About three-quarters of the electricity generated in the UK comes from power stations fuelled by fossil fuels. This diagram shows an energy transfer diagram for the generation of electricity from a fossil fuel such as coal.

Fossil fuels are non-renewable because they will run out one day. Burning fossil fuels generates greenhouse gases and relying on them for energy generation is unsustainable. Hence the need to find more renewable, sustainable ways of generating energy.

Renewable or infinite energy resources are sources of power that quickly replenish themselves and can be used again and again.

Where it is from?
Formed from fossilised plants and consists of carbon with organic and inorganic compounds. It is mined from seams of coal found between layers of rock in the earth.
Advantages
Coal is a ready-made fuel which is cheap to mine and convert to electricity – it lasts longer than oil or gas.
Disadvantages
When burned, coal gives off atmospheric pollutants, including greenhouse gases.

2. Oil (fossil fuel)
Where it is from?
Carbon-based liquid formed from fossilised animals. Lakes of oil are found between seams of rock in the earth.
Advantages
Oil is a ready-made fuel which is cheap to extract and convert into energy. It is used in industry and transport.
Disadvantages
When burned, oil gives off atmospheric pollutants, including greenhouse gases. There is a limited supply of oil.

3. Natural gas (fossil fuel)
Where it is from?
Methane and other gases trapped between seams of rock under the earth are released through pipes sunk into the ground.
Advantages
Gas is a ready-made fuel and relatively cheap. It is used in houses for heating and cooking and is a slightly cleaner fuel than coal and oil.
Disadvantages
When burned, it gives off atmospheric pollutants, including greenhouse gases. There is a limited supply of gas.

4. Nuclear
Where it is from?
Radioactive minerals such as uranium are mined. Electricity is generated from the energy that is released when atoms from these mineral split.
Advantages
A small amount of radioactive material produces a lot of energy, it’s relatively cheap and can last a long time. It doesn’t give off pollutants.
Disadvantages
Nuclear reactors are expensive to run and nuclear waste is highly toxic. Leakage of nuclear materials can have a devastating impact on people and the environment.

5. Biomass
Where it is from?
It is generated from decaying plant or animal waste, or organic material and can be burned to provide energy.
Advantages
It is a cheap and readily available source of energy. If crops are replaced, it can be a long-term, sustainable energy source.
Disadvantages
When burned, it gives off atmospheric pollutants, including greenhouse gases.

6. Wood
Where ot is from?
Obtained from felling trees, burned to generate heat and light.
Advantages
A cheap and readily available source of energy. If trees are replaced, wood burning can be a long term sustainable energy source.
Disadvantages
When burned, it gives off atmospheric pollutants, including greenhouse gases.

How long will fossil fuels last?
Estimates from international organisations suggest that if the world's demand for energy from fossil fuels continues at the present rate that oil and gas reserves may run out within some of our lifetimes. Coal is expected to last longer.

Fossil fuel: Oil
Time left: 50 years

Fossil fuel: Natural gas
Time left: 70 years

Fossil fuel: Coal
Time left: 250 years

Key words:
fossil fuel
Natural, finite fuel formed from the remains of living organisms, eg oil, coal and natural gas.

greenhouse gas
The gases responsible for global warming - carbon dioxide, methane, nitrous oxide and CFCs (chlorofluorocarbons).

non-renewable
A resource that cannot be replaced when it is used up, such as oil, natural gas or coal.

renewable
Energy sources that are replenished and not exhausted, eg solar power.

unsustainable
Resources which cannot be used forever and cannot be replaced or recycled after they are used. The use of fossil fuels is unsustainable, for example.

Watch this video👇👇

Renewable energy sources quickly replenish themselves and can be used again and again. For this reason they are sometimes called infinite energy resources.

Types of energy
1. Solar
Where it is from?
Energy from sunlight is captured in solar panels and converted into electricity.
Advantages
Potentially infinite energy supply. Single dwellings can have own electricity supply.
Disadvantaged
Manufacture and implementation of solar panels can be costly.

2. Wind
Where it is from?
Wind turbines (modern windmills) turn wind energy into electricity.
Advantaged
Can be found singularly, but usually many together in wind farms. Wind is a potentially infinite energy supply.
Disadvantages
Manufacture and implementation of wind farms can be costly. Some local people object to on-shore wind farms, arguing that it spoils the countryside.

3. Geothermal
Where it is from?
In volcanic regions it is possible to use the natural heat of the earth. Cold water is pumped under ground and comes out as steam. Steam can be used for heating or to power turbines creating electricity.
Advantages
Potentially infinite energy supply. Used successfully in some countries, such as New Zealand and Iceland.
Disadvantages
Can be expensive to set up and only works in areas of volcanic activity. Geothermal and volcanic activity might calm down, leaving power stations redundant. Dangerous elements found underground must be disposed of carefully.

4. Hydrological or Hydroelectric Power (HEP)
Where it is from?
Energy harnessed from the movement of water through rivers, lakes and dams.
Advantages
Creates water reserves as well as energy supplies.
Disadvantages
Costly to build. Can cause the flooding of surrounding communities and landscapes. Dams have major ecological impacts on local hydrology.

5. Biomass
Where it is from?
It is generated from decaying plant or animal waste, or organic material and can be burned to provide energy.
Advantages
It is a cheap and readily available source of energy. If crops are replaced, it can be a long-term, sustainable energy source.
Disadvantages
When burned, it gives off atmospheric pollutants, including greenhouse gases.
 

Make sure you know what types of energy are renewable and non-renewable. It is important to remember that biomass and wood are only renewable if the trees and crops are replanted. Many people fall into the trap of thinking that bio means renewable - it doesn't!

