champagne anarchist | armchair activist


On average, a windchill (gevoelstemperatuur) of –15 occurs three times per year in the Netherlands. «One can weather that with extra scarfs and a warm hat.» And if people do freak out, there’s still weatherman Gerrit Hiemstra, who will argue for common sense and warm sweaters.

1. January 2010

Only die-hard homeless people still sleep outdoors. «Last year, a homeless person told our mobile team: ‘Get lost, it’s only minus eightteen’. But now most are indoors. At least they’re somewhat sensible. Especially with the wind freshening, the cold feels disagreeable.»

2. December 2010

It’s the coldest December in over fourty years.

According to satirical website De Speld, anti-swearing group Bond tegen het Vloeken objected against describing the cold with swearwords. The Bond tegen het Vloeken takes a different position. According to a spokesperson, it’s rather cold today.

3. February 2012

At 7 February in the morning, the windchill was exceptionally low. At many places, windchill dropped to –25 degrees at dawn.

Carnival fever has reached high levels, but the mercury stays behind. Building clubs [for carnival floats] are stuck with cans of frozen paint and are working at Siberian cold locations.

In Russia, they’re not impressed with the Dutch minus 15. Minus 36, that’s cold.

4. March 2013

In central Netherlands, March 2013 was the coldest since 1962; in England it was even the coldest March since 1883. The cold air was supplied by an exceptionally strong and persistent current from Siberia.

Weatherman Gerrit Hiemstra sees only one solution: ‘Let’s make this a warm sweater weekend’.


The fastest speaker of the Amsterdam City Council

I’ve downloaded the reports of 205 city council meetings (as well as 1,116 council committee meetings) from the website of the City of Amsterdam. They contain over 38 thousand text fragments spoken by council members. Each fragment comes with an indication how long the council member had the floor. From this, it should be possible to calculate how fast council members speak.

The chart below shows the correlation between speech duration and the number of words, for the current city council period (see Method for caveats):

There’s a strong correlation: longer speeches contain more words (rank correlation 0.95), which shouldn’t come as a surprise. The median rate is over 158 words per minute, but this varies per council member. The red dots represent Jan Paternotte, the fastest speaker of the city council (he has since become a member of the national parliament). During this council period, his median rate was over 185 words per minute.

This doesn’t mean he rushes through his text. Here is an example (starting at approximately 59 minutes) where Paternotte speaks at his characteristic rate. For comparison, the speech by Daniel van der Ree (starting at approximately 6:08) is close to the median rate for all council members.

It’s tricky to compare these outcomes with data from other sources, but with that caveat: Paternotte speaks faster than the average news reader at BBC radio, but slightly slower than radio news readers of the French RF or the Italian RAI (not to mention the Spanish RNE).

UPDATE - Valid criticism of the chart title here (in Dutch).

Method (and an update on open council data)

For this analysis, I used the ‘old’ source for city council information. When I had almost finished, a press release announced that council information is now available as open data. Amsterdam participates in the commendable Open Raadsinformatie programme, which aims to make the city council information of over one hundred Dutch municipalities available as open data, in a uniform format. This will make it easier for journalists, researchers, app developers and anyone else who is interested to access and use this data.

Council members in Amsterdam have for quite some time been asking for open city council information. Participation in Open Raadsinformatie was meant to provide for this. However, at this moment only council meeting reports and voting results are available, and only in pdf format. This means that Amsterdam trails cities like Utrecht in terms of transparency.

Open State, an organisation that plays a key role in the Open Raadsinformatie programme, indicated that service provider NotuBiz currently makes agendas and agenda items available as part of a pilot. They are currently evaluating the pilot with the national organisation of municipalities VNG and their customers, and considering adding more data and functionality in the future.

For now, I used the ‘old’ source. Its search functionality is sub-optimal, but in this case I could get around this by scraping the site map.

The amount of text in the reports varies considerably; as of 2015, more text is available than in previous years. Further, the speech rate is higher in more recent years: a median of 158 wpm for the current council period, compared to about 145 wpm before that. I’m not sure how this can be explained, but it appears that minute taking has improved over time. Before 2015, there are frequent examples of meetings for which (almost) no speech has been reported. All in all, it appears that the data for the current council period is the most reliable.

The chart omits a few outliers. Further, I excluded speech of the chairmen of meetings from the analysis; this contains more noise. This script shows how I collected and anlysed the data.

Embedding tweets in Leaflet popups

I just created a map showing where so-called Biro’s (small cars) are parked on the pavement and annoying people. Twitter has quite a few photos of the phenomenon. In some cases, finding their location took a bit of detective work.

