Silence please be quieter
This project idea was contributed by Peter S. Fox
|Exam Board||Components that this project links with|
|AQA A||Unit 2, Section A: Changing Urban Environments|
|AQA B||Unit 1, Section B: The Urban Environment|
|Edexcel A||Unit 1, Section A: Geographical Skills
Unit 3, Section A: Settlement Change
Possible investigation for controlled assessment
|Edexcel B||Unit 2, Section A: Living Spaces
Unit 2, Section B: Changing Cities
|OCR A||Unit A673: Similarities and Differences- ‘your place’|
|OCR B||Theme 2: Population and Settlement|
|WJEC B||Theme 1: Challenges of Living in a Built Environment|
This article sets out to illustrate how noise pollution can be an interesting topic of study both in a practical sense, by the undertaking of a noise survey on a local scale, but also how noise maps can be an important new way of thinking and assessing the environment and of understanding the geography behind it. Many of the noise maps discussed here provide simple but effective ways of using GIS and a number of other ICT skills. Since noise is probably quite a new area for study the article explains in some detail what noise is and how it can be measured. It also gives examples of how noise maps might be used to facilitate learning and teaching.
The impact of noise on our health and the quality of our lives has probably been ignored for a long time. It has been estimated that about 20% of the population of the European Union suffers from noise levels that are unacceptable and that a larger proportion live in ‘grey’ areas where levels are such that they can cause annoyance during the day and night.
The EU issued a green paper on the future of Noise Policy in 1996 for consultation and the policy has now been agreed and approved. Noise maps have to be produced for all built up areas with over 250,000 inhabitants and along the routes of roads, railways and for major airports to fulfil this EU directive.
Noise mapping is a method of collecting and displaying information about noise and Defra published the first noise map in May 2008. The Greater London Authority Act 1999 required the Authority to produce a State of the Environment Report on ambient noise strategy.
A noise map of some areas of Britain especially Scotland and Northern Ireland and parts of Bristol together with the noise ‘footprints’ or ‘umbrellas’ of all the major British airports were available before this date and provide a rich source of information for analysis. These together with a noise map of Greater Paris are available online for free. A considerable amount of work undertaken by a number of local authorities is available on their websites, such as Liverpool and some of the London Boroughs.
What is Noise?
Ambient Noise: Ambient noise is noise from fixed industrial sources, such as noise related to transport, including road, rail, aircraft and water traffic together with any noise caused by vibration.
Point Source Noise: This noise is generated at a point, such as a firework display or pneumatic drill and is not normally plotted on a noise map because it tends to be transient.
A noise map plots place and noise levels using coloured or black contour / isohyet lines on an area. They show the ‘hot spots’ where it is noisy and ‘cooler’ areas where it is quiet. Noise maps can be produced in many ways but they are normally generated by computer software which predicts noise and the noise level at a specific time of the day or night. The computer software takes into account the spread of noise, traffic, buildings and the nature of the surface – whether it absorbs noise, such as farm land, or reflects noise, such as concrete or water. An example of how a noise map can be interpreted appears on the example that you can download below.
Making a Noise Map
Noise maps can be made of ‘micro’ areas, such as the inside of school buildings or school grounds (rather like microclimate maps) or larger local areas based around the local OS map. Noise levels can be recorded by undertaking fieldwork or simply by using the students own knowledge of their local environment.
A noise measurement scale, based on the Paris noise map classification, although imprecise, provides a helpful tool. A suggested key is set out in Table One(?). Students can work out their own scale based on noise levels with which they are familiar, such as loud disco to the examination room where silence is required. It is helpful to have about five divisions on the scale.
Noise maps, rather like traffic flow maps, are dynamic; noise levels vary all the time, and are based on average readings, ‘flattening’ out the highs and the lows for a specific time period. It is important that the students work out that some places, like their school, are particularly noisy in certain places and at certain times of the day. For example, the school grounds may only be noisy before school, during breaks and lunchtimes and even this pattern may be changed during a ‘wet break’, the school holidays or at the weekends. But some areas and features have a constant ‘hum’ of noise especially on main roads and the local park may be nosier that pupils think it might be when a noisy football match is being played.
