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30 Day Map Challenge All Featured Ireland Maps OpenStreetMap OSGEO QGIS Scotland

30 Day Map Challenge 2021

This November I once again took part in the 30 Day Map Challenge started by Topi Tjukanov.

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I had done it the first year (30 Day Map Challenge 2019), and had made a few maps for 2020 as well.

This year I wasn’t really sure I would take part, as I had no plans and nothing prepared. But it is a great challenge. It challenges your creativity, problem solving, and map making skills. It also sets a time limit so you don’t have to worry about being perfect. And making maps is good fun.

There were a few datasets that I had come across that I thought would be good subjects, and I got a lot of mileage out of them.

Dublin neighbourhoods

These included the Dublin Inquirer neighbourhood survey.

Will You Draw Your Dublin Neighbourhood for Us?

neighbourhoods.dublininquirer.com

I think this is a great initiative, and hopefully they get a real large set of responses. They are at over 2000 already so a great start.

I did something similar for Glasgow (here) but only got 367 responses in total. So the power of having a well read paper behind the initiative is great. They are also reaching out to areas that have not had many responses, which is really great work.

OpenStreetMap

I also wanted to do some maps around OpenStreetMap in Ireland. The community here has had a large push to map all of the buildings in Ireland, which has progressed well.

But it is very much a work in progress.

OSM Ireland Buildings poster from State Of The Map 2021

Selected Maps

Hexagons:

Hex

First of the Dublin boundaries series.

Final interactive version: Here

OpenStreetMap:

OpenStreetMap

For OSM day I wanted to try and make the data a bit easier to use for #QGIS novices.

I created styles that can be applied to the GEOFABRIK Shapefile extracts, from here.

The styles are available: https://github.com/HeikkiVesanto/QGIS_OSM_Styles

Red:

Red

Mac vs Mc.

Supermac’s is an Irish fast food restaurant chain, who have had a few trademark disputes over the years with McDonald’s over the use of Mc and Mac in burger names.

3D:

3D

This turned out a lot better than I expected.

Was pure QGIS. Create grid (5km x 5km), zonal statistics on CORINE (Majority) and DEM (Median). New field for height rounded up to the nearest 40:

to_int(ceil((“_h_median” / 40))) * 40

Set colors. Create centroids with same colors. These become the Lego nubs.

Rendered in QGIS2threejs plugin. The grid is extruded, with a height of height * 50. The centroids are cylinder rendered height * 50 + 30 * 50, so they come a bit higher, radius of 1800.

The “rayshader” export makes it look realistic.

Interactive: https://maps.gisforthought.com/LegoIreland/

Might be better to not use landuse, but elevation for the colours.

No Computer:

No Computer

Nice to get away from the computer. Definitely promotes some creativity. But I just took it as an opportunity to walk on the beach.

Land:

Land

My favourite of my maps.

Land use vineyard across Europe from CORINE 2020, with the major regions labelled.

GHSL:

GHSL

Seasonal population of the Balearic Islands.

Data clipping in QGIS/GDAL, rendered in Aerialod, with labels with GIMP afterwards.

This was my second favourite of my maps. I think the topic is interesting and the execution is pretty good. Was however quite manual and probably needed more exaggeration to see the differences.

Historical:

Historical

A time lapse of 1,831,044 buildings in Ireland being added to OpenStreetMap.

If you want to get involved see: OpenStreetMap Ireland Buildings

Globe:

Globe

Simple spinning globe in QGIS, but I was happy that I was able to automate the export: Gist

All maps:

See here

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All Featured Ireland Maps OSGEO PostGIS QGIS Scotland

Every Person in Great Britain Mapped

A follow up to my previous post: Every Person in Scotland on the Map. Winner of the 2016 OS OpenData Award for Excellence in the use of OpenData from the British Cartographic Society.

Full size interactive map.

The mapping process is pretty straightforward, and not accurate. I don’t know where you live. But I can make an educated guess.

I simply amalgamate the two sets of census data from the NRS (National Records of Scotland) for Scotland (2011 census) and the ONS (Office of National Statistics) for England and Wales (2010 census).

Postcodes were then created based on the ONS Postcode Directory, filtering for postcodes that were live in 2011 (which is the latest census data). The postcode centroids were turned into polygons using voronoi polygons.

