Tuesday, January 26, 2021

How Well Do You Know Mercator?

The Mercator Map Projection has some very well known problems. Invented in 1569 by Flemish cartographer Gerardus Mercator the map is very useful for navigating - particularly at sea. A straight line on a Mercator projection map is a line of constant true bearing, which makes it very easy for navigators to plot straight-line courses. Unfortunately because the linear scale of a Mercator projection map gets bigger with latitude geographical areas get distorted as you move away from the equator. For example on a Mercator map Greenland and Africa appear to be the same size even though Africa is in fact much larger than Greenland.

You probably already knew that. In fact I'm guessing you are already an expert on the problems of creating two dimensional maps of a three dimensional world. Which is why you should excel at completing the BBC's Mind-Blowing Map Quiz. In this quiz you are asked to answer six different questions - some of them directly related to the distortions caused by the Mercator Projection. 

If you get less than 6 out of 6 in the BBC quiz then you need to study the Mercator Map Projection a little more ...

The Organization of Cartographers for Social Equality believe that the Mercator map projection "has fostered European Imperialist attitudes for centuries and created an ethnic bias against the third world". However they do admit that the Mercator projection is a useful tool for European sailors.

If you want a more balanced account of the Mercator projection then you you should read Tass's excellent introduction to the Flemish Cartographer Gerardus Mercator and his popular map projection. Mercator - It's a Flat, Flat World provides a wonderfully illustrated history of the Mercator projection and its creator, while also examining the benefits and problems of this popular cartographic representation of the world.

Tass's analysis of the Mercator projection includes an annotated guide to Gerardus Mercator's groundbreaking 1569 map, the 'New and More Complete Representation of The Terrestrial Globe Properly Adapted for Use in Navigation'. This guided tour introduces you to the map and provides a close-up examination of some of the map's features. The tour explains why the map is so useful as an aide to navigating at sea. It also explores the extent and limitations of geographical knowledge in the period when the map was made.

Alongside this detailed tour of Mercator's 1569 map 'Mercator - It's a Flat, Flat World' explores why it is so difficult to create an accurate flat two dimensional map of a three dimensional world. It explores the advantages and disadvantages of some of the other map popular projections and it illustrates how the different map projections each distort different areas of the world.

The Shadow on the Map


Since the first release of Google Maps sixteen years ago the user interface tools of interactive maps has changed very little. The '+' and '-' buttons used for zooming in and out on the map has pretty much been a constant feature. As has the use of a search box (so that users can quickly find a location on the map) and map layer buttons (so that users can switch between satellite and road map views). 

Over the years the designs of these navigation tools have adapted and changed a little but the basic UI has remained essentially the same. Another user interface feature which has changed very little in the short history of online digital maps is the design of the mouse pointer. It is therefore surely time to revolutionize the appearance of the humble mouse pointer - to change the boring small white arrow into something larger and more dynamic. 

Let me introduce you to Willy Maps' Shadow Arm.Shadow Arm is an interactive online map on which the traditionally arrow mouse pointer has been replaced with the shadowy outline of an arm, hand and pointy finger. The result is a map with far more visual impact. A map where much more emphasis is placed on the location being identified by the map user. The mouse pointer even changes to a flat hand when the user is panning the map so there can be no misunderstanding that a location is being pointed to while the map is being moved.

I'm guessing that Shadow Arm was released at least partly as a joke. However, as an ex-teacher, I can assure you that the Shadow Arm map could be a useful tool for the smart board during whole class teaching. 

Monday, January 25, 2021

Who is Against Vaccinations?

A survey conducted by Carnegie Mellon University’s Delphi Lab suggests that more than 25% of Americans would not get vaccinated. If 1 in 4 people refuse to be vaccinated then the USA will struggle to ever escape from Covid-19 lock-downs.

While the survey is extremely worrying it is also helpful as it can help the CDC target where they need more education campaigns. You can explore the results for yourself on an interactive map created from the data by MIT Technology Review. Do your neighbors want to get vaccinated? is a choropleth map which shows the percentage chance that a person in each county in the USA will want to get vaccinated. 

