I recently came back to CartoDB to do a bit of experimenting for some GIS work I'm doing this autumn, so I decided to revisit a topic I looked at before: sub-national regions of the world. In a previous version I posted via Twitter I took sub-national boundaries of the world and put together an interactive map (in about 15 minutes, so it wasn't very good). I've now produced a better one. It's not perfect but I have managed to add in an equal area projection version and other simple features - such as scale-dependent labelling and line styling.
|The Regional World - version 2|
According to Wikipedia, the largest sub-national divisions in the world are the Sakha Republic (Yakutiya) in Russia, Western Australia, and Krasnoyarsk Krai, also in Russia. The first two are more than ten times the size of the UK (which is 244,000 sq km) and number three almost is. If you click on the link above to go to the map then you'll see that you can also click on the equal area version. I did this because web maps often default to the Mercator projection, which causes massive distortion towards the poles and leads people into thinking Greenland is bigger than Africa, which of course it isn't.
|The Regional World - equal area projection|
The equal area projection does of course mean that areas towards the poles are extremely distorted, but that's part of the deal with some map projections. I've taken the administrative boundaries at face value, but of course they may not be 100% accurate, as the authors of the data acknowledge:
"This is the toughest dataset to keep current. Unlike the United States, other countries constantly rearrange their admin-1 units, slicing and combining them on a regular basis."
|Read more about the data|
You'll notice that I have put links to a small number of countries on the main map. I chose these because I find them interesting, that's all. This was part experiment with CartoDB and a little SQL (projection) and CSS (scale-dependent styling), part GIS project, part teaching material, partly driven by my interest in regions more generally, and part pre-holiday wind-down. In relation to the latter, just for fun, I have hidden two little artefacts in the main map that only appear when you zoom to a certain level at two places on earth.
Can you find them?
Answers via Twitter or e-mail...