of water decreases - for example, after a flood or during times of drought.

Deposition is common towards the end of a river's journey, at the mouth.

Deposition at the mouth of a river can form deltas - for example, the Mississippi Delta.

The Mississippi Delta

# data[].attributes.body
2. Transport

Rivers pick up and carry material as they flow downstream.

The four different river transport processes

Solution - minerals are dissolved in the water and carried along in solution.

Suspension - fine light material is carried along in the water.

Saltation - small pebbles and stones are bounced along the river bed.

Traction - large boulders and rocks are rolled along the river bed.

Rivers need energy to transport material, and levels of energy change as the river moves from source to mouth.

When energy levels are very high, large rocks and boulders can be transported. Energy levels are usually higher near a river's source, when its course is steep and its valley narrow. Energy levels rise even higher in times of flood.

When energy levels are low, only small particles can be transported (if any). Energy levels are lowest when velocity drops as a river enters a lake or sea (at the mouth).

# data[].attributes.body
River processes shape the land in different ways as the river moves from its source to its mouth. Erosion, deposition and materials rivers carry all contribute to how rivers shape surrounding land.

1. Erosion

Erosion involves the wearing away of rock and soil found along the river bed and banks. Erosion also involves the breaking down of the rock particles being carried downstream by the river.

The four main forms of river erosion

Hydraulic action - the force of the river against the banks can cause air to be trapped in cracks and crevices. The pressure weakens the banks and gradually wears it away.

Abrasion - rocks carried along by the river wear down the river bed and banks.

Attrition - rocks being carried by the river smash together and break into smaller, smoother and rounder particles.

Solution - soluble particles are dissolved into the river.

# data[].attributes.body
On 1 September 1939 Germany invaded Poland.
On 3 September Britain and France declared war on Germany.
By April 1940 Germany had invaded Holland and France. The Speed of the German attacks - known as Blitzkrieg (lightning war) - took the Allies by surprise.

Dunkirk 'Operation Dynamo'
British and France troops had been pushed back to the beaches of Dunkirk. They were now trapped between the German army and the English Channel. The only chance to escape by the sea. In May 1940 the British government put a plan into action known as Operation Dynamo. The aim was to evacuate 300,000 solidiers by ship from the beaches of Dunkirk. The Royal Navy was used to transport men safely from Dunkirk, and many solidiers were rescued using fishing boats and pleasure steamers.
Dunkirk is seen as a great success and a plan of courage and resilience. But it also highlighted the power, force and speed of the German army.

End of the World War II
The Germans were fighting on both the Western and Eastern fronts and were rapidly running out of soldiers and supplies.
On 6 June 1944 the D-Day invasion took place. Nearly 200,000 British and American solidiers landed in Normandy, northern France and began advancing through France towards Germany.
By 1945 it was clear to Hitler and his army that they were going to be defeated.
On 30 April 1945 Hitler committed suicide. The war was over. Germany surrendered.

# data[].attributes.body
▪Adolf Hitler became Chancellor of Germany in 1933. He was later elected as dictator (Fuhrer) of Nazi Germany.
▪Hitler's aims between 1933 and 1939 were:

1. the reunion of Germany and Austria

2. the cancellation of the Treaty of Versailles

3. to destroy communism

4. to gain land in the East, Russia and Eastern Europe for the German people-Lebensraum (living space)

Rearmament

From 1933, Hitlerbegan to secretly build up his army and air force. This had been banned by the Treaty of Vversailles.

Britain and France did nothing to prevent this from happening. They were more worried about the power of the Soviet Union.

The Rhineland and Austria

In 1936, Hitler ordered his troops to march into the Rhineland, which wss forbidden by the Treaty of Versailles.

Many people thought it was reasonable for Germany to have troops protecting its own land.

In 1938 Hitler sent troops into Austria and forced the Austrian leader to hold a vote on unification.

Britain, France and Italy had refused to help Austria because they did not want to risk the possibility of war.

Hitler promised that he wanted peace in Europe.

The Sudetenland and Czechoslovakia

In September 1938 Hitler demanded that the Sudetenland area of Czechoslovakia unite with Germany.

Hitler claimed that people who lived there were German and wanted to unite with Germany.

The British Prime Minister, Neville Chamberlain, visited Hitler three times to attempt to prevent war.

This Policy was known as appeasement. They signed the Munich Pact. Chamberlain declared that this was 'Peace in our time'.

Chamberlain agreed that Hitler could keep the Sudetenland if he promised not to take over the rest of Czechoslovakia.

In March 1939 Hitler broke the Munich Pact and German troops invade the rest of Czechoslovakia.

