GIS in the Classroom Blog 10: How can we use GIS to investigate change in population?

‘Demography, demography, demography!’ It’s hard not to overstate the importance of studying population in geography. A good understanding of the dynamics and spatial dimensions of demography seems fundamental for a full understanding of many other topics. In the last decade, the capacity of GIS applications to help visualise demographic data has been nothing short of revelatory. We’ll look at some examples that will be useful for teaching.

Esri’s ‘Teach With GIS UK’ pages include helpful readymade resources on themes of Global Population and UK Population. For further exploration, analysis and use in investigations these data are also available within ArcGIS Online.

Here’s an example of using data available with a free subscription to ArcGIS Online. The median age of countries around the world is shown and the pop-ups have been configured to reveal the trend over time for each country. A chart widget has also been added, enabling interactive comparisons between countries. It includes a ‘spatial filter’ to enable selection of small (or large!) numbers of countries. The demonstration here shows the marked differences in median age for Niger, Libya, Tunisia, France, Malta, and Italy, producing instant column charts, illustrating what appears to show a distinct ‘median gradient’ along a transect between countries in central north Africa and northern Europe. Such spatial comparisons are vital for informing the study of contrasting perspectives on population growth.

We can use freely available and easily accessible GIS viewers look at similar data on a local scale, through to national scale using the recently created apps by The Office for National Statistics, specifically for the visualisation of Census2021. Here is the Census2021 Population Median Age (ONS) showing how simple movement of the cursor over the map can create an instant transect to show media gradient with distance from central London. Some of this data can also be accessed in ArcGIS Online.

There is often an incredible generosity of spirit in the sharing of data visualisation, exemplified particularly well by Martin De Wulf, the creator of PopulationPyramid.net, a website that was an early provider of big data visuals which many teachers and others have used for well over a decade. Around 2017, I asked Martin if he would be happy for me to channel the PopulationPyramid.net charts spatially to show the locations for each country. He kindly agreed to this and I was able to create a map in ArcGIS Online to show the population pyramid for every country and present it through the prism of the Demographic Transition Model (DTM). Understanding the complexities of the model, including its drawbacks can be quite challenging. The tabbed story map supports the management of cognitive load along the way. The tabbed story map, with over 230,000 views to date, supports a stepped approach and narrative about how the DTM works.

Similarly, @EngagingData has produced very useful visualisations, such as ‘Assembling the World Country-By-Country’. The map controls show each country in order of Population Density and interactivity allows control of options such as speed.

There are of course overlaps between population and development. Our World In Data provides an impressive range of accessible, interactive visualisations, including chart and map presentations, together with download options as well. Here is an interesting way to study spatiotemporal changes in life expectancy, winding the clock back to the 1940s for most countries, the eighteenth century for a small number of European countries and as far back as 1543! Watch out for the year when life expectancy in the UK plunged to 22.4 years.