First you’ll need the embed code for the tweet. You can get it manually from the Twitter website, but if you want to automate your workflow, use a url like the one below. It’ll download a bit of json containing the embed code:

When trying to embed the tweets in Leaflet popups, I ran into a few problems:

  • When popups open, the markers didn’t properly move down. As a result, most of the popup would be outside the screen. The problem and how to solve it are described here.
  • Twitter embed code contains a script tag to load a widget. Apparently you can’t execute javascript by adding it directly to the html for the popup content, but you can add it using a selector (cf here).

Here’s the code that’ll solve both problems:

map.on('popupopen', function(e) {
    var px = map.project(e.popup._latlng); 
    px.y -= e.popup._container.clientHeight;
    map.panTo(map.unproject(px),{animate: true});

You may also want to do something about the width of the popups, because otherwise they will obscure most of the map on mobile screens and it will be difficult to close a popup (which you can normally do by clicking outside of the popup). You can change the width of embedded tweets, but this will not change the width of the popup itself. A simple solution is to give popups a maxWidth of 215 (.bindPopup(html, {maxWidth: 215})).

Of course, you could also vary maxWidth depending on screen width, but I think 215px works well on all screens. Further, embedded tweets appear to have a minimum width of about 200px, so if you want popups narrower than 215px you’ll have to figure out a way to fix that.

If you embed tweets, Twitter can track people who visit your webpage. Add <meta name="twitter:dnt" content="on"> to your page and Twitter promises they won’t track your visitors. I wasn’t sure whether this should be put in the web page itself or in the html content of the popups (I opted for both).

If the popups have a somewhat spartan look and do not contain photos: Good for you! You’re probably using something like Firefox with tracking protection enabled. This blocks sites which have been identified as ‘engaging in cross-site tracking of users’ - including, apparently,

New Year - time to delete your Facebook account?

Around New Year, people turn to Google for advice on how to accomplish their New Year’s resolutions. The chart below (an update of one I created earlier) illustrates this.

Around New Year, there’s is a peak in people googling ‘quit smoking’, but it appears that even more people to try to figure out how to delete their Facebook account. The parallel is not entirely surprising, given claims that platforms like Facebook are designed to be addictive.

Chart updated 1 January 2018


Амстердам, mapped by the Soviet Union

For fifty years, the Soviet Union had an ambitious military programme to map large parts of the world. Two collectors, John Davies and Alexander Kent, have written a great book about the secret maps that resulted from this programme.

Most of the maps in their book are of the US and the UK. Their descriptions are so intriguing that I had to find out whether Amsterdam has also been mapped. It turns out it has: on Ebay, I found a reproduction offered for sale by the Jana Seta Map Shop in Riga.

The map consists of four sheets, each more than a metre wide and 90cm high. The left margin of the fourth sheet contains the following text:

If I’m not mistaken, this text contains the following information: the scale of the map; the name of the city; the reference numbers of the 1:100,000 maps with the location of the city; the sheet number (4/4); the status of the map (SECRET) and the year of publication.

So it appears that the map was published in 1985, but that’s not the whole story. At the bottom of sheet 4, the following text is printed:

Sometimes, this text would contain the names of the people who had created the map (frequently women), but that’s not the case here. I think it says here that the map was compiled in 1972 and updated with material from 1980. By the way, a description of Amsterdam printed next to the map also refers to demographic information from 1981.

To check how recent the material is, I created a map of Amsterdam with buildings from 1980 and 1981 colour-coded. This shows that in those years, most construction took place to the south-east of the city, beyond the Bijlmer neighbourhood. The fragment below shows the area between the Academic Medical Centre and the Gaasperplas (click on the image to open it in a new screen).

For comparison, here’s roughly the same area from the Soviet map.

Generally, buildings from 1980 (orange) and before are shown on the Soviet map, while buildings from 1981 (red) are not. This seems to confirm that the map was updated with material from 1980.

The cartographers who created the maps used satellite images, local maps and other public sources, and sometimes information collected on the ground.

Some maps show new buildings but without the corresponding street names. The explanation may be that cartographers had access to recent satellite images showing the buildings, but no local maps were available yet from which the street names could be taken, Davies and Kent explain.

Something similar may apply to the Bijlmerbajes, a former prison which now houses a refugee centre.

The Bijlmerbajes opened in 1978. The map shows the prison buildings: they are east of the tracks, with a ditch in between. However, there’s no explanatory text: the only text is the name of metro station Spaklerweg. It appears that the cartographers did have access to recent satellite images showing the buildings, but no information about their function.

I don’t know whether any Dutch maps which identify the Bijlmerbajes existed in 1980. The Dutch Land Registry has a handy website with historical maps. It contains a map from 1981 identifying the Bijlmerbajes as gevangenis (prison).

