CASE STUDY: Britain's Weather and Climate
Britain has a variable climate. The weather changes from day to day.
Being an island, Britain is affected by five air masses at different times.
An air mass forms when air remains stationary over a place for several days. Different air masses bring their own characteristics and types of weather to the UK. Figure 3 (left) shows the main air masses affecting the UK.
Descriptions of air masses affecting the UK and factors influencing its weather are listed below.
The Met Office information video below explains the different air masses and the types of weather they bring with them.
Main air masses affecting the UK (above)
The Air Masses Affecting the UK
The Polar Maritime Air Mass: occurs frequently over the UK and tends to bring cool and wet weather with it. It brings air from the north-west. It brings heavy showers and strong winds. The Polar Continental Air Mass: brings cool dry weather from the north-east but this air mass does not affect the UK frequently. The Arctic Maritime Air Mass: Brings wet, cold air from the Arctic and is responsible for bringing snow to the UK in winter. The Tropical Continental Air Mass: Is the least frequent brings with it warm, dry conditions. It only occurs in Summer and can bring heat wave and drought conditions. The Tropical Maritime Air Mass: Brings air from the south-west (Atlantic Ocean) and is the most common air mass over the UK. It brings warm weather in the summer and mild weather in the winter. It can bring with it long periods of rain. See below for maps and satellite images of air masses over the UK. |
Factors Affecting UK Temperature
Altitude: Temperature decreases by approximately 1°C every 100m increase in height. In the UK, this can be seen in the Scottish Highlands where altitudes can be above 1000m. This means that temperatures here can be about 10°C colder than other, more coastal areas. This allows snow to settle for long periods of time in the highlands. Prevailing Winds: The prevailing winds of the UK are from the south-west, from the Atlantic Ocean. Prevailing winds travelling over warm surfaces bring with them warm weather and so the prevailing winds bring with them cool temperatures in summer, but milder weather in winter. Distance from the Sea: As the UK is an Island and surrounded by sea, it gets cool in the summer and mild in the winter. The largest water heat store for the UK is the Atlantic Ocean. This is why western parts of the UK are warmer than eastern parts in the winter. Ocean Currents: Britain has a Maritime Climate and therefore coastal areas are affected by ocean currents. The west coast of Britain is kept warmer in winter than other places of a similar latitude because of the impact of the North Atlantic Drift. This current of warm water originates in the Gulf of Mexico. |