Poland

In August 1939, Germany and the Soviet Union signed a non-aggression agreement called the Nazi-Soviet Pact.

On 1 September 1939 Hitlet invade Poland.

Britain and France declared war on Germany on 3 September 1939.

Watch this video👀

# data[].attributes.attachment_link.title
'About Us, Without Us': The Day The Munich Agreement Was Signed

# data[].attributes.body
End of the War
The war ended on 11 November 1918 when Germany surrendered. In all, 8 million soldiers and 9 million civilians had died.

Treaty of Versailles
A treaty was made on 28 June 1919 to punish Germany for losing the war. It was signed at the palace of Verdailles, just outside Park, after six months of negotiations.
Germany was banned from the talks. The treaty angered the German people and was later used as propaganda by extremists in Germany.

Key events
War broke out in August 1914.

11 November 1918 the war ended.

28 June 1919 the treaty of Versailles signed.

# data[].attributes.body
Caused by a complex alliance system, the First World War was both brutal and devastating. Fought from trenches, on land and at sea, it ended in countless tragedies and a controversial treaty.

Causes

Historians disagree about what 'caused' the First World War, but most trace it in some degree to the growing power of Germany. The 'balance of power' between the nations of Europe became unstable. This led them to form military alliances:

The Triple Alliance ‒ Germany, Austria and Italy

The Triple Entente ‒ France, Britain and Russia

After the murder of Austrian Archduke Franz Ferdinand in June 1914, Austria-Hungary declared war on Serbia. The countries of Europe found that the alliances they had formed dragged them into war.

Alliances
☆ Russian had an agreement to support Serbia should it go to war.
☆ Germany had an agreement to support Austris-Hungary should it go to war.
☆ Britian and France had an agreement to support Russia.
☆ This meant countries were drawn into the war.

Empires
Britain had a big empire that Germany was jealous of, causing tension.
Many European countries were competing to make their empire bigger.

# data[].attributes.body
Choose the correct option:
1. How much rainfall does the rainforest receive each year?

2,000 mm

1,000 mm

1,500 mm

2. What is the average daily temperature in a tropical rainforest?

20°C

35°C

28°C

3. What colour is the soil in the rainforest?

Red

Orange

Brown

4. How many layers make up a tropical rainforest?

Four

Five

Six

5. Where do epiphytes get their nutrients from?

Soil

Water

The air and water

6. Where do the leaves and flowers of the lianas grow?

In the emergent layer

In the canopy

In the shrub layer

# data[].attributes.headline
Tropical Rainforests - Plant and animal adaptations

# data[].attributes.subject
Tropical Rainforests - Plant and animal adaptations

# data[].attributes.body
Plant adaptations

The following adaptations allow plants to survive in the conditions of the rainforest.

Lianas - these are woody vines that have roots in the ground but climb up the trees to reach the sunlight. Their leaves and flowers grow in the canopy.

Tree trunks - these are tall and thin to allow trees to reach the sunlight. The bark on these trees is smooth to allow water to flow down to the roots easily.

Drip tips - plants have leaves with pointy tips. This allows water to run off the leaves quickly without damaging or breaking them.

Buttress roots - large roots have ridges which create a large surface area that help to support large trees.

Epiphytes - these are plants which live on the branches of trees high up in the canopy. They get their nutrients from the air and water, not from the soil.

Animal adaptations

Many animals have adapted to the unique conditions of the tropical rainforests.

The sloth uses camouflage and moves very slowly to make it difficult for predators to spot.

The spider monkey has long, strong limbs to help it to climb through the rainforest trees.

The flying frog has fully webbed hands and feet, and a flap of loose skin that stretches between its limbs, which allows it to glide from plant to plant.

The toucan has a long, large bill to allow it to reach and cut fruit from branches that are too weak to support its weight.

Glossary
abiotic
Non-living elements of an ecosystem, such as climate, temperature, water, and soil type.

arable farming
When crops are grown.

biodiversity
The range of animals and plants in a given area.

biotic
Living elements of an ecosystem, such as plants and animals.

camouflage

An ability to blend in with a background.

predators
Animals that catch and eat other animals.

species
A type of organism that is the basic unit of classification. Individuals of different species are not able to interbreed successfully.

sustainable
An activity which does not consume or destroy resources or the environment

# data[].attributes.body
Cumulus clouds are the puffy clouds that are usually scattered throughout the sky. In Latin, the word cumulus means pile. Just like when we say “accumulate,” it means things pile up. This type of cloud is formed when warm air rises carrying water vapor with it by evaporation. Cumulus clouds can be white or gray. White fluffy clouds means no rain, but when they form into dark or gray clouds, it is going to rain.

