1. UK Storms
Aims:
To complete a detailed case study on The Great Storm in the UK in 1987.

2. Storms that Hit the UK are Temperate Storms
Temperate storms occur in temperate climates – these are climates that are found at mid-latitudes, 30-60° north or south of the Equator.
They range form mild (e.g. rain showers and km/h winds) to severe (e.g. thunderstorms and 120 km/h winds). They can bring strong winds, rain, hail, sleet or snow.
They generally cause less damage than tropical storms. Typical impacts include road closures, power cuts and damage to trees. Occasionally temperate storms can be very severe, with winds strong enough to damage buildings.
Temperate storms are caused by depressions:
Depressions often form over the sea in autumn when the water is warm – warm surface water leads to warm, moist air which rises. When this warm air meets the polar front it rises rapidly above the cold polar air creating an area of low pressure, along with condensation and heavy rain.
A steep pressure gradient between the two air masses drives strong winds, which spiral around the depression.
Steep temperature gradients in a depression affect the storm’s strength – a strong temperature gradient means there is also a stronger pressure gradient (warm air has lower atmospheric pressure than cold air) which drives strong winds.

3. The Great Storm Hit the UK in 1987
On the night of the 15th October 1987 the UK and France were hit by a severe temperate storm…
On the 15th October, pressure in the centre of the depression fell from 970 mb at midday to 953 mb at midnight (much lower than the average air pressure in the UK – 1013 mb).
The storm hit the south coast of Cornwall and Devon shortly after midnight, moved across the Midlands, and reached the Humber Estuary on the east coast at around 5.30 am on the 16th October.
The South East suffered especially severe winds between 3 and 6 am, with gusts up to 196 km/h at Gorleston in Norfolk. The highest hourly mean wind speed was recorded at Shoreham-by-Sea, where winds of 136 km/h blew for 20 minutes continuously.
After 6 am the depression began to weaken and moved over the North Sea.
The Storm was Caused by a Depression with Rapidly Falling Air Pressure
The depression began over the Bay of Biscay (north of Spain and west of France) as south westerly winds carrying warm, wet air from the North Atlantic met north easterly winds carrying cold air from the Pole.
The depression deepened rapidly due to unusually warm sea surface temperatures in the Bay of Biscay and a steep temperature gradient between the two air masses. Low atmospheric pressure in the core of the depression led to the development of very strong winds.
The polar front jet stream was located further south than normal, so the depression formed over northern France and southern England, rather than to the north of Scotland.

4. Impacts included Deaths, Infrastructure Damage and Economic Costs
SOCIAL IMPACTS
18 people died in England, and another 4 in France.
Power and telephone lines were knocked down (mostly by falling trees) homes lost their telephone connection, and several hundred thousand people had no electricity for more than 24 hours.
Some historical buildings were damaged or destroyed, e.g. Shanklin pier on the Isle of Wight was destroyed by waves.
ECONOMIC IMPACTS
Over 1 million buildings were damaged. Insurance claims totalled £1.4 billion.
Transport was disrupted as fallen trees blocked roads and railways.
Gatwick airport closed because it had lost power.
Thousands of boats were wrecked. MV Hengist, a cross channel ferry, was beached.
ENVIRONMENTAL IMPACTS
About 15 million trees were blown down.
Some areas lost 97% of their trees, causing a loss of woodland habitat.

5. Responses included Clean Up Operations and Improved Forecasting
During the storm emergency authorities (e.g. fire, police, ambulance, and coastguard) dealt with huge numbers of emergency calls – four months’ worth of calls in one night.
After the storm a massive recovery and clean up operation began:
Phone companies and electricity boards worked round the clock repairing and replacing equipment until phone lines and power were restored.
Highways agencies began clearing roads, and railway companies cleared railways.
Forestry workers began collecting the fallen trees in forests (around 4 million m3 of timber needed recovering). It took hundreds of workers over two years to collect and store all the timber.
The Forestry Commission established the Forest Windblow Action Committee to help woodland owners recover fallen trees and offer advice on replanting.
The Met Office were criticised for how they forecast the storm and issued warnings:
Severe storm warnings were only issued about three hours before the storm hit.
The Ministry of Defence were only warned that military assistance might be needed to help deal with the impacts of the storm at around 1 am on 16th October.
There was an inquiry, and changes were made:
More observations of weather systems are now made by ships, aircraft and satellites.
Improved computer models are now used to forecast weather.
The government established a national severe weather warning service to improve the way severe weather warnings are made and issued.

6. Exam Question
Describe the impacts of, and responses to, one temperate storm that you have studied.
(10 marks)