1. (which stands for Geographic Information Systems)
Lesson 2 All about GIS
(which stands for Geographic Information Systems)

2. What is GIS?
Introduction: Paper maps only tell us where a place is. GIS uses digital maps and information to help us make decisions and solve problems
Hardware: GIS runs on mainframe computers, PCs, small PDAs or even mobile phones to organise information and map the results of investigations.

3. Software
GIS software is a set of computer ‘tools’ for collecting, storing, processing and displaying sets of information linked to places on maps.
There are different types of GIS ‘tools’: for instance, a GIS that analyses land use is different from a GIS that maps the quickest route to a fire.

4. Maps
Electronic maps and images: An essential component of any GIS is some kind of map or image of an area. This can be a digital map, satellite image or aerial photograph.
Many GIS will use a full range of map data and images as a base to link information against.
The maps are produced either as raster or vector data
Raster maps
These are images made by a series of coloured dots on a screen (pixels), just like high quality digital photographs, e.g aerial views are one source
Raster maps can be thought of as ‘unintelligent’ as you can only obtain information that is visually represented on them.
Raster maps take up a lot of computer storage space but can be very useful as background maps to other information.

5. Maps
Vector maps Each vector map feature is recorded using XY coordinates.
These may be a single point (like a trig point), lines (such as roads) or polygons (such as buildings or woods).
The referenced features of vector maps make it possible for a GIS to link information from spreadsheets and databases to the maps.
Vector data is stored in themed layers such as
Roads, water, settlement

6. Maps
Data:It is easier to make sense of complicated spreadsheets and databases when they are linked to maps in a GIS.
It is estimated that over 80% of all data has some link to a geographic place.
People:The vital ingredient! We need people who understand digital maps and databases and know how to use GIS to organise the data on maps.
They can ask the right questions and produce new maps showing the results.
This helps to plan the way we live and use our environment for the future.

7. An example of how it works
The Hole Story

8. The Hole Story
The vast networks of underground pipes supplying our water, electricity and gas are hidden from view, so how do we know where it’s safe to dig?
Louise works for a water authority to maintain the company's network of water mains and sewers.
She uses a GIS to create a complete overview of the pipeline which helps her to monitor its condition and performance.

9. The Hole Story
To minimise the risks involved in digging trenches, laying cables and other maintenance and building projects, utility companies must share their underground asset maps upon request with other organisations.
A GIS is built up of lots of different layers of information which users can Switch on and off depending on their needs.

10. The Hole Story
Information can be shared between utilities via a secure website.
The website uses a GIS to pinpoint the location of water mains, gas pipes, electricity cables and sewers as well as details of current and future work
Allowing all the utilities to access this information means that all utilities can agree to carry out work at the same time.
Digging up the road only once helps to minimise public disruption and saving time and money.

11. One more example
It’s a breeze

12. It’s a breeze
Wind farms can provide a source of alternative energy but finding the right location for the turbines can be difficult.
Dave works for an energy company that is keen to investigate the use of wind turbines as an alternative way of generating power.
He is asked to work on a project to identify suitable sites for a new wind farm.
The location needs to balance environmental concerns with operational efficiency..

13. It’s a breeze
Dave has followed the debate in the newspapers and knows that the effect of the turbines’ appearance on the landscape is a major concern.
Many other factors, however, also need to be considered when choosing a site.
These include wind speed, wind direction, distance from the existing electrical grid system, access to the site, size of the site and the shape and profile of the land.

14. Anyone spy anything wrong with this map?
It’s a breeze
By inputting data from various sources regarding weather, civil and military airfields, telecommunications and environmental organisations, Dave begins to put together a case for the available site.
He still needs to take into account the height and spacing of the turbines so that they can produce the required amount of electricity balanced against their visual impact
Anyone spy anything wrong with this map?

15. It’s a breeze
Dave adds height data and information to produce a 3D model giving a virtual view of the site as it would appear from different directions, distances and perspectives.
This enables him to focus on particular locations to check the turbines’ impact on the view.
The information Dave produces is used to support planning applications and to reassure local residents that the wind farm will cause minimal disruption.

16. To find out if you could use a wind turbine on your house
ASK YOUR PARENTS FIRST
Then go to
Enter business type – residential, your name etc and press Lookup
If the answer is 5 or better still 5.5 m/s then your home is potentially a good place to put a small wind turbine!

17. Now for the worksheet and to work towards your homework
and

22. Click on the ‘i’ by Lockerford to find …
Population - 2,000
A small village to the west of Melchester.
It grew on the site of a ford that farmers used when bringing their cattle to Melchester market.
Now seen as one of the most desirable and expensive places to live in the area.
Lots of commuters choose to live there.
Latest flood information:
Casualties – 0
Evacuations people
Estimated insurance claims - £ 50,000

23. 1. Locker Valley Storage basins
Total Cost = £ 5.0 million
Earth-moving equipment will dig out two large basins connected to the river by drainage channels.
At times of high water, flood gates are opened allowing water to drain away from the river into the basins
The Locker Valley meadows are home to many wetland bird species that will be disturbed during construction. However, long term the wildlife will benefit.
The people of Lockerby are likely to be upset by all the noise from the earth moving machinery.

24. Having gathered the information
You will need to put in a score
But you cannot really do that until you know about ALL the sites
Hence the worksheet I hope you have open!

25. 2. Locker Brook Relief Channel
Total Cost = £ 10.0 million
A large drainage channel connecting the Locker Brook to the River Falmer.
At times of high water, a flood gate is opened which allows the floodwater to be safely diverted past west Melchester.
No opposition whatsoever from local residents, although the nearby main road will need to be closed during construction.
Some high quality farmland to the south-west of Melchester will also be lost.

26. 3. Melchester drain by pass
Total Cost = £ 12.0 million
A large underground tunnel offering a more direct escape route for floodwater from the River Falmer.
At times of high water, the tunnel is opened diverting water from the meanders near the town centre.
Little environmental impact but local residents concerned about possible damage to houses caused by tunnel excavation.

27. 4. Falmer Ring Dyke Total Cost = £ 15.0 million
A massive ringed embankment around the Falmer Levels which would allow floodwaters from the River Falmer and the River Dank to be held back, protecting all of Melchester.
Would cause significant damage to the environment during construction due to the amount of earth that would need to be moved.
It is expected to fill only once every 200 years.
People living in north Melchester are likely to be upset by the noise from all the earth moving machinery required.

28. 5 Swinford temporary basin
Total Cost = £ 5.0 million
Removable flood walls that can be mounted into place with relatively little warning.
Effective with smaller floods but not high enough to cope with 100 year flood events such as that experienced in 2001.
Little environmental impact.
Local residents in Swinford are highly supportive of the proposal although the people of Melchester are concerned that it would merely divert floodwater downstream.

29. 6. Bend Flood Wall Total Cost = £ 5.0 million
A permanent flood wall made from local stone built to protect the village of Bend.
It would also allow access to Bend and Narrowbridge during times of flood when the main road is blocked.
Effective with smaller floods but not high enough to cope with 100 year flood events such as that experienced in 2001.
Local residents in Bend are highly supportive of the proposal although the Bridgefordshire Tourist Board is concerned that it will ruin the lovely scenic views.