Alasdair Rae @undertheraedar Twitter profile

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Alasdair Rae

@undertheraedar

3 years

Here's the final version of the global population density graphic I made, because another one that is circulating was less well defined, and someone cropped NZ off it

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Alasdair Rae

@undertheraedar

4 years

I decided to create a few more European population density renders - you can find more here if you need a break from the doomscrolling:

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Alasdair Rae

@undertheraedar

1 year

Today's map is the final revision of my attempt to split the population of the UK into four roughly equal parts using a big grid and then designate capital cities that nobody would have a problem with 😉

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Alasdair Rae

@undertheraedar

4 months

🥳 @WillDeakin1 has now done a passenger flow map for every station in Britain - all 2,657 of them - you can find them here:

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Alasdair Rae

@undertheraedar

1 year

Okay, some European population density stuff now - starting with the top 100 1km grid squares by population across Europe, based on the most recent Eurostat data - more to follow

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Alasdair Rae

@undertheraedar

1 year

Today's census map shows the most common housing tenure in each local authority in England and Wales 🏡

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Alasdair Rae

@undertheraedar

4 years

How big is the 90 minute public transit commuter zone for London vs San Francisco? This is my attempt to answer the question. Arrival point is central London or downtown SF. So, light areas = you ought to be able to reach central London/downtown SF within 90 minutes.

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Alasdair Rae

@undertheraedar

4 years

I'm getting ready to go back to the West Highlands next week so I thought I'd make a 'will it be raining when I'm in the West Highlands, and will I be able to see Ben Nevis this time, and also do I need my waterproofs?' map

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Alasdair Rae

@undertheraedar

10 months

I always wondered what a population density spike map + political map would look like so I had a go at it (in new version of #aerialod ) and my verdict is: slightly mad, but quite interesting

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Alasdair Rae

@undertheraedar

1 year

How far south do you have to go before you get to 50% of England and Wales living north of the line? Figures always give % of England and Wales population above/below the moving line. (reposting this for anyone who wants to avoid work and learn some essential demography trivia)

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Alasdair Rae

@undertheraedar

4 years

a few of Japan now - definitely one of the most interesting countries in relation to population distribution and density

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Alasdair Rae

@undertheraedar

6 years

Marine traffic around the UK, in maps. Just a bit of summer blog fun, but actually quite interesting. Loads more maps here, including zoomed-in versions:

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Alasdair Rae

@undertheraedar

4 years

and, finally, here's a population density render of the entire world - zoom in, or open the image in another tab/window to see the fine detail here - it comes out quite well even at this scale (this escalated slowly, but I got there in the end🌍)

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Alasdair Rae

@undertheraedar

1 year

Fairly new set of global roads data from Microsoft: 47.8 million km of roads for a huge chunk of the world (note format is tsv) "The data is freely available for download and use under the Open Data Commons Open Database License (ODbL)." #opendata

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Alasdair Rae

@undertheraedar

1 year

The longest straight line in Great Britain (without crossing a public road). Something I've been meaning to investigate for a while - and I get a longer line than the Ordnance Survey one:

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Alasdair Rae

@undertheraedar

9 months

Today's map is all land over 300m in 3D, everything else flat - using Ordnance Survey terrain data, and now I'm googling "highest point in Gloucestershire" to find out what that dot is

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Alasdair Rae

@undertheraedar

1 year

My adventures in population density continue - this time I try to find the maximum population density in the United States, using 2020 Census data - e.g. here's the maximum 1km square I found in each state long read here:

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Alasdair Rae

@undertheraedar

1 year

My adventures in 2021 England and Wales Census data continue into 2023, this time with a look at modal age by local authority and which 'generation' each area fits into (colours and inspiration from @jburnmurdoch here)

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Alasdair Rae

@undertheraedar

4 years

and, as a little experiment, I did one with just spikes - no land. I think this makes it easier to see some places - e.g. check out New Zealand or Hawaii, or even Reykjavík if you look closely.

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Alasdair Rae

@undertheraedar

1 year

trying to make sense of the bigness of the Elizabeth Line so obviously had to move it north and make some maps (using correct geodesic transformation to account for shifting it northwards, obvs)

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Alasdair Rae

@undertheraedar

5 years

My 5 year old son made a quiz for us. It's pretty tough.

