The WorldPop Demographic Portal is an interactive platform which visualises global population data, together with an AI assistant that enables these data to be explored using text queries in any language. Developed by leading research group WorldPop, based at the University of Southampton, the platform allows users to explore high-resolution spatial demographic data around the world, including changes from 2015 – 2030 without needing specialist skills or software.
In this interview, we speak to Professor Andy Tatem, Director of WorldPop, about the tool and how it can help improve accessibility, allowing more people to access and understand population data.
What story does this visualisation tell?
The Portal shows how population patterns vary significantly both within and between countries and cities. It reveals the changing demographics of our planet over time, showing differences in factors such as age and gender.
Why was it created?
The Portal was developed to help people better understand population change and distributions globally. While discussions about demographics are often focused on national trends, significant variations can exist within countries, cities and communities. The map visualises these differences, allowing users to explore population patterns in greater detail, particularly for low- and middle-income countries.
The Portal was also developed to make our extensive population data more accessible. Much of WorldPop’s data can be complex and require advanced data skills to analyse. The Portal enables a wider audience who may not have technical GIS or data skills to explore, query in their native language and interact with the data, uncovering insights into the changing demographics of our planet.
Finally, the portal supports evidence-based decision-making. By helping users understand where people live and identify population variations and vulnerabilities, it provides valuable insights for policymakers, planners and organisations seeking to target resources and services more effectively.
Who was it created for?
We developed the Portal for a wide range of users who all use population data for different purposes. This includes researchers and academics, who use the data to assess populations at risk from disease, climate change, natural hazards and conflict.
Governments may also use the Portal to inform policy development, resource allocation and planning decisions, while commercial organisations could use the data to support infrastructure planning, from electrification projects to mobile network coverage in remote areas.
Finally, we developed the Portal for people to explore population patterns and trends around the world without requiring specialist GIS expertise.
Tell us how you sourced, analysed and presented the data?
We first combined hundreds of datasets from a range of sources, including national population and housing censuses, administrative boundary data, UN estimates, surveys, migration records and displacement data, to map populations at subnational scales from 2015–2030.
In countries where recent census data were unavailable, missing information was supplemented using satellite imagery, building footprints, land cover and night-time light data to help identify where people are likely to live. Demographic models were then used to fill remaining gaps and create a consistent population dataset over time.
The data was analysed using machine learning and statistical models, which redistributed population totals from larger administrative areas into 100 × 100 metre grid cells.
We then used a combination of QGIS, ArcGIS and WorldPop tools to process, analyse and visualise the population data.
Why did you choose to present the data in this way over other approaches?
We chose an interactive web map, which includes features such as zooming, panning and data selection, allowing users to explore population data at different scales and engage directly with the information.
To ensure the Portal remained accessible to as many users as possible, we displayed the data at administrative unit level. Although the population estimates are produced at a 100 × 100 metre resolution, displaying this level of detail globally would require significant computing power and internet bandwidth.
To support different user needs and improve accessibility, population data for each area was presented alongside population pyramids and line graphs. These allow users to explore demographic patterns and trends over time, complementing the map and providing multiple ways to engage with the data.
We also included an AI-powered, multilingual assistant, allowing users to query and have conversations about the data in any language. This helps make complex demographic data more accessible to a wider audience, including those with limited GIS expertise.
What impact has the visualisation had in research, policy or other contexts?
Our data have already supported a wide range of research, policy and operational applications around the world. For example, it has been used in health information systems in more than 100 countries, contributed to UN health metrics reporting, and helped organisations rapidly calculate population exposure, vulnerability and aid needs in disasters or conflict.
Whilst the Portal is a relatively new tool, it has already received positive feedback from a range of users. We are also working with partners who are interested in incorporating the portal into training programmes and capacity-building activities.
Looking ahead, the portal will be showcased to UN groups and other stakeholders to demonstrate its functionality and explore how it can support decision-making, planning and research.
How else might this approach or data be used?
The Portal will be a valuable educational resource for schools, universities and training programmes, enabling students and practitioners to explore real-world demographic data through an interactive and accessible platform.
Decision-makers working in policy can use the portal to quickly explore population patterns and identify trends or vulnerabilities without requiring specialist GIS skills, helping to support faster and more informed planning and policy decisions.
In addition, we hope to integrate the portal with wider learning and capacity-building initiatives, including WorldPop’s upcoming learning management system and community of practice. This would allow users to share knowledge, learn from one another and develop new applications for geospatial population data.
What steps can others take to try this visualisation technique?
There are a range of free tools available to get started with visualising data, such as Google Earth Engine and QGIS. We also have a range of datasets and tools that users can explore.
The key is to experiment and focus on how the visualisation helps communicate the story behind the data.
To finish with, what’s your one top tip for geographers looking to visualise data in this way?
Understand your data before visualising it. Be critical about where it comes from and its limitations. AI and other tools can help make analysis more accessible, but they should complement, not replace, a strong understanding of the data.