QGIS 1: Spatial analysis for beginners
NICAR24, Baltimore
Wesley Stephenson
BBC News
Callum Thomson
BBC News


Getting started

QGIS stands for Quantum Geographic Information System.

It is a powerful and complex piece of mapping software but journalists can get excellent results from a couple of relatively simple functions. It’s useful for data exploration as well as for producing data maps for publication. And it’s open source.

These are the full follow-along instructions from the NICAR session with a worked example.

If you are in the NICAR session, please use the PCs provided as the files are large and are already downloaded. If you are following afterwards, you will find the data and shapefiles here - please download them before starting.

By the end of this tutorial you should have made a map of urban heat islands in the city of Baltimore, complete with markers for significant cities.

It should look something like this:

Opening QGIS

There are lots of versions as it is frequently updated. You can choose between the latest release or the long-term release (LTR) which is more stable.

The version we are using here is QGIS 3.28 LTR. It’s not the most recent version, but it is stable.

TIP Be aware that QGIS projects are not always backwards-compatible so when you update, you may have to rebuild old projects.  

Finding your way around

QGIS should look something like this. It may not be exactly the same, depending on the edition and whether the panels and toolbars have been moved around, but it should have these functions. The version for Windows looks slightly different.

You need two basic ingredients for most QGIS maps - 
1) a shapefile which is the map on which you will display your data. 
2) a data file, usually a CSV, which contains the information you want to display 
(There are other options - for example you can bring in a highly detailed aerial photograph)

Adding a shapefile
When people talk about a shapefile, or you go looking for one, you actually need a collection of files which all correspond to each other. They are often found in zip files.

If you have not already done so, go to the folder for this workshop and find the sub-folder called tl_2023_24_tract and download it. Inside are all the boundary files for the tracts used in the 2020 US Census for the whole state of Maryland.