UK Weather Hazards (AQA GCSE Geography)

Weather Hazards of the UK

UK's climate

• The UK has a mild, seasonal climate-cool, wet winters and warm, wet summers

• Continentality, the North Atlantic Drift and air masses affect the UK weather

  • Continentality:

    • Coastal areas are warmer in winter and cooler in summer 

    • Seas take up the heat in the summer, cooling the surrounding land

    • During the winter, the heat is released, keeping the coastal land warmer

  • North Atlantic Drift:

    • Ocean currents bringing warm waters from the Caribbean to the west coast of the UK

    • This keeps the west coast of the UK warmer than other regions of the UK

  • Air Masses:

    • Large volumes of air with similar water content and temperatures

    • Classified by the region where they form: 

      • Arctic or Polar cold air

      • Tropical warm air

      • Maritime wet air

      • Continental dry air

• Five types of air masses that bring different weather to the UK:

The UK's Air Masses

UK's extreme weather

• Depressions:

  • Bring very wet and windy with unstable, low-pressure weather

  • Depressions form when warm air meets cold air

  • Form over the Atlantic Ocean, then move east over the UK

  • The strongest winds and heaviest rains are in the autumn due to sea waters releasing summer heat and meeting colder Polar air

• Anticyclones:

  • Bring very cold or very hot, stable, high-pressure dry weather

  • Also, form over the Atlantic Ocean and move east over the UK

  • Winter anticyclones bring long periods of cold, foggy weather

  • Summer anticyclones cause periods of hot, dry, clear weather

UK weather hazards

• The UK experiences different weather hazards: rain, wind, heatwaves, thunderstorms, hailstorms, drought, snow and ice

Types of Weather Hazards in the UK

Changes in UK Weather

• The UK's weather is becoming more extreme

• The Intergovernmental Panel on Climate Change (IPCC) has warned that temperatures will increase during this century

• Global warming increases the frequency and intensity of extreme weather events through increased evaporation and rainfall

• Scientists believe the UK will continue to experience higher amounts of rainfall and increased temperatures

  • Since the 1980s, extreme winter rainfall has increased

  • UK temperatures have increased by about 1°C since 1980

• Other examples of extreme weather in the UK include:

  • More frequent and heavier rainstorms, particularly in the autumn 

  • Gales

  • Flooding

  • Heatwaves

  • Droughts

  • Thick fog

  • Heavy snowfall

• Temperatures have become more extreme in recent years

  • Unusually cold winters occurred in 2010-11 and 2014-15

  • Temperatures fell to -10°C with frost destroying crops and killing livestock

  • Over 17,000 trains were cancelled in 2014 due to the freezing conditions and flights were delayed

• Major flooding follows frequent, heavy rainfall in the autumn

  • The UK is regularly hit by depressions, which bring heavy rain to the west coast of the UK

  • During the winter of 2013/14, there were prolonged Atlantic storms, with persistent rainfall and gale-force winds

  • Causing the Somerset Levels to experience unprecedented flooding 

  • Roughly 10% of the area was underwater at the height of the flood

  • Over 600 homes and 6880 ha of agricultural land were flooded, along with a number of villages being cut off through flooded roads 

Case Study: Extreme Weather in the UK

Beast from the East 2018 

• Background:

  • It began in January 2018 when the stratosphere suddenly warmed

  • This generated a large rise in air temperature of around 50 °C in an area approximately 29 km above the Earth at the North Pole

  • This sudden warming weakened the jet stream (which usually brings in the warmer air) and allowed the cold air from western Russia to 'flood' over Europe 

• Social impacts:

  • Schools across the country were closed for up to 3 days

  • 10 killed across the country

  • Hundreds trapped in their cars on roads and motorways

  • The UK issued a gas deficit warning

  • Gas supplies were running low and thousands were without power

  • NHS cancelled non-urgent operations

• Economic impacts:

  • The cost to the UK economy was estimated at least £1bn a day 

  • Shops, leisure facilities, theatres, cinemas and restaurants were severely impacted as people were told to stay indoors and not travel

  • Trains were stranded on tracks overnight, causing delays for many businesses

  • Thousands of businesses without or reduced power, causing loss of earnings

  • Road closures meant workers and materials couldn't get through, forcing some businesses to close whilst still accumulating costs

• Environmental impacts:

  • Farmers lost crops and livestock during the freezing conditions

  • 15-20 cm of snow fell over 3 days

  • Snow drifts of up to 7 m in some rural areas of the UK

  • Temperatures dropped to -10°C with a wind chill of -22°C in some places

  • Wind speeds exceeded 70mph

• Management strategies included:

  • The Met Office issued a red warning to prevent people from travelling

  • The government asked businesses to reduce their gas usage so the country didn’t run out, allowing people to have their heating on for longer

  • Community centres were opened for those who are homeless to avoid further deaths from exposure to the extreme temperatures

  • Snow ploughs gritters and tractors out to clear roads to help people travel again

  • Armed forces deployed to rescue drivers and drive NHS workers to work to help the sick and poorly

  • Gregg's delivery van driver handed out food to those trapped in their cars to avoid hunger

  • Taxi firms provided help to the elderly by bringing shopping and medicines to those in need

  • Red Cross issued blankets to people stranded in Glasgow Airport