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All Featured Ireland Maps OSGEO PostGIS QGIS

Dublin Neighborhoods Mapped

Neighborhood boundaries are a fascinating topic. Where do people see their neighborhood extending to, how clear are those boundaries, and how do they shift with time.

This is a topic that has been tackled a number of times around the world, and with different types of locations (like cities). With the general public asked to draw their own neighborhood, or the ones they are familiar with, on a map. But there are challenges.

Sometimes the results are successful, like in Boston. Boston only has around 60 neighborhoods, which are relatively clearly defined based on the mapping results. And Bostonography clearly had a great readership, with over 2300 responses.

Older cities, like Glasgow are much more complex. In 2016 I did a similar survey, and from 367 responses I received 241 unique neighborhoods. You would need a much bigger set of responses to come to any real conclusions. But I still mapped the results for the West End of Glasgow, where most neighborhoods had multiple responses: Glasgow Regions Mapped

The challenges for Dublin neighborhoods is similar to Glasgow, although not as complex. But anything worth doing would require a lot of responses.

Luckily the Dublin InQuirer decided to run a similar survey, polling their subscribers for responses. The number of submissions was good, not quite beating the Boston yet, but getting close. 2200 responses and 133 unique neighborhoods mapped. They also did a few great things. One was making the data available to download. This meant that anyone could map the results, which is great. Additionally they are reaching out to areas with less responses, which is a great effort on their part.

Dublin InQuirer – Will You Draw Your Dublin Neighbourhood for Us?

Map your neighborhood.

Results:

I have mapped all of the neighborhoods as an interactive map, and individually if they had 10 or more responses.

Interactive:

Full page.

Individual Dublin Hoods:

The following have been mapped as they had over 10 responses:

Artane,
Baldoyle,
Ballinteer,
Ballsbridge,
Ballybough,
Ballyfermot,
Beaumont,
Blackrock,
Broadstone,
Cabra,
Castleknock,
Churchtown,
Clondalkin,
Clontarf,
Crumlin,
Dolphins Barn,
Donnybrook,
Donnycarney,
Drimnagh,
Drumcondra,
Dun Laoghaire,
East Wall,
Fairview,
Finglas,
Firhouse,
Glasnevin,
Goatstown,
Harold’s Cross,
Inchicore,
Islandbridge,
Kilmainham,
Kimmage,
Knocklyon,
Lower Crumlin,
Lucan,
Malahide,
Marino,
Navanroad,
Phibsborough,
Portmarnock,
Portobello,
Raheny,
Ranelagh,
Rathfarnham,
Rathgar,
Rathmines,
Rialto,
Sandymount,
Santry,
Smithfield,
Stoneybatter,
Sutton,
Tallaght,
Terenure,
The Liberties,
The Tenters,
Whitehall

Creation:

These maps were created with Python for downloading the data, PostgreSQL/PostGIS for the data processing, and QGIS for the rendering.

There is not a full tutorial, but the processing code is available in here:

Downloading the data.

SQL processing.

Categories
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.

Categories

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

Categories
30 Day Map Challenge All Featured Ireland Maps

30 Day Map Challenge 2019

Last November I took part in the 30 Day Map Challenge. An excellent project suggested by Topi Tjukanov on twitter:

I perhaps had a bit of an advantage. I had already completed a very similar challenge in 2014. Mapvember.

Where I made a post on this blog every day for all of November, primarily maps.

Where I made a post on this blog every day for all of November, primarily maps.

And a summary:
https://gisforthought.com/mapvember/

There are a lot of advantages to this style of map creation and a few down sides.

Advantages

  • It puts a time limit on the maps. This forces you to put them out there no matter the status. It is easy to leave maps half finished because they are not perfect. I know the internet can be a harsh critic sometimes, but you are making a map a day, it won’t be perfect.
  • You can revisit some older maps that have been discarded in the past. Perhaps they didn’t look so good, weren’t so interesting. That doesn’t matter, you are posting a map a day they don’t have to be perfect.
  • There are a lot of ideas out there. I use a Google keep note to store map ideas I have. The list keeps on getting longer and without some pushing it never gets shorter.
  • Collaboration. There were some great maps made, and every day you could enjoy them as well, feeling part of the community. Sharing ideas and techniques.
  • Increase your talents. The only way you are going to get better at mapping is by making some maps. No better way to do it than pushing yourself.
  • Work with new data. 30 maps is a lot of maps. You can explore new datasets and new software.
  • Grow your following. As the challenge is on Twitter it is a good way to build your following. I got 139 new followers over the month. Now for some people that isn’t much. But I only have 600 in general so it’s a sizeable amount. Although I’m not sure there is that much value to followers. But 197k impressions is good? 1 follower per 1000 who saw a map.

Disadvantages

30 maps is a lot of maps to make. A day is a short time to make one. My tactic, based on my previous experience, was to make a few upfront and ready to go. So by the time November started I had a few maps ready, so I could be ahead of the curve.

I used tweetdeck to schedule the tweets. I didn’t map on the weekend for the most part. I had other commitments, so scheduling and making some easy maps was crucial to completing the challenge.