# data[].attributes.body
A big, bright bolt of lightning streaks across the sky. A few seconds later, you hear the rumble and crash of thunder as it shakes the windows in your house. The sky is dark and the rain is pouring down. Those gloomy clouds keeping you from playing outside and having fun are called cumulonimbus clouds.

The word cumulonimbus is formed from two words. Cumulus means 'pile' in Latin, and nimbus means 'rain cloud.' These describe a cumulonimbus cloud perfectly, because it grows up vertically like a billowy pile, and these clouds usually bring rain or other wet weather.

A cumulonimbus cloud can grow more than eleven miles high into the sky. The top of the cloud sometimes gets blown by strong winds and has a flat top, like a table. That flat top is called an anvil, because it looks like the flat metal block called an anvil that's used to hammer metal.

# data[].attributes.body
Tropical rainforests are an imporutant ecosystem with distinct characteristics and adaptations. Tropical rainforests face threats which need to be managed to ensure their survival.

Characteristics of tropical rainforests

Tropical rainforests have distinct characteristics that support a wide variety of different species. This means that they have a high biodiversity. The biotic or living components of the ecosystem and the abiotic or non-living components of the ecosystem depend on one another - a change in one leads to a change in the other.

Climate

Very wet with over 2,000 mm of rainfall per year.

Very warm with an average daily temperature of 28°C. The temperature never drops below 20°C and rarely exceeds 35°C.

The atmosphere is hot and humid.

The climate is consistent all year round. There are no seasons.

Soil

Most of the soil is not very fertile.

A thin layer of fertile soil is found at the surface where the dead leaves decompose.

It is red in colour because it is rich in iron.

Due to heavy rainfall the nutrients are quickly washed out of the soil.

Plants and animals

The warm and very wet climate provides perfect conditions for plant growth.

The wide range of plant species supports many different animals, birds and insects.

Species have adapted to the conditions of the rainforest, eg trees and plants have shallow-reaching roots to absorb nutrients from the thin fertile layer in the soil.

Structure of a tropical rainforest

A tropical rainforest is made up of the following layers:

ground level

shrub layer

under canopy

(main) canopy

emergents

# data[].attributes.body
Choose the correct option:
1.What is weather?

Weather is the day-to-day condition of the atmosphere

Weather is the atmosphere over a 30 year period

Weather is how hot or cold the atmosphere is each day

2.What is precipitation?

The amount of moisture/ rainfall in an area

A measure of temperature in an area

A measure of the amount of pressure in an area

3.What is the instrument used to measure wind speed?

Rain gauge

Anemometer

Barometer

4.What is the instrument used to measure air pressure?

Wind vane

Cloudometer

Barometer

5.The clouds which are found low in the sky and are found grey and shapeless are called...

Cumulonimbus

Cumulus

Stratus

# data[].attributes.body
Clouds come in many different types. Often the type of cloud can help us to understand what type of weather is moving in across an area.

Clouds are categorised according to height and shape. The different categories of clouds are then given names based on Latin words, e.g. nimbus clouds bring rain, stratus clouds appear as layers.

The main clouds that you need to be aware of are:

Stratus: These are layered clouds that are low, grey and shapeless and usually are like a blanket of cloud over an area. They can bring some drizzle and rain.

Cumulus: These are clouds that move quite quickly. They are white and fluffy and look like cotton wool. They can bring rain showers – especially when the base is grey.

Cumulonimbus: These are much deeper clouds that climb high into the atmosphere. They often contain a lot of heavy rain and are associated with thunder and lightning storms.

Cirrus: These are very high clouds that are wispy and made up from ice crystals.

# data[].attributes.body
Weather can affect us in many ways. Meteorologists study weather patterns to predict upcoming changes and hazardous conditions such as storms. Changes in climate occur over a larger span of time.

What is the difference between weather and climate?

Weather describes the day-to-day conditions of the atmosphere. Weather can change quickly - one day it can be dry and sunny and the next day it may rain.

Climate describes average weather conditions over longer periods and over large areas.

The table below shows the world climatic zones.

# data[].attributes.body
Weather affects us in many ways. It affects what we do and what we wear, how we travel and even our moods. Meteorologists measure weather conditions in different places and use this information to report and make forecasts about future weather conditions. This is useful because people can be warned about hazardous weather conditions such as storms and floods.

What do we measure?

Temperature

Precipitation, eg rainfall

Wind speed and direction

Cloud cover and visibility

Air pressure

Humidity (amount of water vapour in the air)

Sunshine

Temperature is measured in Celsius (°C) using a thermometer. The thermometer must be shaded from direct sunlight and should have air circulating around it. The thermometers can be placed in a Stevenson Screen. This is a wooden box with slatted sides, a sloping roof and legs to keep the screen off the ground. It is painted white to reflect the sun.

