The climate has always changed, but the current rate of warming is caused by human activity.
📉 Evidence and causes
Natural causes of past change include Milankovitch cycles (orbit changes), volcanic eruptions and solar output. The evidence for human-caused warming: ice cores show CO₂ now far above 800 000 years of natural levels; each of the past four decades has been warmer than the last; ocean heat, sea level and glacier loss are rising. Anthropogenic causes: burning fossil fuels, deforestation, agriculture (methane from cattle and rice) and cement.
CO₂ range in ice cores: 180–300 ppm
CO₂ today: ~420 ppm
sea level rise since 1900: about 20 cm
rate now: about 4 mm a year
🖼️ See it
The rapid warming since 1950 is explained by human causes; the natural causes alone cannot account for it.
🌍 Impacts and responses
Impacts: sea level rise, more extreme weather, ecosystem change (coral bleaching), threats to food and water, and climate refugees. Responses: mitigation (renewables, energy efficiency, carbon capture, reforestation, carbon taxes) and adaptation (flood defences, drought-resistant crops). The Paris Agreement relies on national pledges (NDCs). The poorest countries have emitted least but suffer most.
4 mm/year × 50 years = 200 mm = 20 cm
net zero: emissions balanced by removal
target: net zero around 2050 for 1.5 °C
Climate justice: those who contribute least to the problem often face the greatest risks.
✏️ Quick check · 1 of 7
Anthropogenic
Anthropogenic means caused by:
People.
✏️ Quick check · 2 of 7
Evidence
Ice cores help scientists by:
Ancient air.
✏️ Quick check · 3 of 7
Net zero
Net zero emissions means:
Balance.
✏️ Quick check · 4 of 7
NDC
In the Paris Agreement, NDCs are:
Pledges.
✍️ Type your answer · 5 of 7
Sea level rises 4 mm a year.
How many mm does it rise in 50 years?
Enter an exact answer, without rounding.
mm
Multiply.
✍️ Type your answer · 6 of 7
CO₂ was 280 ppm before industry and is 420 ppm now.
What percentage increase is this?
Enter an exact answer, without rounding.
%
Increase ÷ original × 100.
✍️ Type your answer · 7 of 7
A tree absorbs about 22 kg of CO₂ a year.
How many trees absorb 2200 kg a year?
Enter an exact answer, without rounding.
Divide.
📝 Lesson quiz · 5 questions
0 / 5
Re-read the lesson, then give it another go.
Question 1 of 5
Which is a greenhouse gas besides CO₂?
Question 2 of 5
Coral bleaching is caused mainly by:
Question 3 of 5
A carbon tax:
Question 4 of 5
Natural causes of climate change include:
Question 5 of 5
Which is an adaptation measure?
Lesson 2 · Economic geography
⚡ Energy & Resources
Energy demand is rising worldwide. How the energy mix changes will shape both the economy and the climate.
🛢️ The energy mix
World primary energy comes from oil (about 31%), coal (27%), natural gas (23%), with the rest from hydro, nuclear and renewables. Energy security depends on diverse supplies and domestic production; many countries import fuel. Energy intensity is energy used per unit of GDP. Costs of solar and wind have fallen by over 80% in a decade.
oil 31% + coal 27% + gas 23% = 81% fossil fuels
remainder: 100 − 81 = 19%
UK: coal was 40% of electricity in 2012, under 2% by 2020
🖼️ See it
About four fifths of the world’s energy still comes from fossil fuels, which is why the shift to renewables matters for climate change.
🌬️ Renewables and trade-offs
Every source has costs. Wind and solar are clean but intermittent, so need storage or backup. Hydropower is reliable but floods land (Three Gorges Dam displaced about 1.3 million people). Nuclear produces low-carbon power but creates radioactive waste. Biofuels may compete with food crops. A balanced energy plan considers cost, reliability, emissions and local impacts.
capacity factor: share of the maximum output actually delivered
wind 35%, solar 25%, nuclear 90%
1000 MW wind farm at 35% = 350 MW average
Capacity is not output. A 100 MW solar farm rarely produces 100 MW all day.
✏️ Quick check · 1 of 7
Energy security
Energy security means:
Dependable.
✏️ Quick check · 2 of 7
Intermittent
Wind and solar are intermittent because:
Not constant.
✏️ Quick check · 3 of 7
Nuclear
A drawback of nuclear power is:
Waste.
✏️ Quick check · 4 of 7
Hydro
A major local impact of large dams is:
Reservoirs.
✍️ Type your answer · 5 of 7
Oil is 31%, coal 27% and gas 23% of world energy.
What percentage is fossil fuel in total?