Noise measurement collection points do need to be quite ‘dense’ in that noise levels can change quite quickly if the noise is masked or absorbed so as well as recording the level of the noise it is also important to record the type of environment it is measured in and the current weather which introduces another variable. A table has been drafted to enable students to do this, see Table Two(?). A map of perceived noise levels may be completed before the actual noise survey is done; this may provide a helpful source for comparison and discussion.
Online Noise Maps
There are numerous Noise Maps to be accessed online. These can be examined before or after any fieldwork or as a standalone. The maps can be printed out or used on screen. They are forms of Geographical Information System where information is stored for a specific location and for a specific time and can be interrogated and displayed in different ways. Suggestions for use: The maps could be used to choose the best place to live or, if you are a visitor, to have a quiet picnic in the summer. It could be used to predict where the greatest density of traffic will be – reflected by the greatest noise values in the day and at night. A new location for a housing area might be selected and examined in terms of the surrounding noise levels. Here are a selection of noise maps available to view online.
Noise Mapping England
The England noise maps were launched by Defra (Department for Environment, Food and Rural Affairs) in May 2008. Some of the maps were compiled well before that date. There are a variety of different maps available from detailed maps of the major cities of England, searchable by post code and showing day and night noise levels from roads, industry, railways and airports with a statistical chart for each given map. The maps are quite small and not as high a resolution as the older, decommissioned London map or indeed the maps available of Scotland, but they can be enlarged for use on PowerPoint or another presentation package. There are also a number of PDF maps of areas of England showing major railway and road routes with their associated noise levels.
The Scotland Noise Map
This is an interactive GIS map of the central lowlands of Scotland covering the area between Edinburgh, the east coast and Glasgow on the west. The map can be magnified and has a search facility. The major sources of noise pollution can be identified and different sources can be switched on and off.
NOISE Northern Ireland
This map covers the whole of Northern Ireland. The map can be magnified and is searchable although the resolution is not as good as the Scotland map when viewing specific small areas.
This is an interactive GIS map for part of Bristol. Features of the map can be switched on and off to enable the map to be viewed in different ways. The map can be magnified and major sources of noise pollution identified. The map can be toggled with the Google Earth map of the same area, labels added or removed, places identified.
The London Noise Map
This was probably one of the best maps to use but it has been decommissioned. But see link above for more information about this map.
The Airport Noise Maps
These are available online for all of the major airports in Britain. Two maps are available, one for the day and one for night times. The maps have an OS map base and show dB noise levels as ‘isohyets’ to make a distinct sound footprint or umbrella. Don’t forget sound moves in three dimensions. Suggestions for use: It is possible to work out for each airport which urban areas and villages are affected by the noise footprint. The maps used in association with images from Google or Flash Earth can illustrate those most affected and students can work out strategies to minimize the effect on these areas, such as noise management in terms of building design, changing the flight paths and time frames for flights or many other alternatives. The impact of extending the airport and its impact on the noise footprint can also be extrapolated from the pattern.
Noise can be managed in many different ways. A potential lesson idea is the opportunity for students to work out the best method of management for a given location together with its advantages and disadvantages.
Students could brainstorm the different ways that noise can be reduced. These might include the modification and reduction of the noise at source- for example quieter cars, pedestrianised zones, zoning of people away from traffic, new transport systems such as trams and bus lanes. Alternatively, there might be methods of deadening or baffling noise with the use of different materials for example ‘quiet’ road surfaces which absorb noise and vibration or the use of fences to deflect noise from vulnerable areas such as housing estates as illustrated in figures one and two. Management techniques can then be rated according to the number of people benefited and the cost of implementing the schemes.
Suggestions: An area, road, airport or school could be selected and maps or pictures annotated to suggest the possible ways of minimising the impact of noise. See example in the download below.