Precipitation is measured using a rain gauge. This is a funnel inside a graduated container. The depth of the rain in millimetres can be read from the side of the container.

Wind direction is reported by the direction it is blowing from, according to the compass. Wind blowing from the west is travelling eastwards so is called a westerly wind, not an easterly wind.

Wind speed can be measured using an anemometer.

Cloud cover is measured in units called oktas. Each okta represents one eighth of the sky covered by cloud.

Air pressure. Air is light but because there is so much of it above us, it exerts a pressure on us. Air pressure is measured by a barometer. The units used are millibars. The greater the reading, the higher the pressure.

A high-pressure system is called an anticyclone. Air falls in an anticyclone so no clouds are formed. In summer, high pressure usually results in clear skies, gentle breezes and fine weather. In winter high pressure leads to clear skies and colder conditions.

An area of low pressure is called a depression. Air rises in a depression so clouds and rainfall are formed. Depressions therefore bring unsettled weather and rain. Winds are normally stronger. They usually form over the Atlantic Ocean and are carried across Britain by westerly winds.

Key words
anemometer
A device for measuring wind speed.

anticyclone
High-pressure systems, giving clear skies and gentle wind.

atmospheric condition
The state of the air around us, eg temperature, wind speed, cloud cover and humidity levels.

climate
Average weather conditions over longer periods and over large areas.

depression
In meteorological terms, a depression is an area of low air pressure.

graduated container
An object that holds fluids with a measuring scale up the side. These may be used for measuring rainfall amounts.

okta
A unit used to express the extent of cloud cover. It is equal to one-eighth of the area of the sky.

precipitation
Moisture that falls from the air to the ground. Includes rain, snow, hail, sleet, drizzle, fog and mist.

thermometer
An instrument used to measure temperature.

weather
The day-to-day condition of the atmosphere.

# data[].attributes.body
Choose the correct option:
1. Which course of a river is associated with wide flat-bottomed valleys, floodplains and deltas?

Upper

Middle

Lower

2. Which feature is created as a waterfall retreats?

Meander

Gorge

Delta

3. How many courses are rivers usually divided into?

Two

Three

Four

4. V-shaped valleys, interlocking spurs and waterfalls are usually found in which part of a river?

Upper course

Lower-middle course

Lower course

5. Which one of these features do you associate with the lower course of a river?

Meander

Delta

V-shaped valley

6. What is formed where a river in its upper course winds around hard rock forming a series of tapering ridges?

Interlocking spurs

Waterfalls

Floodplain

7. When a river runs over alternating layers of hard and soft rock what is created?

V-shaped valley

Oxbow lake

Waterfall

8. What features are created when a river erodes laterally creating large sweeping bends in the river channel?

Deltas

Floodplains

Meanders

9. When alluvium (silt) builds up on the banks of a river, what are formed?

Deltas

Levees

Gorges

# data[].attributes.body
River drainage basin

A river basin or drainage basin is an area of land drained by a river and its tributaries. The edge of the drainage basin is known as the watershed. This can be compared to a sink or basin, which catches the water falling into it. The water travels towards the centre and leaves the sink through a plug hole. In a similar way, the water flowing through the river will eventually leave the river basin through its mouth and enter the sea or a lake.

Key words:
mouth

The place where a river meets the sea.

river basin

The area drained by a river.

tributary
A small river that joins the main river channel.

watershed
The place that divides two river basins.

# data[].attributes.body
Upper course features
As the river erodes the landscape in the upper course, it winds and bends to avoid areas of hard rock. This creates interlocking spurs, which look a bit like the interlocking parts of a zip.
When a river runs over alternating layers of hard and soft rock, rapids and waterfalls may form.

# data[].attributes.body
River landforms can be divided into upper, middle and lower course features. These include steep V-shaped valleys, oxbow lakes and flood plains, respectively.

Upper course features
Upper course river features include steep-sided V-shaped valleys, interlocking spurs, rapids, waterfalls and gorges.

Middle course river features include wider, shallower valleys, meanders, and oxbow lakes.

Lower course river features include wide flat-bottomed valleys, floodplains and deltas.

As the river moves through the upper course, it cuts downwards. The gradient here is steep and the river channel is narrow. Vertical erosion in this highland part of the river helps to create steep-sided V-shaped valleys, interlocking spurs, rapids, waterfalls and gorges.

