At the start of this year, I wrote a brief post on how we’ve been looking closely at the emergence of HTML5 as a visualisation platform. This week, we’ve published the first fruit of those labours – an interactive flow map of internal migration data for England & Wales:

Migration flowmap of England & Wales

The aim here was to really stretch the technology and give it a tough visualisation challenge to see what it’s capable of. The underlying data used in the map contains over 60,000 migration flows – yet we have still managed to produce an interactive application that will run on an iPhone.

I will aim to write some more details later on the development process and the good and bad experiences of transitioning from a platform like Flash. But the majority of solutions to our problems came from a general realisation that HTML5 doesn’t really exist at all, but is more an amorphous mixture of inter-related technologies and javascript libraries that are becoming increasingly cohesive as a development platform. So – take a bow jQuery and Modernizr – these libraries in particular have really helped us to exploit HTML,SVG,Canvas,CSS, XML and javascript technology in a single, integrated document. There’s a way to go yet, but these initial results are extremely promising.

One other element I’m pleased on with this work is that we went beyond simple visualisation of the flow data here – every time you interact with the map to generate a flow visualisation, the browser performs a test to identify ‘significant’ flows (highlighted in orange, to attract your attention), based on a procedure first suggested in 1977 by Professors Peter Hagget and John Holmes. The speed with which that test is performed is real testimony to the improvements in javascript performance made by web browser developers in recent years. That we are now able to perform near real-time tests on statistical data of this volume in a web browser raises another interesting suggestion – that the key to many exciting visualisation challenges might lie in re-examining the past…