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Alasdair Rae

@undertheraedar

4 years

some renders of North American population density now - I think my favourite view here is around the Midwest and Great Lakes

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Alasdair Rae

@undertheraedar

5 years

A UK-wide version of that 'constituency by deprivation' chart. All 650 constituencies, with names. Wanted to see what it looked like, so here it is. Giant version: Notes on the image have source and method. More info here:

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Alasdair Rae

@undertheraedar

2 years

Thanks to @willy_maps idea and code, and a bit of help from @en_dash , I have now made a totally essential spidermap of trig pillars across Great Britain - shows the 8 closest trig pillars to the centre of the screen

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Alasdair Rae

@undertheraedar

1 year

I'll maybe do a European population density megathread soon because I've finished lots of new maps, but in the meantime here are the locations of the top 40 most densely populated square kilometres

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Alasdair Rae

@undertheraedar

1 year

Another very interesting recent England and Wales Census 2021 release is the passport data, so here's a map of % with no passport at MSOA level, will add a couple more below

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Alasdair Rae

@undertheraedar

5 years

English constituencies by winning party in 2017, and level of deprivation on 2019 IMD (update of a similar chart I did in 2015) Data: and [corrected version of earlier tweet]

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Alasdair Rae

@undertheraedar

2 years

Map of the day today is all areas of Great Britain within / not within 10 miles of a railway station, and is Berwick the only lonely circle?

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Alasdair Rae

@undertheraedar

3 years

While I'm waiting for the next round of election results, I decided to update my UK-wide 'deprivation/constituency' chart using new data. It's up to date following the Hartlepool result, and has constituency names on the graphic this time.

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Alasdair Rae

@undertheraedar

3 years

this is the little 'About this print' sheet that goes along with it

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Alasdair Rae

@undertheraedar

1 year

A little data nugget from this week's (very unusual but still useful and interesting) travel to work data, using LSOAs -map on left is areas where 25% or more worked from home in 2011 -map on right is the 2021 version let's wait 10 years and see what happened next

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Alasdair Rae

@undertheraedar

3 years

I've now done a full write up on the 'arterial cities' visuals I've been spamming everyone with: includes 50 British towns and cities, the raw files, plus how to make them

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Alasdair Rae

@undertheraedar

2 years

Trying to make 'Inverness is west of Plymouth' the new 'Bristol is east of Edinburgh', although there are lots to choose from and even though I've checked my map maths I still think some of these can't be right

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Alasdair Rae

@undertheraedar

1 year

I found 140 1km grid squares with more than 30,000 people - this is where they are - distributed quite widely across Spain, with all the French ones in Paris and a few elsewhere - but 89 of them are in Spain

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Alasdair Rae

@undertheraedar

1 year

Today's #30DayMapChallenge theme is "My favourite..." and for some reason I really enjoy exploring elevation data like this to see what the world looks like - plus also check out Spain 👀 (this is an update of a previous map - prize if anyone can guess the elevation cutoff)

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Alasdair Rae

@undertheraedar

7 years

Yes, you do want all of Great Britain's buildings in a massive shapefile set:

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Alasdair Rae

@undertheraedar

2 years

Always wondered when I would get the chance to use this bad geography joke

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Alasdair Rae

@undertheraedar

2 years

I thought it was important, in the spirit of internet mapping and high quality data science, to also do this for Greggs locations - so this one shows the 10 closest Greggs across the UK

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Alasdair Rae

@undertheraedar

1 year

More Census age data today - a little animation of % by single year of age in each local authority. Probably needs a few watches to sink in - lots in here - but the final 10 seconds I find quite sombre, and you'll NEVER guess when lots of people leave home

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Alasdair Rae

@undertheraedar

1 year

With the latest version of qgis2threejs in QGIS you can set your 3D scenes to autoplay in the browser, following any path you like (as you can see I need to work on this!) - here's the live web page example shown in the video #QGIS