Enter an exact answer, without rounding.
%
Add.
✍️ Type your answer · 6 of 7
A wind farm has a capacity of 1000 MW and a capacity factor of 35%.
What is its average output, in MW?
Enter an exact answer, without rounding.
MW
35% of 1000.
✍️ Type your answer · 7 of 7
A household uses 3600 kWh a year and pays 0.2 per kWh.
What is the annual bill?
Enter an exact answer, without rounding.
Multiply.
📝 Lesson quiz · 5 questions
0 / 5
Re-read the lesson, then give it another go.
Question 1 of 5
Which has the highest capacity factor?
Question 2 of 5
Biofuels can create a problem because:
Question 3 of 5
Energy efficiency means:
Question 4 of 5
Which statement about coal is true?
Question 5 of 5
Why are energy mixes shifting?
Lesson 3 · Economic geography
🚢 Trade & Globalisation
Goods, money and information cross the globe. Geography explains who gains and who loses.
📦 Global supply chains
Globalisation links economies through trade, investment and migration. Transnational corporations (TNCs) locate design, manufacture and assembly where it is cheapest or most effective; a smartphone has parts from dozens of countries. Containerisation cut shipping costs dramatically. About 90% of world trade goes by sea. Free trade removes tariffs; trading blocs include the EU and USMCA.
TNC: Apple, Toyota, Unilever
tariff: a tax on imports
10% tariff on a $200 good = $20
🖼️ See it
Globalisation lets each step happen where it is cheapest, linking workers and shoppers on different continents.
⚖️ Winners and losers
Globalisation has helped NEEs such as China, Vietnam and India grow quickly and has lowered consumer prices. But deindustrialisation has hit manufacturing regions in HICs, and low-skilled workers in some countries face exploitation. The Rana Plaza factory collapse (Bangladesh, 2013, over 1100 deaths) highlighted working conditions. TNCs can bring jobs and technology to host countries but may also take profits abroad.
Bangladesh garments: ~85% of exports
China’s share of world manufacturing: ~30%
change: more jobs in exporting countries, fewer in some HIC regions
Both sides of an argument matter. Globalisation lifted millions out of poverty yet widened inequality in many places.
✏️ Quick check · 1 of 7
TNC
A TNC is a:
Big global firm.
✏️ Quick check · 2 of 7
Tariff
A tariff is a:
Import tax.
✏️ Quick check · 3 of 7
Deindustrialisation
Deindustrialisation means:
Factories closing.
✏️ Quick check · 4 of 7
Container
Containerisation lowered the cost of:
Boxes.
✍️ Type your answer · 5 of 7
A 10% tariff is applied to a good that costs $200.
How much tariff is paid, in $?
Enter an exact answer, without rounding.
$
10% of 200.
✍️ Type your answer · 6 of 7
About 90% of world trade is by sea. World trade is 22 billion tonnes.
About how many billion tonnes go by sea?
Enter an exact answer, without rounding.
billion t
90% of 22.
✍️ Type your answer · 7 of 7
Rana Plaza killed over 1100 workers in 2013. Brands signed the International Accord on factory safety in 2021.
How many years after the collapse was that?
Enter an exact answer, without rounding.
years
Subtract.
📝 Lesson quiz · 5 questions
0 / 5
Re-read the lesson, then give it another go.
Question 1 of 5
A trading bloc is:
Question 2 of 5
A benefit for countries hosting a TNC is:
Question 3 of 5
An NEE is a:
Question 4 of 5
Sweatshop labour refers to:
Question 5 of 5
Free trade means:
Lesson 4 · Human geography
🏗️ Urban Challenges & Planning
Case studies of real cities show how geography, economy and planning meet.
🌆 Lagos and London
Lagos (Nigeria), with over 15 million people, grows by roughly 3–4% a year; its challenges include slums (Makoko), traffic, flooding and informal jobs. Government initiatives include Bus Rapid Transit and slum upgrading. London shows regeneration: the former docklands became Canary Wharf and the 2012 Olympic Park, while challenges include housing costs and congestion (the congestion charge began in 2003).
Lagos: ~15 million, rapid growth
London: ~9 million, regeneration
congestion charge: reduces traffic in central London
🖼️ See it
Land is most expensive in the centre, so buildings are taller and denser there.
📐 Planning sustainable cities
Sustainable cities use public transport, cycling, green space, efficient buildings, recycling and flood control. Planners use zoning (residential, industrial, commercial areas) and green belts to limit sprawl. The 15-minute city idea puts daily needs within a short walk or cycle. Smart cities use sensors and data to manage traffic and energy.
zoning: separate land uses
green belt: protected land around a city
15-minute city: everything needed within a 15-minute walk or cycle
Good planning improves life quality by reducing commute time, pollution and cost.
