This is a dot density map of religious identity across Greater London. Using data from the 2011 Census, I was able to represent each person as a single dot - that's almost 7 million for London alone! I applied colour to reveal religious allegiance, making the map a multivariate dot density.
Dot density maps are really effective at normalising data by geographic area. This is because places with fewer people fade away, while densely populated areas become more prominent. These visualisations help to reveal hidden patterns, or in this case, communities. They not only look interesting, but help to make the data more meaningful.
Historically, London has been predominantly Christian. This is evident as the map is a sea of blue. Islam, London's second largest religion and represented here as turquoise, seems to have a greater following north of the River Thames. The map also reveals large Jewish, Hindu and Sikh communities - all found to the north and west of the capital.
However, there are many other cities outside of London (honestly) where we can use this technique to reveal religious identity. Here's a few I created. Enjoy!
Here’s a map of Lightning Strikes. Using data from the Met Office, I wanted to visualise the locations of every lightning strike to hit the UK and Ireland in 2017.
I opted to aggregate the strike locations (all two hundred and eighty thousand) to a 5km hex grid, making it possible to observe patterns in the data. Most strikes in 2017 were concentrated towards the northern and eastern parts of England, as well as a hot spot of activity in Wales.
Using proportional FireFly symbols, I tried to create a sense of realism with glowing electric blue dots.
I also incorporated a chart, showing the number of strikes over time. While no surprise, most strikes occur in the summer months.
Here’s a cartogram I created for the 2017 UK General Election. So why did I opt for this technique?
In UK General Elections, each constituency elects one MP to the House of Commons. However, their geographic size varies greatly as they are divided up based on the underlying population, with each constituency containing roughly 70,000 people. By using cartograms, we can give each constituency an equal visual weighting.
Prioritising electoral importance over geographic accuracy can have some side-effects. For example,Scotland represents a considerable geographic area yet elects only 59 MPs, compared with 533 in England. The result of this is a very small and odd looking Scotland. Conversely, densely populated areas such as the South East of England bloat and look much larger than they do on a more conventional map.
This cartogram was featured on The Timeswebsiteas part of their General Election coverage. Unlike my previous cartograms, for project I opted for a rhombus over the reliable hexagon. This was purely an aesthetic decision and aligned with The Timeshouse style.
I also created a geographic version allowing readers to toggle between the two maps (turns out there are some who don’t like cartograms).
US Election 2016
Building on the work for the Breixt referendum, when I was asked by The Timesto support their US Presidential Election coverage, I knew we had to use a Cartogram.
In US elections, Presidents are not chosen by a simple popular vote. Instead citizens vote for electors who are pledged to one of the candidates. This is known as the Electoral College.
The College is made up of 538 electors who represent the United States. Each state is allocated a number of electors, based on the size of its population. California has the most with 55 - whereas Wyoming, which has a much smaller population, has only three.
In almost every state, the winner of the popular vote takes all the Electoral College votes. The candidate who gains 270 votes wins the White House.
For the cartogram I created 538 hexagons, one for each electoral college vote. I used a faint white line to divide the hexagons up and used a thicker, more dominant line to group the hexagons by state. This helped readers to understand how ‘electorally important’ each state was.
In addition, I created a choropleth map using the Albers equal-area projection. A simple toggle allowed readers to switch between visualisation type.
I’ve made the Shapefile for this map available as Open Data. Click here to download and create your own maps!
For the Brexit referendum (officially the ‘United Kingdom European Union membership referendum’)I created a cartogram. Cartograms are useful as they prioritise electoral importance over geographic accuracy.
Unlike General Elections, the Brexit referendum votes were reported by Local Authorities rather than Parliamentary Constituencies.
The United Kingdom voted to leave the European Union, by 51.9% for Leave, and 48.1% for Remain.
My cartogram featured at the heart of The Timesreferendum coverage and provided readers with the latest results and analysis.
Cartograms aren’t the easiest of things to create and as such, I have made my Local Authority Hex Cartogram available for download as an Esri Shapefile. You can download if from hereand enrich with your own data!
When you're at the coast and gaze off into the horizon, do you know which countries are directly across the sea from you? I tried to answer this question by creating an animated map.
My inspiration for Coastal views came from exploring Andy Woodruff’s beautiful Beyond the sea maps. I challenged myself to see if I could create something similar for the UK, using only ArcGIS - turns out it was pretty simple!
To learn more about how this visualisation was created, check out my blog post.