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Alasdair Rae

@undertheraedar

1 year

More England and Wales Census data came out this week - health this time - so I took a look at the geography of bad/very bad health (and then overlaid coalfield areas for comparison)

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Alasdair Rae

@undertheraedar

1 year

More map stuff from the Highlands, this time showing the current 42 mile / 1h15m detour to reach Corran because the ferry is broken (500 metres across the Loch, usually) - having a massive impact on journeys west for foreseeable future

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Alasdair Rae

@undertheraedar

4 years

New blog post: 'How to make a 3D population density render for any country in the world' - step-by-step guide, using open data and free software - I also share example files you can use straight away - replicate the image below for any country

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Alasdair Rae

@undertheraedar

4 years

I haven't really got very far with other parts of the world but here's a fairly basic version for the lower 48 in the US, in roughly the same style as the European ones

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Alasdair Rae

@undertheraedar

1 year

Where's the most densely populated square km in the UK, how many people live in it, and what does it look like on the ground? My attempt to answer these questions, in a bit of a long read, with loads of maps:

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Alasdair Rae

@undertheraedar

1 year

All A roads and motorways in Great Britain, in order, for today's #30DayMapChallenge remix finale 🎶 My favourite (but also nemesis) is the A9 but I'm also quite fond of the A66, A82, and the A858, if we're sharing our deepest secrets - yeah the A830 isn't too bad either!

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Alasdair Rae

@undertheraedar

2 years

A little map animated map experiment with Ordnance Survey data - contours are animated at 10 metre intervals, starting at 10 metres above sea level

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Alasdair Rae

@undertheraedar

4 years

I got slightly distracted whilst doing some more sensible population density analysis and this happened - a map and two charts of the UK's population, by 1km grid cell (excuse the slight misalignment on the charts but I was on a deadline for something else)

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Alasdair Rae

@undertheraedar

1 year

May the Forth be with you this year (tweeting three Forth bridges on the fourth day of the fifth month is now traditional)

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Alasdair Rae

@undertheraedar

3 years

Ordnance Survey open data + QGIS, with a circular clip/fade in the print layout and you get some fancy, same-scale city footprint graphics, if you're into that kind of thing

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Alasdair Rae

@undertheraedar

1 year

From a long list of unfinished blog posts - my attempt to calculate the population of Great Britain by altitude (pub quizzers unite)

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Alasdair Rae

@undertheraedar

4 years

I've had quite a few queries about population density stuff I've done in the past - so this is a very short thread about that (and not beyond that because I am mindful of where my knowledge ends, I hope!)

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Alasdair Rae

@undertheraedar

1 month

I saw this Met Office 'UK climate districts map' online so naturally I decided to try and figure out the population of each area whilst eating my lunch and these are the incredibly interesting results

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Alasdair Rae

@undertheraedar

5 years

A little bit of map fun. Population of the world, one degree of latitude at a time:

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Alasdair Rae

@undertheraedar

5 years

Brexcuse me but I mapped that ward-level Brexit data, only a couple of years after it was made available. Some very interesting local patterns - more here:

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Alasdair Rae

@undertheraedar

4 years

If it wasn't for Spain's Meseta Central (or the title on the image, admittedly) it wouldn't be so easy to tell what this is - and this also goes some way to explaining those earlier European population density maps I posted.

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Alasdair Rae

@undertheraedar

4 years

🗞️After 4,320 days and 190,020 emails, I'm moving on from the University of Sheffield, so I've written a short blog post about what's next (tl;dr see the new web link in my twitter bio) - I shall continue to post stats, maps and other stuff here 🗞️

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Alasdair Rae

@undertheraedar

4 years

An updated constituency/deprivation chart for England for the 2019 general election - looks quite different to before. See following tweets for comparison with 2017 and 2001 #ge2019 #ge2019data

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Alasdair Rae

@undertheraedar

5 years

When I did the deprivation by constituency by party colour chart, I then wondered what other elections would look like, so here's the 2017 election vs 2001 election, for England

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Alasdair Rae

@undertheraedar

3 years

and, should you have a burning question like 'how can I make one of these?' or 'where do I get the data?' then see my blog for all the answers