The prettiest parts of the map are the harbours, that have been mapped in great detail. That’s not the case for Schiphol Airport, shown below.

The maps used a uniform colour coding. Simply put, green represented objects of military or strategic interest; purple, public institutions and black, manufacturing. Schiphol-Centrum (to the left) and Schiphol-Oost, with an aircraft repair shop (top right) have been marked as objects of strategic interest. Black blocks refer to the now closed Fokker factory, where military aircraft were produced

It’s striking how ‘empty’ Schiphol is. To some extent this is understandable: asphalt and wasteland make up a large part of any airport. However, it also appears that the cartographers didn’t have all that much information about Schiphol. For example, there used to be a depot for jet fuel (which was still delivered in barges) at Schiphol-Oost. If the cartographers had been aware of this, they would probably have included that information in the map.

Moving on to the harbours, here’s a part of the Western Harbour Area.

The Western Harbour Area contains one of the largest petrol harbours of the world. The green objects suggest the cartographers were rather interested in fuel infrastructure.

And here’s part of the Eastern Harbour Area.

There’s a lot to see here. The green triangle with number 29 represents the naval complex at Kattenburg (it has recently been abandoned by the Navy and will be converted into offices and housing). Interestingly, the square at the bottom of the triangle has also been marked as object of strategic interest. In the past this used to be a Navy warehouse, but it was turned into a Maritime Museum in 1973.

Other green objects include the Oranje-Nassau barracks at the Sarphatistraat (number 30, still in use by the army at the time) and the former location of the Nautical College (number 301).

There’s also a little green block between the Waterlooplein and the Nieuwe Amstelstraat (number 5 to the left of the photo). According to the map index, this is an арсенал or arsenal. In a way, that’s correct: the buildings name is Arsenal. The name refers to the fact that the building has been used to store arms in the past, but since 1946 it houses the Academy of Architecture.

Lovers of detail may want to zoom in to the Czaar Peterstraat. Soviet army maps used to write names phonetically, following the local pronunciation. The fact that this streets name has a Russian origin doesn’t change that: the tsar’s name is spelled Peter (Петер), not Pyotr (Пётр).

And here’s yet another strategic location, near the Museumplein.

Objects in this fragment include the American Consulate (number 166, but in a different building than where you’d expect it to be) and a bus stop where KLM busses to Schiphol Airport used to depart (number 187).

Of interest is number 250, located next to the Zuiderbad indoor swimming pool. The object is green, therefore deemed of strategic interest. The description says Служба безопасности or security service, according to Google Translate. That’s intriguing. Could it be that the map reveals an unknown location of the national security service BVD?

Not quite. This used to be the address of a precursor of the Dutch NIA (now part of TNO), an institute that dealt with workplace health and safety. Its former name was Veiligheidsinstituut or Safety Institute. However, the Dutch word veiligheid can mean both safety and security, which explains how the Soviet cartographers could have mistaken the Veiligheidsinstituut for a security service.

Details about Amsterdam

The Soviet city plans come with a general description of the city. To give an idea of the contents, here are some elements from the description of Amsterdam:

  • Because of dikes, rivers and canals and because of the viscous soil, movement of vehicles outside of the roads is almost impossible.
  • The destruction of hydraulic structures can cause catastrophic flooding of the terrain.
  • Along the roadside there are bicycle paths with a width of up to 2m.
  • All nearby settlements are electrified, provided with telephone communication, and have running water and gas.
  • From the air, Amsterdam is easily recognisable by its large size and its location between the IJsselmeer and the North Sea.
  • On some canals, there are many floating houses.
  • The metro lines have a length of 18 km (3.5 of which are underground) and number 20 stations, including 5 underground ones; the distance between underground stations is 0.8 - 0.9 km, between ground stations - 1.1–1.3 km

In addition, the text contains detailed information about manufacturing, research, administration and other topics.


I once started to learn Russian, but I never progressed much beyond я не говорю по-русски. To decipher Russian texts on the map, I used the Cyrillic keyboard of my iPhone for typing short pieces of text, and I scanned longer ones with the FineScanner app, which offers OCR for Cyrillic (this works as long as the text has a white background, but not with texts printed on the map itself). I used Google Translate to translate the texts. The result may not be perfect, but it appears to work pretty well.

I created the map with construction dates using Qgis and Open Street Maps map data, which contains data from the Land Registry (Kadaster).

I can’t rule out that my interpretation of the map (and the Russian texts on it) contains errors. If you have any comments, please let me know.

John Davies en Alexander J Kent, The Red Atlas: How the Soviet Union Secretly Mapped the World. University of Chicago Press, 2017.

Maps of other Dutch cities and detailed information here.