✏️ Quick check · 1 of 7
Regeneration
London’s Docklands is an example of:
Renewal.
✏️ Quick check · 2 of 7
Congestion charge
The London congestion charge aims to:
Less traffic.
✏️ Quick check · 3 of 7
Green belt
A green belt:
Planning tool.
✏️ Quick check · 4 of 7
15-minute city
A 15-minute city means:
Walkable.
✍️ Type your answer · 5 of 7
Lagos has 15 million people and grows by 4% a year.
How many people are added in one year, in thousands?
Enter an exact answer, without rounding.
thousand
4% of 15 million.
✍️ Type your answer · 6 of 7
A commuter saves 25 minutes each way by taking a new train line.
How many minutes a day does that save?
Enter an exact answer, without rounding.
min
Both directions.
✍️ Type your answer · 7 of 7
A city has 120 km² of land and 30% is green space.
How many km² is green space?
Enter an exact answer, without rounding.
km²
30% of 120.
📝 Lesson quiz · 5 questions
0 / 5
Re-read the lesson, then give it another go.
Question 1 of 5
Makoko is a:
Question 2 of 5
Zoning means:
Question 3 of 5
A smart city uses:
Question 4 of 5
Urban sprawl is:
Question 5 of 5
Which would reduce a city’s carbon footprint?
Lesson 5 · Skills
🧮 Geographical Skills & Fieldwork
Geographers collect data, present it and draw conclusions. Good enquiry rests on a clear question, sound methods and honest evaluation.
🔬 Fieldwork enquiry
A fieldwork enquiry has stages: question (for example, “How does river velocity change downstream?”), hypothesis, methods, data collection, presentation, analysis, conclusion and evaluation. Sampling can be random, systematic (every nth) or stratified (in proportion to groups). Reliable data come from repeating measurements.
velocity = distance / time
5 m in 10 s → 0.5 m/s
three repeats: 0.5, 0.6, 0.4 → mean = 1.5 / 3 = 0.5 m/s
🖼️ See it
Fieldwork follows these steps. Repeat measurements and sample fairly so the results can be trusted.
📊 Data and graphs
Choose the right graph: bar chart for categories, line graph for change over time, scatter graph for relationships (with a line of best fit), pie chart for proportions, choropleth map for shaded regions. Summarise data with mean, median, mode and range. A correlation is not proof of causation. Evaluate limitations: small sample, bias, time of year, weather.
data: 2, 4, 4, 6, 9
mean = 25 / 5 = 5; median = 4; mode = 4; range = 9 − 2 = 7
Correlation does not prove cause. Ice-cream sales and drownings both rise in summer, yet ice cream does not cause drowning.
✏️ Quick check · 1 of 7
Graph choice
To show change over time you would use a:
Trend.
✏️ Quick check · 2 of 7
Random sampling
Random sampling helps avoid:
Fair selection.
✏️ Quick check · 3 of 7
Scatter
A scatter graph shows:
Pairs of values.
✏️ Quick check · 4 of 7
Correlation
Correlation means:
Linked.
✍️ Type your answer · 5 of 7
Data: 2, 4, 4, 6, 9.
What is the mean?
Enter an exact answer, without rounding.
Add and divide by 5.
✍️ Type your answer · 6 of 7
Data: 2, 4, 4, 6, 9.
What is the range?
Enter an exact answer, without rounding.
Largest minus smallest.
✍️ Type your answer · 7 of 7
A float moves 12 m in 8 s.
What is the river velocity, in m/s?
Enter an exact answer, without rounding.
m/s
Distance ÷ time.
📝 Lesson quiz · 5 questions
0 / 5
Re-read the lesson, then give it another go.
Question 1 of 5
A hypothesis is:
Question 2 of 5
Which measure of average is not affected by extreme values?
Question 3 of 5
Stratified sampling:
Question 4 of 5
Evaluating fieldwork means:
Question 5 of 5
A choropleth map uses:
Final Challenge
🏆 10-Question Challenge Quiz
Questions from every topic in this course. Pick an answer for each one, then hit Check My Answers.
0 / 10
💪 Keep practicing — go back through the lessons and retake the quiz!
Q1 · Climate Change: Causes & Evidence
The strongest evidence that recent warming is human-caused is:
Q2 · Climate Change: Causes & Evidence
Which is an adaptation measure?
Q3 · Energy & Resources
The best energy strategy balances:
Q4 · Energy & Resources
Why are energy mixes shifting?
Q5 · Trade & Globalisation
Which is a benefit of globalisation for consumers?