Then we simply select all of the buildings in a postcode from Ordnance SurveyOpen Map product, filtering out most schools and hospitals. Then we put a random point in a random building for each person in that postcode.

I would have loved to include Northern Ireland, but the Ordnance Survey of Northern Ireland do not have an equivalent open building outline dataset, like Open Map from the Ordnance Survey.

Rendered with: QGIS tile writer python script. Processing done 100% in PostGIS.

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All Scotland

Crowdsourced City Extents

Following up from my Glasgow Regions Mapped Update.

Alasdair Rae recently started a crowdsourcing project for four cities in the UK: London, Birmingham, Manchester, and Glasgow. Original page. Write up of the results. The post was however very popular and resulted in responses from around the world.

Since the project was created with the excellent code from Nick Martinelli, the data can be downloaded by anyone.

So I created a breakdown of the number of responses in 1 km grids for each city that received at least 5 responses.

The full album, ordered by country name and then city name can be found:

Here.

Highlights

Glasgow

The west end is the true Glasgow.
UnitedKingdom_Glasgow_extents46

Edinburgh

Very inclusive.
UnitedKingdom_Edinburgh_extents33

Liverpool

Much larger and inclusive than Manchester.
UnitedKingdom_Liverpool_extents20

London

The M25 provides a very handy limiting barrier.
UnitedKingdom_London_extents29

LA

Far reaching urban sprawl.
UnitedStatesofAmerica_LosAngeles_extents10

New York

Probably some selection bias, with crowd sourcing more popular in Brooklyn.
UnitedStatesofAmerica_NewYork_extents32

Washington

DC.
UnitedStatesofAmerica_Washington_extents21

All cities.

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All Maps Scotland

Glasgow Regions Mapped – Progress Update 1

You can read the initial post at: Mapping Glasgow Districts

We have had some great progress on the mapping so far. There have been 367 regions mapped to date. However, as mentioned in the original post, there are a huge number of regions in Glasgow so even with over 300 responses many regions have only one response and others are still unmapped. But in the hopes of encouraging some more responses I felt it would be nice to show what progress has been made to date.

Statistics so far:
Unique region names so far: 241

Most mapped regions:
City Centre – 10
Finnieston – 9
Merchant City – 9
Dennistoun – 8
Partick – 7
West End – 7
Garnethill – 6
Hyndland – 6
Woodlands – 5
Hillhead – 5
Mount Florida – 5

Regions so far. Click for PDF version.
map_so_far

We can see that there are still quite a few regions that have had the same number of responses with multiple region names.

We can look at what these responses have been, in an interactive map:


Full Screen.

We can see that the West End in general has been the target of a large number of responses, so we can drill in a little further:

west_end1

Extent of the west end:

West End

Individual regions:

Anderston

Anniesland

Blairdardie

Broomhill

Charing Cross

Dowanhill

Drumchapel

Finnieston

Firhill

Garrioch

Hillhead

Hyndland

Jordanhill

Kelvingrove Park

Knightswood

Maryhill

Not Partick

Park Circus

Partick

Partickhill

Scotstoun

Thornwood

West Maryhill

Whiteinch

Woodlands

Yoker

Yorkhill

A final note, there have been some creative responses as well, as expected. But the flagging system on the mapping page has worked incredibly well.

A huge thanks if you have responded already. I would be grateful if you could share this on either Facebook, Twitter, or anywhere else. The more responses that are submitted, the better the end result.

Happy to take on suggestions as well.

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All Maps OSGEO QGIS Scotland

Every Person in Scotland on the Map

Winner of the 2016 OS OpenData Award for Excellence in the use of OpenData from the British Cartographic Society.

Full size.

The mapping process creates a random point within a building shell inside of a postcode area, which is repeated for every person in a postcode. This is in contrast to a simpler process, which does not take into account buildings at all, working simply with postcode areas. This can be seen in my previous post: Population of Scotland Mapped

Inspired by:
The Guardian – Every person in England and Wales on a map by Chris Cross

Based on the 2011 Scottish Census population data.

Data from the National Records of Scotland.

Combined with the Ordnance Survey, Open Map product.

Rendered with: QGIS tile writer python script.

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All Maps Scotland

Forth Road Bridge Closure Impact on Drive Times

In honour of the Forth Road Bridge re-opening completely. I created a map of the impact it has had on drive times from Edinburgh.