Different countries have different amounts of water. Generally speaking:

Water consumption has been rising globally over time. There are two main reasons for this:

Everyone needs water in order to survive. Water makes up at least 60% of a person’s bodyweight and it is needed for all bodily functions. People also use water for hygiene, cooking and cleaning. The population of the world is increasing, but there is only a fixed amount of fresh water available for us to use.

As countries develop, their water use increases. People in wealthier nations have water delivered into their homes via pipeline. Modern appliances, such as dishwashers and washing machines, use a lot of water. Commercial agriculture, industry and tourism in high income countries (HICs) consume vast quantities of water too. The water footprint of HICs is much higher than low income countries (LICs). As more countries develop, the demands on water will increase.

Key words
aquifer

Naturally occurring underground water stores.

ecosystem
A community of animals, plants and microorganisms, together with the habitat where they live.

Equator
The line around the centre of the Earth, parallel to the Tropics of Cancer and Capricorn.

high income country (HIC)
A country with a gross national income per capita above US $12,735 (according to the World Bank) such as the Netherlands and the UK.

hygiene
Cleanliness.

infrastructure
The basic structures needed for an area to function, for example roads and communications.

latitude
Imaginary lines around the Earth running parallel to the equator. These are measured in degrees north or south of the equator.

low income country (LIC)
Based on the World Bank's income classifications, a LIC has a gross national income (GNI per capita) of $1,045 or lower.

A lack of available water for everyone.

The Earth's average temperature has changed over the last 500,000 years. There have been times when it has been warmer than it is at present (interglacial phases) and times when it has been cooler (glacial phases), when there have been ice ages.

Evidence of global warming
Evidence has shown that the Earth’s temperature is rising, and that an increase in greenhouse gases in the atmosphere is responsible. This will continue to create a number of negative and positive effects.

1. Thermometer readings

On-going temperature recordings using thermometers have shown a clear warming of the Earth's temperature over the past few decades. By using this data, scientists have seen an average combined land and ocean surface temperature increase of 0.85°C since the end of the 19th century. In the northern hemisphere, the period between 1983 and 2012 was the warmest 30-year period of the last 1,400 years.

The degree to which the climate warms in the future will depend on natural climate variability and the level of greenhouse gas emissions. If greenhouse gas emissions continue, average global temperatures will rise. However, some regions such as the Arctic will warm faster than others.

Over the past 50 to 100 years, photographic evidence has shown that the world's glaciers have been melting, which has caused them to retreat. The melting of glaciers around the world has been observed since the late 1800s. The rise in global temperatures is causing glaciers to disappear and is increasing the melting of sea-ice in the Arctic. Artic sea-ice is disappearing at a rate of 10 per cent every decade.

In recent years there have been signs of a seasonal shift in many regions of the world. In the UK spring arrives earlier and winters tend to be less severe. These seasonal changes affect the nesting and migration patterns of wildlife.

Between 1901 and 2010, average global sea levels rose by 0.19 metres.

Key words 😊
climate change
The long-term alteration of weather patterns.

desalination
The removal of salt from water. This is an energy-intensive process. Also known as desalinisation.

desertification
The spread of desert conditions in arid regions due to human activities, drought or climate change.

glacier
A mass of snow and ice which moves slowly under the weight of gravity

global warming
The rise in the average temperature of the Earth's surface.

greenhouse effect
The retention of heat in the atmosphere caused by the build-up of greenhouse gases.

greenhouse gas
The gases responsible for global warming - carbon dioxide, methane, nitrous oxide and CFCs (chlorofluorocarbons).

honeypot site
A popular visitor attraction or area, where large numbers of people visit.

Some human activities increase the greenhouse gases in the atmosphere:

Greenhouse gases = are produced naturally and trap heat in the Earth's atmosphere like a blanket. 

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.

2. Antarctica has a high albedo. What does this mean?

3. How do icebergs form?

4. How have scientists in Antarctica been able to study the climate of the past?

5. Why are scientists concerned about the thinning of the ice sheets in Antarctica?

6. What does the ozone layer do?

7. Which chemicals have been linked with ozone depletion?

8. Where is the area of damaged ozone?

9. Which of the following words could describe Antarctica?

Antarctica can be called a desert because of the low levels of precipitation. Antarctica has the coldest land temperature recorded on the Earth of -89.2°C. The average annual temperature is around -50°C.

The precipitation in Antarctica is mainly snow. In coastal regions about 200 mm can fall annually. In mountainous regions and on the East Antarctica plateau the amount is less than 50 mm annually. This is not as high as other desert regions because it is so cold, so the snow gradually builds up year after year. There are also strong winds, with recordings of up to 200 mph being made.

Why is it so cold and dry?

The ice in Antarctica
The ice in Antarctica is on average 2.5 km thick. Nearly 99 per cent of Antarctica is covered by an ice sheet. The ice sheet moves by gravity downhill. A few mountain peaks may be seen above the ice sheet. These are called Nunataks.

Glossary
albedo
A measure of how much sunlight a surface reflects.

atmosphere
The layers of gases that surround the Earth. The important gases in the atmosphere are nitrogen, oxygen and carbon dioxide.

chlorofluorocarbon (CFC)
An organic compound.

crevasse
Deep crack in a glacier or ice sheet.

glacier
A slow-moving ice mass, formed over a long period from compacted snow.

ice sheet
A large, permanent area of ice which could expand in most directions.

ice shelf
An area of ice which extends beyond land and floats over water.

iceberg
A large mass of ice that floats on the sea.

ozone layer
A layer of gas in the atmosphere that protects the Earth from harmful radiation from the Sun.

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