GIS: A Tool for Visualizing Data with a Geographic Element (Location Matters!)

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(Disponible en français: Les systèmes d’information géographique (SIG) : des outils de visualisation de données associées à un emplacement géographique (la localisation, c’est important!))

“…if some countries have too much history, we have too much geography”: Former Prime Minister William Lyon Mackenzie King.[1]

A single map can convey information. But if you layer various datasets on top of each other on the map, and then compare the data, you may discover patterns and relationships not otherwise readily apparent.

In recent years, the Library of Parliament has employed Geographic Information Systems (GIS) to support research and communicate analysis through its Parliamentary Information and Research Service (PIRS) publications.

The Library’s implementation of GIS has evolved over time as authoritative geographic datasets have become available. Sources of these datasets include Natural Resources Canada’s (NRCan’s) GeoGratis, Canada’s Open Government Portal, Open Maps, Statistics Canada’s geographic data, and international data sources such as the UN, WHO Health Atlas, and U.S. Government Open Data.

What is GIS?

If you have used Google Maps; consulted a public transit planner; explored a real estate search tool; or perused a weekly flyer delivered to an address, then you have employed a tool or product administered by a GIS.

A GIS is broadly defined as a tool combining computer hardware and commercial or open source software that supports techniques from Geomatics and Geographic Information Science (GIScience).[2][3]

A GIS supports collection, storage, maintenance and visualization of spatial data – physical or other observations – linked to a specific location on the earth by a coordinate system of longitude or latitude, or by another reference system, such as an address or postal code or other reference system.

Figure 1 – How GIS models the real world, and facilitates layering different data sets on top of each other for analysis.

Figure 1 illustrates how point, line and area (polygon) layers in a GIS can be used to model real world phenomena. The graph contains a globe on the left, centered on North America and containing the outline of one small square area around Ottawa, Ontario, Canada. Hatched lines tie that defined area on the globe to a zoomed-in section of a flat street map showing the downtown core. The flat map is separated into several individual layers appearing above the street map in a column. These layers are the individual components of the map: location points, rail and road lines, building, vegetation, residential, water and province areas.

Source: Figure prepared by author, Ottawa, 2016, using data Natural Resources Canada, Canvec +, 2015. The following software was used: Esri, ArcGIS, version 10.3.1. Contains information licensed under Open Government Licence – Canada.

GIS: a Canadian creation

In the 1960s, the monumental task of mapping the agricultural potential of Canada’s vast and largely uninhabited lands led English geographer Dr. Roger Tomlinson to develop the first computer mapping system for the Canada Land Inventory (CLI).[4]

Dr. Tomlinson, who introduced the term Canada Geographic Information System, was appointed to the Order of Canada in 2001 for “changing the face of geography as a discipline”.

Shortly thereafter, developments were seen in Canada for a National Mapping Project. In the United States, the U.S. Census Bureau produced digital records for all the nation’s streets during the 1970 Census of Population. Simultaneously, the British Geological Survey produced a series of digital maps, while Canada, Australia, France and the United States continued exploring the use of computers to produce and edit maps.[5]

Canada’s current geospatial infrastructure is comprised of the GeoConnections division of NRCan, which leads the Canadian Geospatial Data Infrastructure (CGDI) in overseeing standards of practice for all departments using GIS.

The Federal Committee on Geomatics and Earth Observations (FCGEO) was instrumental in implementing the new Federal Geospatial Platform, a collaborative government online repository of authoritative geospatial data, online services and applications.

Figure 2 – How data in a table is linked to spatial features.

Figure 2 is an example of how a GIS dynamically connects features in a map layer to a table of data that can be queried. The image shows continuous and adjacent areas (polygons) of census dissemination areas in the center of Winnipeg, MA. When one area is selected, the information associated to that specific location may be identified and a table showing that record among all other records can simultaneously be accessed.

Source: Figure prepared by author, Ottawa, 2016, using data from Statistics Canada, 2011 Census – Dissemination Area Cartographic Boundary Files; and Statistics Canada, Table 98-316-XWE2011001-1501, “Dissemination Area Census Profile”, 2011. The following software was used: Esri, ArcGIS, version 10.3.1. Contains information licensed under Open Government Licence – Canada.

The analytical power of GIS

GIS can link large amounts of data to locations on a map (Fig. 2).

The power of GIS lies in analyzing layers to reveal patterns and relationships that are not easily discernible in spreadsheets or tables.[6] It enables place-based decision- making to inform policy and improve government services.[7]

GIS techniques

Techniques used in GIS include cartography, geodesy, remote sensing (using data from satellite images, aerial photos, geophysical surveys (see “Geophysics” in list)), spatial analysis (predictive modelling, analysis in public health, logistic or supply-chain monitoring) and spatial statistics.

GIS products

GIS applications can yield a wide range of results. They are most commonly grouped into three types of map products and web mapping services (Figure 3):

1- reference maps;

2- thematic maps: maps showing the spatial distribution of data themes including demographic, economic and natural resource data related to forestry, mining, transportation, energy, water resources, etc.; and

3- topographic maps: highly accurate maps representing natural and human-made features on the ground.

Map portals or web mapping services support interactive exploration and basic analysis of data layers.

Figure 3 – Thematic, Reference and Topographic maps.

Figure 3 contains five map examples to illustrate the different map types. There are three thematic maps: one world map showing percent voter turnout; one world map showing the terrorism index and a comparative map showing immigration in Canada in 1911 and 2011. There is one reference map of Canada showing the main rail and road systems as well as provincial and national capitals; and one topographic map showing elevation, road, rail, water and landmarks of interest.

