Introduction The storm of 1987 occurred on the 15




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Introduction
The storm of 1987 occurred on the 15th and 16th of October due to a depression that grew quickly in the Bay of Biscay and travelled quickly North resulting in large amounts of disruption in the UK. This depression grew due to a combination of factors including the unusual position of the jet stream and lead to particularly strong winds, up to 100knots in the UK. This went on to cause damage and destruction, with a total of 19 deaths in the UK, and many buildings being damaged.




Bay of Biscay- this is where the depression was formed

The UK was badly affected by the storm, particularly the south and south east of the country


Executive Summary
Depressions are the cause of storms. They affect the UK and help give it the variety of weather. The depressions are formed by a cold front meeting a warm front, causing the cold air to undercut the warm, which rises. The different stages of the depressions cause different weather conditions. The warm front can produce nice warm weather, but when the cold front come in there it can be cold and there is a high chance of rain.

The Great Storm of 1987 is a rare occurrence – major storm events like this only happen around once every 200 years. The depression formed in the Bay of Biscay which moved across the UK causing great destruction. Some of the causes to why it had such a major impact include the fact that it was poorly forecast, unusually strong and that it occurred in the early winter windstorm season.

Many different areas where affected by storm. In total 19 lives were lost; 150,000 houses were lost; and 3000 schools were closed. There was one main environmental factor which was the loss of trees – at Toys Hill in Kent 97% of the trees were lost. The entire cost of the storm was amounted to £1.2 billion. As the cost was so great the insurance companies raised its premiums, affecting many people. Many industries were affected by the storm: the stock market came to a halt; the price of hardwoods dropped; and factories and offices were closed. The storm greatly affected the public transport of the country, with roads blocked; train lines blocked and flights cancelled.

Today the situation in the UK would be very different than in 1987. Meteorological technology has improvedsince1987. Today we can predict the weather and storm event, so we can therefore prepare. The emergency services were very important in the response to the storm. Since the storm they will have had more training to deal with future incidences. People can prepare today by listening to the MET office weather warnings, cutting trees branches and using defences, such as sandbags.



Storm Events

Miserable, wet and stormy weather is associated with the movement of depressions.




Depressions – an area of low pressure in temperate latitudes usually associated with cloud, rain and strong winds.

Most of Britain’s weather comes from the passage of depressions. They normally travel from west to east; bringing changeable weather with rainfall as both warm and cold fronts pass over. These occur frequently due to the Polar Front Jet Stream and meeting point of different air masses.

This shows the movement of the warm and cold front with the weather produced. The warm (red) area is lighter tropical air rising over cold air. The cold (blue) areas have heavier polar air that sinks below the warm air.

Depression moves from west to east.


Stages of Depressions

There are four stages of a depression:



  • Early/Origin stage

  • Open/Maturity stage

  • Occluded stage

  • Dissolved stage.



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Characteristics of Depressions

A marked comma-shaped cloud pattern that is typical of a mature depression. This depression can be up to 1700km in diameter and can last for between four and seven days. There are different types of cloud associated with different parts of the mature depression.

Precipitation occurs in three parts of a depression: at the warm front where the warm air rises over the cold air; at the cold front where the cold air undercuts the warm air; at the centre of the depression where air rises to compensate for inward-moving air. Cloud develops at the compensation level. Rainfall will result if there is sufficient condensation and hygroscopic particles. The release of latent heat helps to drive the depression by encouraging uplift of air and intensifying lower pressure near the ground.
Modern Models of Depressions

Conveyor belt model

This is the most widely accepted model of a depression based on the work by Browning et al. (1973). At the 500mb level is the cold dry air of the upper troposphere. This divides to pass above the depression and form the mass of cold air behind the cold front. A flow of cold air approaches the centre of the depression which initially passes parallel to the warm front and, as it leaves, rises in a clockwise direction of the system at a higher altitude. A belt of warm air, originating in the south, approaches the cold air at the warm front, it is forced to rise in a clockwise direction. This warm air then flows away from the depression.