Upper course river features👇👇

# data[].attributes.body
Meanders

In the middle course the river has more energy and a high volume of water. The gradient here is gentle and lateral (sideways) erosion has widened the river channel. The river channel has also deepened. A larger river channel means there is less friction, so the water flows faster:

As the river erodes laterally, to the right side then the left side, it forms large bends, and then horseshoe-like loops called meanders.

The formation of meanders is due to both deposition and erosion and meanders gradually migrate downstream.

The force of the water erodes and undercuts the river bank on the outside of the bend where water flow has most energy due to decreased friction.

On the inside of the bend, where the river flow is slower, material is deposited, as there is more friction.

Over time the horseshoe become tighter, until the ends become very close together. As the river breaks through, eg during a flood when the river has a higher discharge and more energy, and the ends join, the loop is cut-off from the main channel. The cut-off loop is called an oxbow lake.

A meander and oxbow lake in the Amazon👇

# data[].attributes.body
In the lower course, the river has a high volume and a large discharge. The river channel is now deep and wide and the landscape around it is flat. However, as a river reaches the end of its journey, energy levels are low and deposition takes place.

Floodplains

The river now has a wide floodplain. A floodplain is the area around a river that is covered in times of flood. A floodplain is a very fertile area due to the rich alluvium deposited by floodwaters. This makes floodplains a good place for agriculture. A build up of alluvium on the banks of a river can create levees, which raise the river bank.

Deltas

Deltas are found at the mouth of large rivers - for example, the Mississippi. A delta is formed when the river deposits its material faster than the sea can remove it. There are three main types of delta, named after the shape they create.

Arcuate or fan-shaped - the land around the river mouth arches out into the sea and the river splits many times on the way to the sea, creating a fan effect.

Key words
alluvium
The sediment deposited by rivers. Also known as silt.

levee
Ridges or banks formed by deposits of alluvium left behind by the periodic flooding of rivers. Can also be artificially constructed banks or walls.

# data[].attributes.body
The Slave Trade Abolition Act of 1807 banned the buying and selling of slaves.

The Slavery Abolition Act of 1833 abolished slavery completely in the British Empire.

# data[].attributes.body
Choose the correct option:

1. What does the water cycle show?

How water moves around between the atmosphere, oceans, rivers and land

How water gets into our homes

How waste water is purified so that it's safe to drink

2. What process occurs when water changes from a gas to a liquid?

Evaporation

Condensation

Precipiation

3. What is transpiration?

The transfer of water from lakes to the air

The transfer of water from plants into vapour in the air

The transfer of vapour from the air into clouds

4. Which type of flow is also called a river?

Surface run-off

Throughflow

Percolation

5. What does the process of interception do?

It slows down or prevents some water flowing back to the river

It stops water completely so it is lost from the system

It stores water in ice caps

6. Which of these is a store within the water cycle?

Precipitation

Evaporation

Ice caps

7. What is a river basin?

An area that a river flows into

An area drained by a river

The area outside the watershed

8. What is the watershed?

The edge of a drainage basin

A smaller river that flows into a larger river

The point where two rivers join together

9. What is the start of a river called?

The mouth

The watershed

The source

10. Where are you likely to find a delta?

In the upper section of the river

In the middle section of the river

In the lower section of the river

# data[].attributes.body
The triangular trade

The slave trade began with Portuguese (and some Spanish) traders, taking mainly West African (but some Central African) slaves to the American colonies they had conquered in the 15th century. British sailors became involved in the trade in the 16th century and their involvement increased in the 18th century when the Treaty of Utrecht (1713) gave them the right to sell slaves in the Spanish Empire. The slave trade made a great deal of profit for those who sold and exchanged slaves. Therefore, they often ignored the fact it was inhuman and unfair.

At least 12 million Africans were taken to the Americas as slaves between 1532 and 1832 and at least a third of them in British ships.

For the British slave traders it was a three-legged journey called the 'triangular trade':

West African slaves were exchanged for trade goods such as brandy and guns.

Slaves were then taken via the ‘Middle Passage’ across the Atlantic for sale in the West Indies and North America.

Finally, a cargo of rum and sugar taken from the colonies, was taken back to England to sell.

# data[].attributes.body
In the 16th and 17th centuries, Portuguese traders took slaves from Africa to work in the Portuguese colony of Brazil and the Spanish colonies of South America. As many as 350,000 Africans were taken in this way as slaves to the Americas.

In the 16th century, English pirates started selling slaves to the Spanish colonies. Sir John Hawkins was the first English sea-captain to do this, starting in 1562.

In 1625, the British captured Barbados in the West Indies and in 1655 they secured Jamaica. English slave traders started supplying African slaves to the English colonies.

In 1672, the Royal African Company was set up to trade African slaves to the sugar plantations of the West Indies.