Source: Map examples from Library of Parliament HillNotes publications on Electoral Reform, Counter-Terrorism, Diversity in Canada; a legislative summary on Bill C-74; and Natural Resources Canada, The Atlas of Canada – Toporama web map service. The following software was used: Esri, ArcGIS, version 10.3.1.Contains information licensed under Open Government Licence – Canada

Myriad users of GIS

Forestry, oil and gas, and agricultural industries have long employed GIS in resource and supply chain management, while colleges and universities possess strong GIS curricula and GIS research in several academic fields. The use of GIS is also pervasive across all levels of government.[8]

It is used for inventory applications, decision-making and policy analysis, and to answer questions and communicate results across many departments. [9] For instance, GIS can address whether there is a relationship between school enrolment and immunization.[10]

Municipal government

Most municipalities use GIS to manage services, utilities and infrastructure (including roads, water treatment and delivery, traffic, policing, public transportation, environmental services, parks, community services and so on).

They also use it to communicate public information via open data portals, with data or interactive maps, as those of Québec [available in French only] or Vancouver, and with analytical products, as in Edmonton.

Provincial and territorial governments

Many provincial and territorial GIS data portals provide access to underlying data used to manage, monitor and analyze natural resources, transportation, education, social services, health and safety and emergency response.

GIS can serve as the underlying application to monitor and predict water quality, convey community health statistics , identify public services or in forest fire emergency management.

Federal government

The military adopted practical applications of GIS early, using it to enhance mission details and terrain mapping. Emergency management lent itself to using GIS to manage inventories of key exit routes, traffic issues, emergency facilities and danger areas.[11]

Most federal departments have adopted GIS for data management and analysis. This has resulted in production of maps on topics related to agriculture, defence, demographics, economics, electoral ridings, employment, energy, fisheries, health risks, public safety, transportation (see 2014, Annex A Cartography in the link), weather prediction and others.

Many spatial data portals have been developed to communicate results to Canadians, including:

Indeed, when Canada’s Open Data portal was launched in March 2011, more than 90% of the data were comprised of Natural Resources Canada’s (NRCan) spatial data. GIS now maintains a solid role in evidence-based policy research.

Emerging trends

The advent of the Internet prompted deployment of geographic data as interactive map images. Open government Maps, or privately hosted interactive map services, allow users to search, explore and query geographic data in a cloud environment and receive real-time GIS updates, particularly in relation to traffic and weather maps.

Web 2.0, and the release of more open data, encourage collaborative GIS in which individuals using mobile applications and GPS-enabled devices may create mash-ups of their data overlaid on publicly available base maps.[12]

Emerging technologies and experimentation in virtual reality and cyber cartography are improving 3D and 4D (time) representations.

Further reading

Chang, Kang-Tsung. Introduction to Geographic Information. 8th ed., McGraw-Hill Education, New York, 2016.

Peterson, Gretchen N. GIS Cartography : A Guide to Effective Map Design. 2nd ed. CRC Press, Boca Raton, FL, 2014.

Tomlinson, Roger. Thinking About GIS: Geographic Information System Planning for Managers. 5th ed., ESRI Press, Redlands, California, 2011.

Author: Melanie Zahab, Library of Parliament

[1] House of Commons, Debates, 1st Session, 18th Parliament, 18 June, 1936, pp. 3868.  As noted from Statistics Canada archived content on Geography.

[2] Heywood, et al.  An Introduction to Geographical Information Systems, 4th ed., Prentice Hall, Harlow, England, 2011, p. 18.

[3] Slocum, T. et al. Thematic Cartography and Geovisualization, 3rd ed., Prentice Hall, Upper Saddle River, NJ, 2009, p. 14.

[4] Longley, et al., Geographic Information Systems & Science, 3rd ed., Wiley, Hoboken NJ, 2011, p.368.

Barnes, Trevor J., “The Geographical State:  The Development of Canadian Geography”, Journal of Geography in Higher Education, Vol. 31, No. 1, 2007, p. 172.

[5] Ibid. (Longley), p. 17.

[6] Fu, Pinde.  Web GIS:  Principles and Applications, 1st Edition, ESRI Press, Redlands, California, 2011.

[7] Thomas, C. and H. Warren.  Mapping the Nation: GIS for Federal Progress and Accountability, ESRI Press, Redlands, Calif., 2011.

[8] Bossler, J.D., ed., Manual of Geospatial Science and Technology, 2nd ed., CRC Press, Taylor and Francis, New York NY, p.714.

[9] Longley, et al., Geographic Information Systems & Science, 3rd ed., Wiley, Hoboken NJ, 2011, p. 43

Natural Resources Canada: “CGDI in Action: Geomatics – Improving our everyday world – Video”, Accessed September 19, 2016.

[10] Gassie, L. and Fisher H. “Developing Sustainable Geographic Information System (GIS) Services for Parliamentary Clients”, IFLA WLIC, Singapore, 2013, p. 4.

[11] Ganapati, Skumar. “Use of Public Participation Geographic Information Systems Applications in E-Government.”, Public Administration Review, May/June 2011, p. 426.

[12] Li, S and J. Gong. “Mashup: A New Way of Providing Web Mapping/GIS Services”, The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol. XXXVII.  Part B4, Beijing, 2008.

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