Ana front

Occurs when the warm air is generally rising in a flow that is not quite parallel to the cold front. This encourages instability and heavy rainfall.


Kata front

Where the air flows away from the cold and warm fronts and is not forced to rise. The broadly descending air leads to more stable conditions and less intense rainfall.


Causes of the 1987 Storm- Formation and Forecasting
In the afternoon of the 15th of October 1987 in the Bay of Biscay, north of France, a depression was developing. The depression started to form due to a slight disturbance along a cold front, and went onto form a storm which typically occurs once in 200 years.
A
Diagram 1
t midday, with a centre at 46oN, 90W, in the bay of Biscay, the pressure reached 970mb, this continued to fall and by 6pm it reached 964mb, by 630 the first gale warnings were released for coasted areas along the English Channel. The rapid dropping in pressure was caused by warm air from the tropics linked with Hurricane Floyd which with the cold air moving south from Iceland caused a large pressure gradient force.

The formation of the depression was contributed to by the jet stream which was further south than normal just north of France instead of just north of Scotland. Therefore the depression which would normally have gone north of the UK hit the UK. Shortly after midnight on the 16th of October the depression reached the UK and moved north east across the country, with wind up to 81mph in the south east and at force 10. At 1.35 a.m. on 16 October, warnings of Force 11 were issued and by 5.30 am it reached the Humber estuary when the pressure was about 959 mb, (diagram 1). There was also a large charge in temperature, in areas south of a line from Dorset to sussex, there was 60C per hour (diagram 2). Gusts of 70 knots in the south east of England, but the highest measured wind speed in the UK was a gust of 100 knots at Shoreham on the Sussex at 3.10am.




Forecasting is considered poor for the 1987 storm as it had a particularly unpredictable nature and the area wasn’t being well monitored due to cost cutting at the time. In the evening there was little information given out by the media suggesting there will be heavy wind, only heavy rain, however a server weather warning had been given to emergency authorities such as the Fire brigade.



Effects





Short Term

Long Term

Social

  • 19 lives lost, however this figure was very low considering the severity of the storm

  • 150,000 houses were without telephone communications

  • In Suffolk all 360 schools were closed and a total of 3000 schools were closed in the South East area

  • People were terrified

Environmental

  • 15 million trees were blown down as a result of the storm such high numbers were due to the fact most deciduous trees had not lost there leaves when the storm hit and the antecedent conditions meant that the ground was soft.

  • Toys hill in Kent lost 97% of trees in the storm

  • High numbers of fallen trees create deadwood, these become habitats for many insecticides including woodlice and centipedes, this then has a direct effect in the food chain benefiting the bird population

Economic

  • 6000 calls to the fire brigade in 24 hours

  • Holt in the stock market

  • Temperate drop in the price of hardwoods.

  • Factories and offices were closed as people couldn’t get to work

Built

  • 5 million homes were without electricity

  • Falling trees blocked roads and railways and destroyed homes and cars

  • Dover port was closed for the first time in the 20th century and channel cross ferry was beached at Felixstowe

  • Underground brought to a halt

  • London experienced the first blackout since the blitz

  • Flights cancelled at Gatwick and Heathrow

  • Clean up operation needed to improve built environment and for repairs.


Aftermath

After the storm event, which lasted for one evening, 15th October 1987 – 16th October 1987, many homes, buildings and transport links were damaged. The storm took 18 lives, and cost £1 billion worth of damage. Overall, the storm was not well forecasted, which made the extent of the damage, and cost of the damage to be larger, due to the lack of response, reflected by the MET Office.


Solutions

The storm caused damage throughout the UK, causing solutions and responses to be drafted in to help resolve the damage the storm had caused.