In 1713, Spain gave British slave traders the contract, known as the Asiento, to trade 144,000 slaves a year to Spanish South America. This contract was part of the Treaty of Utrecht.l

# data[].attributes.body
After 1700, the numbers of slaves being transported increased greatly. Perhaps 8.5 million Africans were taken as slaves to the Americas.

A British slave ship set off from Liverpool, Glasgow or Bristol, carrying trade goods and sailed to West Africa.

Some slaves were captured directly by the British traders. They ambushed and captured local people in Africa.

Most slave ships got their slaves from British 'factors', who lived full-time in Africa and bought slaves from local tribal chiefs. The chiefs would raid a rival village and sell their captured enemies as slaves.

In 1700, a slave cost about £3-worth of traded goods, eg cloth, guns, gunpowder and brandy.

The slaves were marched to the coast in chained lines called coffles, where they were held in prisons called 'factories'.

The slave ship then sailed across the Atlantic to the West Indies – this leg of the voyage was called the 'Middle Passage'.

In the West Indies the slaves were sold at an auction called a 'scramble'. Some were sent to 'seasoning camps' to be trained to obey, often using brutal methods.

The selling price of a slave in the West Indies in 1700 was £20, so there was a good profit to be had, which made the risks of long journeys and possible harsh weather worthwhile.

# data[].attributes.body
The water cycle

Understanding how the water cycle operates is key to understanding how rivers work. The water cycle is also known as the hydrological cycle. It is called a cycle because water continuously moves around the system. Rivers are part of this cycle. The illustration below shows how water changes state through the cycle. It can be a liquid, a vapour or a solid.

How does the water cycle work?

Energy from the Sun heats the surface of the Earth.

Water is evaporated from oceans, rivers, lakes, etc.

The warm, moist air rises because it is less dense.

Condensation occurs when water vapour is turned back into water droplets as it cools down. Clouds are formed.

Precipitation occurs as water droplets get bigger and heavier they begin to fall as rain, snow and sleet, etc.

When the precipitation reaches the surface, some falls directly into the sea but other water falls on land:

Some water is intercepted by vegetation. Some water may then slowly reach the ground. Some will evaporate from the surface of leaves or be taken up by the plant roots, and some of this water will eventually return to the air as vapour through the process of transpiration. This slows down or prevents some water flowing back to the river.

Some water flows across the surface of the ground - surface run-off. This happens when the surface doesn't allow water to penetrate. Surface run-off is more likely to occur if the ground is saturated with water or when the rock is impermeable. This water moves quickly to the river.

Some water infiltrates into the soil. This through flow moves more slowly back to the river than surface run-off.

Some water percolates deeper into the ground and is slowly transferred back to the river or sea.

Stores and transfers

The major stores of water are the ocean, ice caps, land and the atmosphere. The movement of water between these stores is called transfers.

Key words:
condensation
A change of state in which gas becomes liquid by cooling.

dense
Crowded closely together.

hydrological cycle
The continual movement of water between the rivers, oceans, atmosphere and land.

impermeable
A substance which fluids are unable to pass through.

intercept
To interrupt the movement of something, eg water is intercepted by the leaves of trees when it rains.

percolation
When water moves downwards through the soil.

precipitation
Moisture that falls from the air to the ground. Includes rain, snow, hail, sleet, drizzle, fog and mist.

saturated
Unable to contain any more liquid.

# data[].attributes.body
What causes a tsunami?
Most tsunamis are caused by earthquakes at destructive plate boundaries. Here, an oceanic plate is subducted into the mantle beneath a continental plate. This movement causes friction, which in turn causes the plates to stick. Energy accumulates, like that of a compressed spring. When the energy exceeds the friction, the plates snap back into position. This movement thrusts the water above causing a wave to form. The waves can travel large distances. When the waves reach shallower water the following happens:

▪the shallow water slows the wave
▪their height can increase by several metres
▪the waves get closer together

A sign that a tsunami is approaching a coast is water retreating. Shortly after this happens. the waves reach the shore. This is actually the trough of the wave following behind.

BBC.COM

# data[].attributes.body
When earthquakes occur at sea they can jolt the seabed upwards. This creates huge waves which move away from the epicenter in all directions. In the case of the Japanese earthquake the wave quickly travelled the 80 km to the coast at Sendai, the capital of Miyagi prefecture. As it approached the shoreline and the seabed became shallower, the wave rose to 10 meters high and swept over the coastal defences.

Main impacts
Infrastructure

The waves travelled as far as 10 km inland in Sendai.

The tsunami flooded an area of approximately 561 square km.

Ports and airports in Sendai were damaged and closed.