This is based on the OS Open Roads Product, using pgRouting, and network generated using the guide from Ross McDonald.

This does not take into account the increase of traffic on the other routes, or traffic in general. Would be interesting to see a real impact map from one of the major navigation providers.

Drive time with and without the forth road bridge

Difference the forth road bridge closue caused map

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All Scotland

Mapping Glasgow Districts

First update: Glasgow Regions Mapped – Progress Update 1

Lets map the districts/regions/neighbourhoods/suburbs of Glasgow. The divisions of a city can be hard to distinguish, there are no hard boundaries between regions and these can be dynamic over time. Where does the West End begin? As soon as you cross the M8, or later? Where does the West End end? Before Partick, halfway through, or well past Scotstoun? Have your say!

People Make Glasgow, help define its boundaries.

This was done successfully in Boston: Bostonography – Neighborhoods as seen by the people.

Although Boston is a significantly easier target. Their map covered 21 different neighbourhoods. According to Wikipedia, Glasgow has at least 145 districts.

This will only be significant if we get a good number of responses. So please feel free to share!

Made possible by: Nick Martinelli from extent(PNW). Code on GitHub.

Map Glasgow’s Regions.

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All Scotland Travel

The Great Polish Map of Scotland Revisited

A lot of progress has been made since my last visit: Visiting the Great Polish Map of Scotland

This time I had a bit more time, staying overnight with the very accomodating girlfirend at the Barony Castle Hotel. The steak was excellent, but the sauna was not very hot. Overall a good experience though.

PANO_20151031_145802

PANO_20151031_145722

PANO_20151031_145635

As you can see from the photos restoration works are in full progress.

IMG_20151101_110954

And dontains can be made to the worthy cause at: MapaScotland.org

IMG_20151031_152433

For a view of the way up to the map, see my first post on Mapillary:

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All OSGEO PostGIS QGIS Scotland

Multi Ring Buffer – Buffer the Buffer or Incrementally Increasing Distance?

Does it matter, and who cares?

Multi-ring buffers can be useful for simple distance calculations as seen in:
X Percent of the Population of Scotland Lives Within Y Miles of Glasgow
And:
X Percent of the Population of Scotland Lives Within Y Miles of Edinburgh

For these I simply created multiple buffers using the QGIS buffer tool. This works for small samples, but was quite frustrating. I had initially hoped to do the whole analysis in SQLite, which worked pretty well initally, but struggled on the larger buffers. It took too long to run the queries, and did not allow for visualisation. I think using PostGIS would however be pretty feasible.

But creating a multi-ring buffer plugin for QGIS also seemed like a good learning experience. Which got me thinking, does it matter if you create increasingly large buffers around the original feature, or if you buffered the resulting buffer sequentially. My hypothesis was that there would be pretty significant differences due to the rounding of corners.

I asked on StackExchange but the conversation did not really take off:
http://gis.stackexchange.com/questions/140413/multi-ring-buffer-methodology

My question is not about the overlapping-ness of the buffers, since I think multi-ring buffers should be “doughnuts” anyway. But rather if smoothing will occur. The only answer was to try it myself.

Buffer styles:
Buffer the resulting buffer sequentially: Sequential
Buffer the original feature with increasing buffer distance: Central
[table caption=”Speed – In seconds”]
Features, Rings,Central, Sequential
1, 5, 0.59, 0.56
55, 5, 8.06, 6.38
1, 200, 60.83, 31.76
3, 200, 62.89, 40.89
55, 200, 628.38, 586.67
1, 2000, 203.84, 67.00
[/table]

No matter how you do it the sequential style is quicker, but that may be down to my code.

Rendering

Interestingly, although understandably, the sequential style results in a lot more vertices in the outer rings. For comparison, for a 500 ring buffer the outermost ring had the following vertice counts:
[table]
Style, Vertices
Central,488
Sequential,30918
[/table]

We can see this with editing turned on.
Central:
Central_editing
Sequential:
Sequential_editing

We can also see a smoother profile in the sequential buffer. However the difference is not major, and hard to discern with the naked eye.

So we have at most about around a 10m discrepancy, with 500 50m rings, so around 25000m of distance from the original feature.
Screenshot[34]
This impacts rendering time dramatically, an example with our 500 rings:

Central:

Sequential:

So quicker to create but slower to draw. So which one is better, quicker calculation, or quicker rendering? Or should we not do 200+ ring buffers?