The MET office was highly criticised by much of the media and by journalists, claiming it did not cover or forecast the storm correctly. Yet the UK being an MEDC, due to its high economic wealth, should have been able to react more rapidly to the storm, and the damage it had caused. The MET office was the main institution to receive the blame for the lack of information, support and coverage of the storm, and its ineffective response.
H
Infrared satellite image showing the storm at 0230 UTC 16 Oct 1987
owever, if the storm event occurred again in 2009, the UK would be better prepared for it, due to many factors. Meteorological technology which was ineffective in 1987 at predicting the storm, is now, over 20 years later, much more efficient, and is known to be very accurate when predicting events such as heat waves, flooding, and depressions such as storms.

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Destruction by Great Storm 1987


lso, with media technology growing vastly and the internet and television becoming the public’s main source of news, programmes such as the BBC have become “interactive,” similarly to Sky. This has meant they are able to see weather forecasts for a week ahead, and predict temperatures and conditions early, and accurately. Due to this, there are constant and high media coverage of weather events and conditions, with the MET Office giving warning of heat waves, flooding, thunderstorms etc. This has meant that the public has become better prepared for the occurrence of these kinds of events, and has made them more frequent in the public eye. This has mainly provided a better understanding and more awareness for the public. Over the last 20 years, the people have become better educated in emergencies, on how to deal with freak weather incidents, and how to respond in an efficient and effective way.

Responses

Police and emergency services were under immense pressure to respond to the destruction the door did. Rescue workers faced an unprecedented number of call-outs as winds hit 94 mph London and over 110 mph in the Channel Islands.

The response from the media in relation to the storms was highly critical over the BBC weather man, Michael Fish. Fish had previously, the day before, stated that a woman had called into the BBC concerned there was a hurricane on its way. However, he immediately disregarded this, and claimed there was no hurricane or storm forecast for the coming day. The storm brought much criticism about Fish’s accurate weather readings, with the media slamming the BBC and the MET office for insufficient information regarding the location of the storm and the underlying damage it would do.

The London Fire Brigade dealt with 6000 calls in 24 hours, in concern to trees, homes, and buildings having been destroyed. Telecommunications were blown down and unavailable for a period of time during the amount of help and emergency calls available to the public.

The storm cost a total of 18 lives and hundreds of people were injured. The storm cost an estimated £1 billion in repairs damages and clear-up costs. The writer Oliver Rackham and the charity Common Ground were the most active in trying to prevent unnecessary destruction of trees which, although fallen, were still living, which ad been damaged by the prevailing winds from the storm.

The insurance industry had to brace itself for huge payouts on mainly household’s policies covering the storm damage. Len Turner of Ealing Council said: "It's going to take an enormous amount of effort and money; I hope we can look to the Government to support us because the burden on local rate payers is going to be enormous.” The storm was the first insurance catastrophe of the modern era.



DIY sales increased dramatically, reported chain stores, as an unpredicted demand for tools and materials were bought to help restore households and buildings which had been damaged by the storm.

Ways to Prevent the storm causing extensive damage:-

  • To prevent flooding, using defences such as sandbags, help absorb water quickly, due to sand having more pore space to absorb the water.

  • Cutting and pruning of branches on trees reduces the likelihood of when there are prevailing winds and strong storms, debris and trees are less likely to destroy and damage buildings, transport and housing.

  • The MET office’s warning prior to a storm, heat wave, thunderstorm etc. makes people more aware and understand the issues of a storm, and how to act in the case of an event, such as the Great Storm of 1987

This map shoes the number of deaths from storms




Conclusion

There is no doubt that the storm in 1987 was a phenomenal weather event that produced many impacts, most of which were negative. The storm was unexpected and not forecasted and this increased the impacts of the storm of which were social, environmental, economic and built. Damage to infrastructure, loss of life and productivity are just some examples of the impacts from this weather event. In response to storm over 1 billion pounds were needed in the clear up operations and measures have been put into place along with advances in technology to improve forecasting and warning systems, these will hopefully reduce the impacts of any future similar storm events. The storm which occurred in 1987 is a 1 in 200 year storm, however the effects of climate change may mean events like this may become more common.


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