Weather and Climate: KS3 Geography Explained

Weather is the state of the atmosphere at a specific place and time — sunny in Birmingham this afternoon. Climate is the average pattern of weather at a place over at least 30 years — the UK is temperate maritime.

What is the difference between weather and climate?

The simplest way to remember the distinction is this: weather is what you wear today; climate is what you put in your wardrobe. Weather changes hour by hour and day by day. Climate describes the long-term average and is measured over a minimum of 30 years — the standard period used by the Met Office and the World Meteorological Organisation.

| Weather | Climate
Timescale | Hours to days | 30+ years
Example | "Heavy rain in Manchester today" | "Manchester averages 800 mm of rain per year"
Measured by | Weather stations, satellites | Long-term averages from climate records
Changes | Quickly and unpredictably | Slowly (without human influence)

This distinction matters enormously in the context of climate change. When people say "climate change is not real because it snowed today," they are confusing a weather event (one cold day) with climate (long-term temperature trends). The Met Office's Central England Temperature record, which extends back to 1659, shows a clear warming trend across centuries — that is a climate signal, not a weather forecast.

What are the factors that affect climate?

Six main factors determine the climate of any given location. Geographers use the acronym HALTAC as a memory aid.

Factor | What it means | Example
Height (altitude) | Higher = colder (roughly 6.5 °C per 1,000 m) | Ben Nevis summit averages −0.5 °C; Fort William below averages 8 °C
Aspect | South-facing slopes receive more direct sunlight in the northern hemisphere | South-facing gardens are warmer for growing
Latitude | Closer to the equator = more intense solar radiation | UK at 50–60 °N is cooler than Spain at 36–44 °N
Terrain (continentality) | Distance from the sea — inland areas have more extreme temperatures | Moscow (continental): cold winters, hot summers; London (maritime): mild both
Air masses | Large bodies of air that carry characteristics from where they formed | Polar maritime air brings cold, wet weather to the UK
Currents (ocean) | Warm/cold ocean currents affect temperatures of coastal areas | The North Atlantic Drift keeps the UK warmer than its latitude predicts

What is the UK's climate?

The UK has a temperate maritime climate, characterised by mild winters, cool summers, and rainfall spread throughout the year. The Met Office defines "maritime" climates as those strongly influenced by the sea, which moderates temperature extremes in both directions.

Key features of the UK climate:

Average annual temperature: approximately 9 °C (ranging from about 5 °C in the Scottish Highlands to 11 °C in southern England)

Average annual rainfall: roughly 1,154 mm across the UK, but highly variable — the west receives far more than the east due to prevailing westerly winds bringing moisture from the Atlantic

Prevailing winds: south-westerly, bringing mild Atlantic air for most of the year

Seasons: four distinct seasons, though transitions are gradual rather than sharp

The North Atlantic Drift (a warm ocean current) is a key reason the UK is warmer than you might expect for its latitude: compare London (51.5 °N) with Calgary in Canada (51 °N), which has far harsher winters.

What are the global climate zones?

At KS3, students are expected to know the main climate zones and where they occur. The most widely used classification system was developed by Köppen and Geiger in the early twentieth century.

Climate zone | Characteristics | Example locations
Tropical | Hot (>18 °C every month), high rainfall | Amazon Basin, Central Africa
Arid (desert) | Very low rainfall (<250 mm/year), extreme temperatures | Sahara, Arabian Peninsula
Temperate | Mild temperatures, moderate rainfall | UK, western Europe, New Zealand
Continental | Hot summers, cold winters, lower rainfall | Russia, Canada, central USA
Polar | Extreme cold, very little precipitation (mostly snow) | Antarctica, Arctic regions
Mediterranean | Hot, dry summers; mild, wet winters | Southern Spain, Greece, California

Understanding climate zones is essential for KS3 geography because they help explain patterns of vegetation, biodiversity, human settlement, and economic activity across the world.

How does climate change affect weather patterns?

Climate change is altering the characteristics and frequency of weather events. The Met Office's State of the UK Climate report (published annually) documents measurable changes in the UK's observed climate, including:

The UK's ten warmest years on record have all occurred since 2002.

Average UK temperatures have risen by approximately 1 °C since pre-industrial times.

Heavy rainfall events are becoming more intense, increasing flood risk.

The number of very cold days (below freezing) has decreased.

These are climate trends — shifts in averages and frequencies — not individual weather events. The science distinguishes between climate change (the long-term shift) and weather attribution (the role climate change plays in making specific events more or less likely). This is an active area of research at institutions including the Met Office Hadley Centre.

Frequently asked questions

What is the difference between weather and climate?

Weather is the short-term state of the atmosphere at a specific place and time — temperature, rainfall, wind speed, cloud cover — which can change hour by hour. Climate is the long-term average of weather conditions over at least 30 years. The phrase often used is "climate is what you expect; weather is what you get."

What type of climate does the UK have?

The UK has a temperate maritime climate, strongly influenced by the Atlantic Ocean and the North Atlantic Drift current. This produces mild, wet winters, cool summers, and rainfall distributed throughout the year. There is significant regional variation: the west is wetter and slightly milder; the east is drier and experiences more temperature extremes.

Why does latitude affect climate?

Latitude determines the angle at which sunlight strikes the Earth's surface. Near the equator (low latitude), sunlight strikes at a steep angle, concentrating energy over a small area and producing high temperatures. Near the poles (high latitude), sunlight strikes at a shallow angle, spreading the same energy over a much larger area, producing lower temperatures. This is why the UK at 50–60 °N is cooler than tropical countries near 0°.

What does the term HALTAC mean in geography?

HALTAC is a memory aid for the six main factors that affect climate: Height (altitude), Aspect, Latitude, Terrain/continentality, Air masses, and Currents (ocean). Together these factors explain why two places at the same latitude can have very different climates — for example, why western Norway is far milder in winter than eastern Canada at the same latitude.

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