The waves destroyed protective tsunami seawalls at several locations.

The massive surge destroyed three-storey buildings where people had gathered for safety.

A state of emergency was declared at the Fukushima nuclear power plant, where a cooling system failed and released radioactive materials into the environment.

In July 2013, TEPCO, the Tokyo Electric Power Company, admitted that about 300 tons of radioactive water continued to leak from the plant every day into the Pacific Ocean.

Social and economic

Four years after the quake, around 230,000 people who lost their homes were still living in temporary housing.

The total damages from the earthquake and tsunami are estimated at $300 billion dollars (about 25 trillion yen).

The number of confirmed deaths as of 10 April 2015 is 15,891. More than 2,500 people are still reported missing.

Responses to the disaster

The country recently unveiled a newly-installed, upgraded tsunami warning system.

Earthquake engineers examined the damage, looking for ways to construct buildings that are more resistant to quakes and tsunamis. Studies are ongoing.

BBC.CO.UK
IGCSE

# data[].attributes.headline
Measuring the power and strength of an earthquake

# data[].attributes.subject
Measuring the power and strength of an earthquake

# data[].attributes.body
The power of an earthquake is measured using a seismometer detects the vibrations caused by an earthquake. It plots these vibrations on a seismograph.

The strength, or magnitude, of an earthquake is measured using the Richter scale. The Richter scale is numbered 0-10 with 10 being the greatest strength or magnitude.

# data[].attributes.body
Japan is well prepared for earthquakes. It is located on a conservative plate boundary between the Eurasian, Pacific and Philippine plates and the country experiences about 20 per cent of the world's most serious seismic events.
The country was well prepared, therefore, for the huge earthquake of Friday 11 March 2011. At magnitude 9.1 on the Richter scale (which measures the intensity of an earthquake) it was the most powerful ever to hit Japan and the fifth strongest in the world history. The earthquake itself caused few deaths and there was relatively little damage. It did, however, produce a deadly tsunami which swept over the Japanese coastline, destroying buildings, roads and farmland. The wave washed people, houses, trucks and cars both inland and out to sea.

# data[].attributes.body
Earthquakes are caused by the movement of the Earth's plates.

What causes an earthquake?
An earthquake is the shaking and vibration of the Earth's crust due to movement of the Earth's plates (plate tectonics). Earthquakes can happen along any type of plate boundary.

Earthquakes occur when tension is released from inside the crust. Plates do not always move smoothly alongside each other and sometimes get stuck. When this happens pressure builds up. When this pressure is eventually released, an earthquake tends to occur.The point inside the crust where the pressure is released is called the focus. The point on the Earth's surface above the focus is called the epicentre.
Earthquake energy is released in seismic waves. These waves spread out from the focus. The waves are felt most strongly at the epicentre, becoming less strong as they travel further away. The most severe damage caused by an earthquake will happen close to the epicentre.
BBC.COM
IGCSE

# data[].attributes.body
Answer the following questions:

1. What is an earthquake?

The sudden and brief period of intense ground shaking

Where magma is erupted from the earth

The movement of earth's plates creating new land

2. At which plate margins do you find earthquakes?

Conservative and destructive

Constructive and destructive

All three plate margins

3. What is the point in the Earth's crust where the earthquake originates known as?

Epicentre

Focus

Shock waves

4. What is the point on the Earth's surface directly above where the earthquake originates?

Epicentre

Focus

Shock waves

5. What piece of equipment measures earthquakes?

Seismometer

Richter Scale

Mercalli Scale

6. What is an example of a short-term response?

Water and powerlines are disrupted

Aid from other countries

New homes are built to cope with earthquakes

7. What is earthquake prediction?

Constructing buildings so they are safe

Attempts to forecast an earthquake

Organising activities so people know what to do in an earthquake

8. How do people prepare for earthquakes?

They can watch the TV to see the earthquake forecast

They can't do anything; people just hope they don’t happen

Have drills and educate people on what to do in the event of an earthquake

# data[].attributes.body
Collision zones
Collision zones form when two continental plates collide. Neither plate is forced under the other, and so both are forced up and form fold mountains.

# data[].attributes.body
Heat from the core causes convection currents in the mantle. These currents slowly move the crust around. In some places the crust is destroyed. In other places new crust is formed.

Earthquakes and volcanoes are primarily found at plate boundaries. The plates are like giant rafts that slowly move around. Their movement is driven by convection currents in the mantle. The mantle is much hotter than the crust and its rock is molten. At the boundaries between plates, molten magma is able to force its way to the surface and escape as lava.

www.bbc.co.uk
KS3

# data[].attributes.body
Constructive plate boundary
A constructive plate boundary, sometimes called a divergent plate, occurs when plates move apart. Volcanoes are formed as magma wells up to fill the gap, and eventually new crust is formed.