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Alasdair Rae

@undertheraedar

5 years

My maps and stats for the English Indices of Deprivation 2019 are now online – all 317 local authorities here: (with links to @mhclg data and docs) – short thread with some highlights to follow

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Alasdair Rae

@undertheraedar

3 years

More 10km x 10km city squares, this time a simple blue-green-grey approach to displaying the urban fabric, including parks and water - Edinburgh is of course very parky so is a good example

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Alasdair Rae

@undertheraedar

5 years

With recent release of QGIS 3.8 you can now export image sequences from the 3D viewer and patch them together as animations (using an external tool - I used ffmpeg for this) Here's a little tour of Ben Nevis in Scotland - 'tourist path', Carn Mor Dearg arête, Allt a' Mhuillin

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Alasdair Rae

@undertheraedar

2 years

🚨Big new batch of local GIS open data resources 🚨 for Great Britain - based on OS and ONS open data - a shortish thread (data for all local authorities individually, as well as full Great Britain files, all in one place - see screenshot at link below)

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Alasdair Rae

@undertheraedar

4 years

Australia joins the gang too now, even though it's so big it almost broke my computer. Nice though that the 1km population data picks out some quite small, isolated settlements.

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Alasdair Rae

@undertheraedar

1 year

I'm working on my spelling of mortgage, probably due to the shock of seeing how many households own without a mortgage!

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Alasdair Rae

@undertheraedar

4 years

the view from the east over the Baltic Sea, with St. Petersburg in the borttom left and and a good chunk of Finland in the middle of the image. The UK and Ireland are in the distance here. I find this particular view very interesting.

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Alasdair Rae

@undertheraedar

3 years

Thanks to @cartocalypse 's very clever method I have now figured out how to create a very simple population density profile line in QGIS and it looks like this for a chunk of England using 1km data (and a little bit of Wales)

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Alasdair Rae

@undertheraedar

4 years

now where was I? Oh yes, here's a view that includes Cairo, Istanbul, Tbilisi, Baku, Tehran, Baghdad and lots of other interesting places.

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Alasdair Rae

@undertheraedar

1 year

A short Glasgow Subway thread, starting with a little animated map of the 10.5km / 6.5 mile route, which opened in December 1896

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Alasdair Rae

@undertheraedar

3 years

A little bit of weekend map therapy, with a relief map of Scotland - simple, darkened tones and a bit of snow on the hills

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Alasdair Rae

@undertheraedar

3 years

A very simple plot of those areas in England among the 1% MOST deprived (blue 🟦), and 1% LEAST deprived (orange 🟧), according to the 2019 English IMD. The population in blue areas is c. 540,000, orange areas very similar (2020 mid-year estimates) - 10%-10% map in next tweet

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Alasdair Rae

@undertheraedar

6 months

A #30DayMapChallenge world map for today's Oceania theme - kind of reversing a popular internet map meme - you may have to look closely

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Alasdair Rae

@undertheraedar

4 years

I'll post the rest of these later on, but for now here's a closer view of the Philippines (I may turn all these into a book, who knows)

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Alasdair Rae

@undertheraedar

1 year

The longest line, part 2 - an exhaustive search for the longest straight line route in the UK, without crossing any public roads (same location as before but a bit longer) - includes a note on methods

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Alasdair Rae

@undertheraedar

4 years

New York City is somewhat exceptional so here's a slightly ridiculous close up looking down the eastern seaboard (I'll stop this now but may continue - we'll see)

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Alasdair Rae

@undertheraedar

2 years

Short map thread on geography of jobs across Great Britain, by sector, at local authority level. Coloured areas show where at least 1 in 10 jobs are in a particular industry (data: BRES 2020, ONS) - top areas are labelled

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Alasdair Rae

@undertheraedar

11 months

110 QGIS videos and one bad shirt on the channel now, including: - how to get data from that web map - summing populations by area - change map opacity by population value - blend text with map in print layout - calculate area overlap % - glowing lines

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Alasdair Rae

@undertheraedar

4 years

the final batch of these population density maps (for now) focuses on India and its neighbours, from different perspectives - with the final one offering a closer look at Sri Lanka

