Building a new school serving a large number of children in a rural region, monitoring the state of the Amazon rainforests or marking safe roads in a disaster area are all challenges that can be better managed using a → geographic information system (GIS).
GISs capture geographic data that are then enriched and combined with information, organised, analysed and presented in a visually appealing format. For instance, to find the best location for the aforementioned school, a digital map can be connected with demographic data. But how do we collect or access this data to create a relevant map? And what obstacles could we encounter? The following three steps will make it easier for you to start using such systems:
1. GIS STARTER KIT: KNOWING AND ASSESSING RESOURCES
Before starting any GIS activities, you should review existing project resources. These include:
- Hardware: Data capture, analysis and visualisation are all GIS activities that are impossible to carry out if PCs do not have the right performance and memory specifications. Before you get started, you should also consider (and plan into the project budget) whether, for instance, scanners are required to digitalise analogue data, or whether you need GPS devices to collect data yourself if necessary.
- Software: You can acquire GIS software free of charge as → open source software or purchase a program with a licence. Within the software, a database is set up for storing and managing the geodata. The database is accessed to analyse the project-related information and to evaluate, integrate and visualise it. An alternative is WebGIS, for which the software and the data are on a server that can be accessed via the internet. No installation is required. To use the program, however, you need a stable internet connection. The following GIS programs are suitable for use:
- Open Source: QGIS, Open Street Maps
- Proprietär: ArcGis, Manifold System WebGIS: Carto, Mangomap
- Data: Data and the associated database are at the heart of a GIS. However, a GIS will only unleash its full potential for the project if the data are properly linked. A distinction is made between two types of geodata: vector and grid data. Grid data are cell-based data such as aerial photos. They may be compared to paper maps. Vector data are spatial data depicted as dots, lines and polygons and can display multi-dimensional planes. The geodata required depends on the project objective and should be defined in advance. GIS experts can be helpful here.
- Specialists: Many GIS programs include detailed tutorials and thus also offer novices the possibility to perform GIS assessments. Depending on the application, however, specialist, methodological and technical expertise, that may even include programming skills, is required. For this reason, the extent to which GISs will be used in the project should be clarified in advance. You also need to determine whether users have the skills required to operate the systems or do these skills need to be developed?
2. BLANK SPOTS ON THE MAP: HOW DO I OBTAIN THE CORRECT DATA?
No data, no map. Data bring digital maps to life and make them usable. There are different ways to obtain data. It’s important to determine what data is required for the project, and to do so before the project is launched. In addition to geodata (grid and/or vector data), this may involve meta data, for instance, whether buildings have a water connection. For an infrastructure project, this can be important for subsequent analysis. The following section explains where you can find such data:
- Digitalisation of analogue maps: Paper maps and city maps help visualise developments, such as urban sprawl. That’s why it can be useful to digitalise analogue maps. For this purpose, it is helpful to coordinate efforts with official agencies and research and partner institutions, in order to access archives, for example.
- Georeferencing other data: A data set such as scanned blueprints, census data, etc., are assigned a spatial relation. For georeferencing, it is also a good idea to collaborate with research institutions and official agencies to be able to access the data records that are important for the project.
- Geodata generated from remote sensing: Remote sensing involves exploration or measuring of remote objects without making physical contact. Consequently, this includes satellite images, aerial photos taken from aeroplanes, as well as pictures taken by drones. Geodata acquired through remote sensing have huge potential for many issues related to DC. GISs and geodata are primarily used in DC for resource management, environmental monitoring and for integrated rural regional development.
- Using GPS data for field measurement: The Global Positioning System (GPS) is a satellite-based system that spans the entire globe. Special GPS devices are used to collect GPS data for a geoinformation system. Many smartphones also offer GPS functions. With the right app and a stable internet connection (access), smartphones can serve as GPS devices without any other equipment. For instance, for disaster prevention, escape routes can be indicated through GPS markings and emergency corridors can be set up in the event of a disaster. However, GPS measurements are very time-consuming and require precise planning.
- Crowdsourcing: Crowdsourcing can be used to harness the knowledge of a large group of people by means of a public appeal for input. For GIS activities, crowdsourcing can be used to identify transport hubs in a city. To this end, the participants transmit their daily motion profile to the project via GPS. Correlating these points on a city map by means of GIS software makes it possible to create an overall picture of urban transport. This, however, requires willingness on the part of the ‘crowd’. Incentives may be created through gamification.
- Don’t re-invent the wheel: Many data sets have already been created in the context of other projects. For this reason, carrying out detailed research and consulting with partners or government agencies can be highly useful and can save unnecessary work.
3. OBSTACLES AND CHALLENGES
Sustainability: For proprietary software, licences often have to be renewed once they expire. If the owner fails to do so, data sets may be lost which means that progress, and therefore results, will not be documented. To ensure sustainability of the project, you should therefore discuss who will possibly take over responsibility for the licence and renew it as needed. For open-source solutions, there is a risk of the software itself no longer being further developed. The GIS software QGIS has a large community associated with it, however, that helps resolve problems and develop useful plug-ins and add-ons.
Compatibility and standardisation: There is a wide range of GIS file formats. To ensure compatibility, the file formats for the software in use should be tested and used by all project partners in the same way. For larger-scale projects in particular, such as surveying different cities, one file format should be defined as the standard format to ensure long-term compatibility. One option involves the straightforward use of Excel tables that can be read by all GIS programs.
Visualisation: In some cases, the software used may be unable to visualise the data set. If this happens, you should consult a graphic designer, who will ensure that you will be able to present your work in a visually appealing manner.
Data protection: Drone and satellite images, as well as GPS data and the associated motion profiles enable unprecedented insights into people’s personal space. For this reason, the protection of personal data must be ensured through technical and organisational measures taken early on in the development of GIS activities.