Hard to say. In version 0.2 of the Multi Ring Buffer Plugin. There is an option for either in the advanced tab.

Plugin: https://plugins.qgis.org/plugins/Multi_Ring_Buffer/
Please report any issues through GitHub: https://github.com/HeikkiVesanto/QGIS_Multi_Ring_Buffer/issues

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All Featured Scotland Travel

Schiehallion – Contour lines and Maskelyne’s observatory

In 1774 large science was taking place in the heart of Scotland. Two men were about to weigh the earth. This was done using plumblines and measuring how much the hill in Perthshire, called Schiehallion, displaced them. Schiehallion was chosen for its uniform appearance and relative accessibility.

The two people responsible for the experiment were the astronomer Nevil Maskelyne and the surveyor Charles Hutton. Charles Hutton, in order to make calculations of the volume of the mountain, pioneered the use of contour lines. These were essential in joining up measurement points to create a continual observation. Maskelyne set up a cabin on each side of the mountain where he could live and take astronomical observations and plumbline readings. The hut on the north side of the mountain famously burned down during the whisky fuelled celebrations of completing the observations, taking with it a local boys precious fiddle. Upon returning to London Maskelyne compensated the boys loss by sending him a replacement fiddle, a Stradivarius.

A good account of the Scheihallion experiment can be found in Rachel Hewitt’s: Map of a Nation. Which also provides an excellent account of the early days of the Ordnance Survey.

My goal for the trip was to find the remains of Maskelyne’s ruined observatory, which according to some reports could still be found on the northern slopes of the mountain. The quest was inspired by Simon Ingram. Whose account of climbing Schiehallion in Between the Sunset and the Sea is definitely worth a read. I used the notes found in that book to narrow the search area.

Also available for free from Audible: Free 30 day trial

I set off, driving past Dull (Paired with Boring, Oregon), which was not a sign of how the day would turn out.

Dull and Boring

The first views of Schiehallion do not show the characteristic conical shape, rather a gradual slope.

First glimpse

However the uniformity can be seen in the historic Ordnance Survey maps:

UK Great Britain, Ordnance Survey one-inch to the mile (1:63,360), ‘Hills’ edition, 1885-1903 National Library of Scotland:

UK Great Britain, Ordnance Survey (1:1 million-1:10,560), 1900s from the National Library of Scotland:

UK Ordnance Survey Historical Maps from 1919-1947 National Library of Scotland:

UK Great Britain, Ordnance Survey One-Inch Seventh Series (1:63,360), 1955-1961 National Library of Scotland:

At the head of the car park there is a memorial to the observation work that took place on the hill.

Monument

Schiehallion from the car park (parking is £2, and only coins are accepted), with a suggestion of nice weather ahead.

Schiehallion

Unfortunately the weather in Scotland is never predictable. With hail one minute.

Hail

And sunshine the next.

Sun

View from the top of Schiehallion. My goal was to attain the summit, and on the way down break off from the path and head downslope.

Schiehallion

The remains of the Ordnance Survey trig point at the top of Schiehallion.

OS Trig Point

The view of the northern slope, so the observatory remains would be somewhere down there. There were a couple of promising piles of rocks that could be seen from up high, but upon closer inspection turned out to be… piles of rocks.

Slope

View back up to the ridge.

View back

Northern slope. The terrain was not difficult, but the weather was not ideal.

View down

I was just about the give up the search, but after climbing one final rise I saw a suspiciously uniform pile of rocks.

Finally

The remains of Maskelyne’s observatory. One platform was for the cabin, with the other one for the astronomical instruments.

Maskelyne's observatory

Backpack for scale.

Backpack

A job well done. The way back was very boggy. I took some solace in the fact that I was contouring around the hill that established contour lines. I was also spurred by the success of actually finding the site.

Happy Mapper

Final view back to Schiehallion.

View back

A successful journey, and excellent adventure.

If you want to visit the site I would recommend reading the description in Simon Ingram’s: Between the Sunset and the Sea, and baseing your own search on the description provided.

However I did track my own route, and I had been about to give up my own search before I finally found the site. So my route:

View:

https://gfycat.com/ifr/UnhealthyImpeccableConch

IMG_20151105_205557
As seen in Trail Magazines 2015 October issue-