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Alasdair Rae

@undertheraedar

2 years

Brand new intermediate QGIS course just launched on @udemy after 6 months of planning and filming! Wooooo - almost 100 videos Non-profits, charities etc message me for free access #QGIS

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Alasdair Rae

@undertheraedar

4 years

This is a map showing all land over 2,000ft in Scotland just because @VictimOfMaths asked for it and because we need to know 'what's the longest distance you can walk above 2,000ft in the UK?' and suchlike

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Alasdair Rae

@undertheraedar

3 years

Exciting day tomorrow as the lovely swisstopo people open up their terrain data "Permission is no longer required for the use of most digital products such as national maps, orthophotos or geological vector data." (this includes commercial use)

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Alasdair Rae

@undertheraedar

2 years

My new online intro-level QGIS course is now live on Udemy, for anyone who wants to get into mapping - or knows anyone that does - see short thread below with further details

Map Academy: get mapping quickly, with QGIS

Go from map zero to map hero with QGIS: 'heat maps', locator maps, election maps, density maps, analysis, design + more

www.udemy.com

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Alasdair Rae

@undertheraedar

3 years

Let's see how many different types of housing I can squeeze into one view

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Alasdair Rae

@undertheraedar

6 months

Migration data from the 2021 census (lines connect current home with home one year previous) - always shows up some interesting ones, but 100 points to anyone who instantly knows what the long distance lines are (I'll share the geodata later on)

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Alasdair Rae

@undertheraedar

1 year

@MarkThackstone okay, you are now Minister for Location in the new Government of Bangoria, well done

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Alasdair Rae

@undertheraedar

4 years

I've been experimenting with simple ways of displaying data recently, plus looking at historic data on Gaelic, so here's a simple map showing the % of people in each 1981 enumeration district who were Gaelic speakers - showing only the numbers, roughly coloured by value

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Alasdair Rae

@undertheraedar

1 year

the people have demanded a London and south east zoom, so the people will have it

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Alasdair Rae

@undertheraedar

2 years

A little look at high/low modal age across UK local authorities - some basic observations - cities and university towns - coastal - modal age of 73 very common! (idea after @resi_analyst idea of doing this for modal housing type last week)

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Alasdair Rae

@undertheraedar

4 years

Some #QGIS and other tutorials that I've put together, if anyone needs ready-made material: QGIS Atlas by field - 3D interactives in QGIS 3D rendering with #aerialod Kepler -

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Alasdair Rae

@undertheraedar

3 years

A little look at the areas in England and Wales where the median house price is at least 10 times the median annual salary

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Alasdair Rae

@undertheraedar

1 year

100 years of the road numbering system in the UK 🥳

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Alasdair Rae

@undertheraedar

7 years

21 years of local house prices in a single gif? Why not. Designed to be watched on loop; look closely at 2008 and beyond. #housing #dataviz

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Alasdair Rae

@undertheraedar

5 years

Comparing historic and contemporary development with maps has never been easier, thanks to @natlibscotmaps - you can view side-by-side or use the very cool swipe feature (this is OS 1888-1913 series vs modern satellite view)

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Alasdair Rae

@undertheraedar

7 years

I'm writing a longer blog on geogiffery but it won't be ready for a while so in the meantime here are the countries of the world in a geogif

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Alasdair Rae

@undertheraedar

4 years

Population chunks of South America - small contribution to #30DayMapChallenge from me - a bit of population data + Aerialod, with a bit of text

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Alasdair Rae

@undertheraedar

4 years

I ran off a few of these for New Zealand overnight, because 'maps without New Zealand' is not part of my modus operandi (a bit rough round the edges perhaps, but they look about right to me) cc @iain_white

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Alasdair Rae

@undertheraedar

6 years

Okay, one more geogif, just because it's Friday - this time population density across Europe, using 1km grid data #dataviz #geogif (source: )

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Alasdair Rae

@undertheraedar

8 months

More land area calculations today, golf courses of Greater London this time. Guess what % of Greater London is golf course? (source is latest OS Open Greenspace file, includes a few driving ranges)

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@undertheraedar

1 year

Map of the day: Leeds is 61% green belt - plus link to maps for every other local authority

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