Mapping With WMS – SNH – John Muir Way

While Web Mapping Services (WMS) are becoming more common, their functionality is limited. They are easier to set up and run than a Web Feature Service (WFS) but are mainly useful for pre-rendered or background mapping.

Scottish Natural Heritage (SNH) provide an extensive amount of datasets as WMS, through their Natural Spaces data store.

I thought it would be interesting to see what kind of result could be achieved using only WMS.

The result is a map of the John Muir Way, which is a long distance walking route in the central belt of Scotland. Apart from the way itself (it was not provided through the WMS), all data is obtained through the SNH WMS. Some styling could be done using the colorize and layer blending options in QGIS.

WMS Mapping

Scottish Independence Referendum 2014, Election Maps in QGIS

As everyone will no doubt have heard, Scotland voted in a referendum on independence on the 18/09/2014. The vote was no, but it presents an excellent opportunity to visualise election results.

Addition From Black

Addition From Black

We start with a black background since in RGB 0,0,0 is pitch black. Then we have 2 datasets with graduated colour scheme from completely transparent to completely red/blue. We use the percentages per council area to show the split, but using absolute counts could also work. These layers have the blending mode of “Addition” so they stack creating a purple map, with the redder areas voting no and the bluer areas voting yes.

Bar Graph

Bar Graph

This is more of a proof of concept than a truly functional map. The bars are created from the polygon centroids as a line symbol. The length of each bar plotted in meters from a calculation of the number of votes * 1000. I found out that this could be more easily created using the diagrams feature, which would produce the same result without the need for creating centroids and allow for more placement options.

Data Driven Opacity and Hue

Data Driven Opacity and Hue

Simple Red to Blue gradient from the percentage of yes votes. So from 30% to 70%, providing a nice gradient of the vote outcome. Above this was place a completely white layer, which had its alpha channel driven by a normalized total voters field. So Glasgow has a white 100% transparent feature over it, while Orkney has a 0% transparent feature. This symbolises the impact of each councils vote and the result.

Scotland’s Connections to the Wider World

On the verge of the Scottish vote for independence here is a look at all of the scheduled passenger connections between Scotland and outside of the UK. As it is, there are only flights. There are a few ferries between Northern Ireland and Scotland, however NI is still within the UK. No conclusions just an interesting visualisation.

Flights from Scotland to outside the UK

Thanks to:

The World Is A Village – PostGIS: using latitude and longitude to create geometry

Anita Graser – Visualizing Global Connections

Data from:

Natural Earth

OpenFlights

Scotland’s Changing Outline

In 1654 Joannis Blaeu published volume 5 of his Atlas Novus. The Atlas contained three general maps of Scotland and 46 maps of Scottish counties or regions, making Scotland the best mapped country in the world.

The Blaeu outline was influential on the outline of Scotland for the next decade to come. This is a comparison of subsequent outlines of Scotland before the 1747-1755 Roy Military Survey of Scotland truly surveyed the whole of Scotland.

The maps in this comparison are:

Excluded is the [1687] – Robert Morden – A mapp of Scotland made by R. Gordon because it essentially just follows the Blaeu outline.

In addition a background map was created from OS BoundaryLine (High Water Polyline) and converted to a polygon.

Everything is converted to WGS 84 / World Mercator projection (EPSG:3395).

For more on how the outlines were created:

Georeferencing vector data

For a history of the maps used:

Historic Maps of Scotland from Blaeu to Dorret (1600-1700)

If you are interested in buying a historically amazing map:

Blaeu Atlas Maior of 1665 – Including the atlas of Scotland.

Scotland’s changing coastline:

Scotlands Changing Coastline