Extreme weather in the UK

What is the difference between weather & climate?

Weather is the day-to-day conditions of the atmosphere whereas climate is the average weather conditions calculated over a 30 year period

What factors affect the UK’s weather?

Prevailing winds

Air masses

North Atlantic Drift

Continentality

What is prevailing wind?

The dominant direction of wind

What direction does the UK’s prevailing wind come from?

The south-west

The direction of the UK’s prevailing wind explains why…

The UK experiences moderate temperatures & high rainfall

This is because it comes from the south-west, meaning that it travels over the Atlantic Ocean which is relatively warm

What is air mass?

A large body of air that transfers conditions of heat & moisture from its source as it travels

What are the different air masses affecting the UK?

What is the source & characteristics of the Arctic Maritime air mass?

Source: The Arctic

Characteristics: Cold & wet air that brings snow in the winter

What is the source & characteristics of the Polar Continental air mass?

Source: Central Europe

Characteristics: Cold & dry air in the winter that brings sharp frosts, hot & dry air in the summer that brings sunny weather

What is the source & characteristics of the Tropical Continental air mass?

Source: North Africa

Characteristics: Hot & dry air that brings hot summers

What is the source & characteristics of the Tropical Maritime air mass?

Source: The Atlantic

Characteristics: Warm & moist air that brings cloud, rain & mild weather

What is the source & characteristics of the Polar Maritime air mass?

Source: The Arctic Sea & Greenland

Characteristics: Cold & moist air that brings cold & showery weather

What is the North Atlantic Drift?

A powerful ocean current that originates in the Caribbean & is responsible for maintaining warm conditions on the western side of the UK

The North Atlantic Drift explains why the western side of the UK…

Tends not to experience as severe winter weather conditions compared to the rest of the UK

What is continentality?

Distance from the sea

Continental areas warm up & cool down very ____, whereas ____ areas warm up & cool down ____

1 = Quickly

2 = Maritime

3 = Slowly

Continentality explains why the eastern side of the UK experiences…

Hot summers & cold winters as well as relatively low rainfall

What extreme weather have air masses caused in the UK?

Tropical Maritime → Winter storms

Arctic Maritime → Heavy snow

In ____, the UK was battered by a succession of winter storms from the ____, driven onshore by strong ____ winds.

This was the stormiest period of weather experienced by the UK for ____ years.

1 = February 2014

2 = Atlantic

3 = Western

4 = 20

What impacts did the February 2014 winter storms have on the UK?

- Widespread transport destruction due to extremely dangerous conditions on exposed coastlines

- The SW mainline railway was severely damaged, cutting off a transport link to the SW for many weeks

- Coastal flood defenses were destroyed by huge waves, causing floods in Cornwall, Devon & Dorset

- Many trees collapsed, resulting in around 100,000 homes & businesses to be without power. This also caused roof damage & 1 member of the public even died

From ____ to ____, the Arctic Maritime brought very low temperatures & heavy ____ to the UK.

It was the most severe period of winter weather since ____.

1 = December 2009

2 = January 2010

3 = Snowfall

4 = 1981 / 1982

What impacts did the 2009-2010 heavy snowfall have on the UK?

- Night-time temperatures often fell below -10°C in Scotland

- In England & Wales the snow was up to 20cm deep & it was 30cm in Scotland

- Roads were blocked, trains were cancelled & airports were disrupted

- The electricity supply to over 25,000 homes was disrupted due to ice bringing down power lines

- Several people died due to accidents caused by the snow & ice

- Farm animals across the UK were severely impacted, especially sheep in mountainous areas