1. UK Climate is Temperature – Cool, Wet Winters and Warm, Wet Summers
Temperature in the UK varies with the seasons. It’s coldest in winter, it warms up through spring, is hottest in summer, and then cools down again through autumn.
Temperature ranges from an average of 5°C in January to 20°C in August.
Rainfall in the UK is fairly high all year round, but it also varies with the seasons. It’s higher in autumn and winter (an average of 120mm in January) and lower in spring and summer (an average of 65mm in May).
Winds in the UK are mostly warm south westerlies, but cold north winds are also common. Wind speed varies considerably by season – winds are generally stronger in autumn and winter than in spring and summer.

2. UK Climate is a Result of its Latitude and Location
LATITUDE – the UK is at mid-latitude (between 50 and 55°N). It doesn’t get very hot because the sun is never very high in the sky. It also doesn’t get very cold because there are several hours of daylight even in winter.
LOCATION IN RELATION TO ATMOSPHERIC CELLS – the UK is on the northern edge of a Ferrel Cell. Surface winds bring warm air from the south, and the warm air rises. This creates low pressure and causes depressions (low pressure weather systems), which bring rain throughout the whole year!
MARITIME LOCATION – the UK is surrounded by water, which gains and loses heat more slowly than the land does. This means there are cool winds blowing from the sea to the land in summer, and warm winds blowing form the sea to the land in winter. So , the summer is cooler and the winter is warmer than inland locations at the same latitude.
LOCATED NEAR THE GULF STREAM – this makes the UK warmer than places at the same latitude.

3. Climates Varies Within the UK
TEMPERATURE – its warmer in the south because there’s more isolation (more solar radiation reaching the ground). This is because the sun is higher in the sky and there are more hours of daylight than in the north. E.g. annual average maximum temperature is 13.6°C in Cornwall, and 9.3°C in the north of Scotland.

4. Climates Varies Within the UK
PRECIPITATION – its wetter in the west that the east, e.g. annual average rainfall is 871mm in Blackpool (on the west coast), and 565mm in Cleethorpes (on the east coast). This is because south westerly surface winds bring warm, wet air from the Atlantic Ocean. The air reaches the west side of the UK, and it’s forced upwards over the land. The air pools, the water vapour condenses and it rains. This is known as orographic or relief rainfall. The west of the UK is generally more mountainous than the east, so the air masses lose most of their moisture in the west. The area to the east of the mountains, where less rain falls, is called the rain shadow.

5. Climates Varies Within the UK
WIND
Winds are stronger in the west, e.g. the annual average wind speed is 21.7km/h in St. Mawgan (on the south west coast), and 16.7km/h in Marham (on the east coast). This is because south westerly surface winds come over the ocean – the ocean is flat so there’s nothing to slow the winds down. When the winds hit land, they’re affected by hills and they become weaker.
Winds are stronger at higher altitudes because there are fewer obstacles to slow them down.

6. There are Five Main Air Masses that Affect the UK
Air masses are large volumes of air with a similar temperature and water vapour content.
They cover large areas (several hundred km2) and can travel long distances.
They’re classified by the region they form over:
Arctic or Polar air masses form at high latitudes (so they’re cooler)
Tropical air masses form at low latitudes (so they’re warmer)
Maritime air masses form over oceans ( so they’re got a higher water vapour content)
Continental air masses form over land (so they’re got a lower water vapour content)
The UK is affected by five different air masses. Each air mass brings a different type of weather, which is one of the reasons why the UK’s weather is so variable.

7. The are Five Main Air Masses that Affect the UK

8. POLAR MARITIME air masses form over the North Atlantic Ocean
POLAR MARITIME air masses form over the North Atlantic Ocean. They bring cold weather and rain.
ARCTIC MARITIME air masses form over the Arctic Ocean. They bring very cold, wet air which causes cold weather and rain.
TROPICAL MARITIME air masses form over the Atlantic Ocean. They bring warm, wet air, which causes warm weather and rain.
POLAR CONTINENTAL air masses form over Siberia (in the Arctic). They bring cold, dry air which causes very cold, dry weather. These air masses can bring snow if the air picks up moisture from the North Sea.
TROPICAL CONTINENTAL air masses form over Africa. They bring warm, dry air which causes hot, dry weather.
Discuss how the climate of the UK is a result of its position on the Earth (8 marks).

9. Analyse the factors that cause differences in the hazards posed by volcanoes around the world. (40 marks)