# data[].attributes.body
There are different types of plate boundary.

Destructive plate boundary
A destructive plate boundary is sometimes called a convergent or tensional plate margin. This occurs when oceanic and continental plates move together. The oceanic plate is forced under the lighter continental plate. Friction causes melting of the oceanic plate and may trigger earthquakes. Magma rises up through cracks and erupts onto the surface.

# data[].attributes.body
Conservative plate boundary
A conservative plate boundary, sometimes called a transform plate, occurs where plates slide past each other in opposite directions, or in the same direction but at different speeds.

Friction is eventually overcome and the plates slip past in a sudden movement. The shockwaves created produce an earthquake

# data[].attributes.body
The Earth has four main layers - the inner core, the outer core, the mantle and the crust.

The crust is the thinnest layer, it can be classified into Oceanic crust and Continental crust.
The oceanic crust is the crust beneath the ocean, is only about 5 km thick.
The continental crust can be as thick as 35 km.

The mantle is a semi-liquid layer of magma or molten rock that moves due to convection currents.

The outer core is 2,000 km thick and is a liquid.

The inner core is 5,500°C - extremely hot. It is a very dense solid made from iron and nickel.

BBC

# data[].attributes.body
Volcanoes

Shield volcanoes are low with sloping sides and built of very thin lava and have gentle eruptions.
Strato-volcanoes can be quite dangerous and pose a threat to nearby communities. Strato-volcanoes have layers of ash and lava and have a violent eruptions and spewing superhot ash and gas at high speed.
Moreover, the difference is the viscosity of the lava. The viscosity of a liquid is a measure of its stiffness, or resistence to flow.
Low-viscosity lavas flow easily, erupt non-violently, and form gently-sloping shield volcanoes.
High-viscosity lavas do not flow easily. Pressure builds up within the magma chamber and eruptions are explosive and violent. High-viscosity lavas form steep-sided stratovolcanoes.
☆ Shield volcanoes have low viscosity lavas.
☆ Strato volcanoes have high viscosity lavas.

# data[].attributes.body
Bromo Tengger
Semeru National Park on the island of Java, Indonesia, is home to several active volcanoes, which can be seen here smoking ominously against a blue sky.

National Geographic
Photograph by Manamana

# data[].attributes.body
The Ring of Fire, also referred to as the Circum-Pacific Belt, is a path along the Pacific Ocean characterized by active volcanoes and frequent earthquakes. The majority of Earth’s volcanoes and earthquakes take place along the Ring of Fire.

National Geographic

# data[].attributes.body
Watch this video

# data[].attributes.body
Geography
Draw an annotated diagram showing the structure of the Earth. Add labels showing the crust, mantle and outer and inner cores.

# data[].attributes.body
The crust
This is the outside layer of the earth and is made of solid rock.There are two types of crust; oceanic and continental. Oceanic crust is denser and thinner and mainly com​posed of basalt.  Continental crust is less dense, thicker, and mainly composed of granite.

The mantle
The mantle lies below the crust and is up to 2900 km thick.  It consists of hot, dense, iron and magnesium-rich solid rock.

The core
The core is the center of the earth and is made up of two parts: the liquid outer core and solid inner core. The outer core is made of nickel, iron and molten rock. Temperatures here can reach up to 50,000 C.

# data[].attributes.body
A volcano is an opening in the structure of the surface of the Earth from which hot magma flows out.

Volcanoes have long shafts that go all the way down through the Earth’s first layer, the crust, to magma in between the crust and the mantle (the Earth’s second layer). It’s so hot there that rocks melt into liquid! This is called magma.

The structural features of a volcano
Vent: It's an opening from which hot magma flow out to the surface of the Earth.
Crater: It's a bowl shaped like opening or a mouth of a volcano.
Magma chamber: It's here that the hot magma is stored beneath a volcano.
Magma: It's the hot molten fluid, which comes out to the surface during a volcanic eruption.
Lava: when molten magma reaches the surface of the Earth, it's known as Lava.

☆ Many volcanoes are mountains, made up of layers of lava and ash.

Data Bank
▪The largest active volcano in the world is Mauna Loa, on the Hawaiian islands.
▪Ash from volcanoes is very good for growing things. It adds nutrients to the soil.
▪Most volcanoes can be found in countries that have coastlines on the Pacific Ocean – this is called the Ring of Fire.
▪Some volcanoes are underwater!
▪The largest volcano in Europe is Mount Etna in Sicily (Italy).