There are no real rules to the challenge, interpret it how you wish. Do a map a day, or a map a week, but the important part is enjoying it.

Maps

There is a great website that collects all the maps created by theme and creator:

https://david.frigge.nz/30DayMapChallenge/index.html

I have posted all of my maps here.

With a select few favorites:

Day 1Points – Ireland’s population mapped as one point per person. 6,572,675 points in total:

Day 2Lines – 1 week of flying for Ryanair EI-DYP Boeing 737-800:

Day 5Raster – Total rainfall in Ireland in 2018 from Met Eireann data:

Day 10Black and White – Register of renewed liquor licences: Publican’s Houses Dublin:

Day 19Urban – Perhaps Dublin’s most confused street:

All in all I whole heartedly recommend taking part when November rolls around again.

Categories
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.

Categories
All Animations Featured OSGEO QGIS Tutorials

Storm Harvey QGIS Geometry Generator

Storm Harvey produced some extremely high levels of rainfall. Some areas of Texas received over 50 inches of rain over 9 days.

The National Oceanic and Atmospheric Administration (NOAA) provided some really great real time datasets to map the progress of the storm.

Among these were:
Hourly Precipitation
and
Hurricane Path

From these we can produce a GIF of hourly precipitation:

Hourly precipitation.

And total precipitation:
Hurricane Harvey Total Precipitation

Particularly the hurricane path was possible to create in QGIS using the Atlas Generator, and the excellent new:ish geometry generator. This can be found as an option for any layers symbology, as one of the renderers.

For my map I had a non spatial table that drove my atlas. This was a log table of all of the hours of precipitation I had loaded into my database. So I looped through each entry and showed the corresponding points of hourly precipitation for the corresponding hour. I also had hurricane path data as points for every 6 hours. So I could use the geometry generator to interpolate points in between known points.

While the query ended up being pretty long it is pretty straightforward.

It only needs to be run when the hour being generated does not end with a 00, 06, 12, or 18, because those are the positions I already know.

For the rest I need to generate two points. One for the previously known point, and one for the next known point.

Then I would create a line between those two points, measure the line, and place a point on the line x times one sixth of the way for the start of the line depending on the hour from the last known point.

Overall I am very impressed and happy with the result. With a bit of data defined rotation the storm progress looks great.

line_interpolate_point(
Make_line(
geometry(
case when right(to_string(attribute(@atlas_feature , 'id')),2) IN ('00', '06', '12', '18') then
    get_feature(  @layer_name , 'dtg', attribute(  @atlas_feature , 'id') )
else
    get_feature(  @layer_name , 'dtg',  attribute(  @atlas_feature , 'id') - (attribute(  @atlas_feature , 'id') % 100 % 6  ))
end)
,
geometry(
case
    when right(to_string(attribute(@atlas_feature , 'id')),2) IN ('00', '06', '12') then
        get_feature(  @layer_name , 'dtg', attribute(  @atlas_feature , 'id') + 6 )
    when right(to_string(attribute(@atlas_feature , 'id')),2) IN ('18') then
        get_feature(  @layer_name , 'dtg', attribute(  @atlas_feature , 'id') + 100 - 18 )
    when to_int(right(to_string(attribute(@atlas_feature , 'id')),2)) > 18 then
        get_feature(  @layer_name , 'dtg',  attribute(  @atlas_feature , 'id') - ((attribute(  @atlas_feature , 'id') % 100 % 6)  ) + 100 - 18)
    else
        get_feature(  @layer_name , 'dtg',  attribute(  @atlas_feature , 'id') - ((attribute(  @atlas_feature , 'id') % 100 % 6)  ) + 6)
end)
),
length(Make_line(geometry(
case when right(to_string(attribute(@atlas_feature , 'id')),2) IN ('00', '06', '12', '18') then get_feature(  @layer_name , 'dtg', attribute(  @atlas_feature , 'id') )
else get_feature(  @layer_name , 'dtg',  attribute(  @atlas_feature , 'id') - (attribute(  @atlas_feature , 'id') % 100 % 6  ))
end
)
,
geometry(
case
    when right(to_string(attribute(@atlas_feature , 'id')),2) IN ('00', '06', '12') then
        get_feature(  @layer_name , 'dtg', attribute(  @atlas_feature , 'id') + 6 )
    when right(to_string(attribute(@atlas_feature , 'id')),2) IN ('18') then
        get_feature(  @layer_name , 'dtg', attribute(  @atlas_feature , 'id') + 100 - 18 )
    when to_int(right(to_string(attribute(@atlas_feature , 'id')),2)) > 18 then
        get_feature(  @layer_name , 'dtg',  attribute(  @atlas_feature , 'id') - ((attribute(  @atlas_feature , 'id') % 100 % 6)  ) + 100 - 18)
    else
        get_feature(  @layer_name , 'dtg',  attribute(  @atlas_feature , 'id') - ((attribute(  @atlas_feature , 'id') % 100 % 6)  ) + 6)
end)))
*
((attribute(  @atlas_feature , 'id') % 100 % 6) * 0.16666666666666666))

Categories
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-