If you live in Arlington county, Virginia then there is a 92% chance that your neighbors will want to get vaccinated. However if you live in Terrebonne, Louisiana then there is only a 48% chance that a neighbor wants to get vaccinated.

BTW if you are in any way doubtful of the need to vaccinate yourself against Covid-19 then you might want to view the latest data on the Johns Hopkins' Covid-19 Dashboard. One year ago the dashboard showed that 17 people had died from Covid-19. Just 12 months later and the number of deaths from this deadly virus now stands at over 2 million.

175 Years of the Dufour Map

The Topographic Map of Switzerland, also known as the Dufour Map, is the oldest official map series of Switzerland based on accurate geometric measurements. In 1845 the Federal Topographic Bureau, led by Guillaume-Henri Dufour, began publishing a map of Switzerland divided into 25 sheets. The original map was published at a scale of 1: 100,000.

To celebrate the 175th anniversary of the Dufour Map the Swiss Federal Office for Topography has released an interactive version of the original Dufour Map.The interactive map allows you to explore in detail the wonderful topography of the Swiss Alps and lakes and closely examine the wonderful mapping of the Swiss Office for Topography. 

The interactive map includes a number of markers with links to stories about the origins and impact of the Topographic Map of Switzerland series (in Swiss) These links include: a personal account from a cartographer about the dangers of surveying in the mountains; an account of a death and broken leg while surveying the Säntis mountain; information on how tall mountain peaks were targeted for triangulation by creating high signal points out of felled fir trees; explanations about the expensive surveying equipment used to map the country, and an explanation of how the height of Switzerland's mountains were calculated.

Saturday, January 23, 2021

The Map with a Pearl Earring

Many museums and art galleries around the world now use interactive mapping interfaces to allow visitors to explore individual works of art online. Presenting paintings as zoomable images provides a unique perspective which gives the viewer the opportunity to study a work of art in impressively close detail.Using the navigating methods of panning and zooming (which users are familiar with from using Google Maps), art lovers can study a painting at their leisure.

The level of detail revealed by an interactive painting interface is only limited by the resolution of the image and the number of zoom levels provided by the interface. If the original painting has been photographed in megapixels then the interactive painting interface can allow the user to zoom in on the smallest strokes of the artist's brush.

The Girl With a Pearl Earring is one of Vermeer's most famous works. Last year The Mauritshuis art museum in the Netherlands asked Hirox Europe to photograph Vermeer's masterpiece at the level of 4.4-microns per pixel. Such a detailed image of the painting allows the museum to assess the surface condition of the painting, observe cracks in the paint, and help evaluate past restorations of the painting.

You can evaluate the painting for yourself on Hirox Europe's interactive map of The Girl With a Pearl Earring. This interactive map allows you to view the painting in unprecedented detail. Zoom in on the painting and you really can see individual the cracks in the paint. 

The image of the painting captured by Hirox Europe is about 10,118 megapixels. Ten areas of the painting were captured in even more detail using a Hirox 3D microscope. Using the Hirox interface you can explore these ten areas as a 3D map. Doing this reveals the topography of the painting so that you can actually see the height differences of the paint used on different areas of the portrait.

Friday, January 22, 2021

The Covid City Exodus

In the last few weeks I have read a number of reports estimating that the population of London has fallen by as much as 300,000 during the Covid epidemic. Part of this fall can be blamed on Brexit (many foreign-born workers have left the UK during the last year) however it is also widely believed that the rise of home working has encouraged many people to move out of the capital.

When people are not so tied to the office they may have become less keen to pay the higher costs associated with living in a city. During lock-down the social and cultural benefits of large cities have also largely disappeared and may have made the idea of rural living far more attractive. But is there any evidence for the anecdotal stories that many people are abandoning city living. One place to look for this evidence could be in the changing cost of rental properties in both urban and suburban locations.

There is certainly some evidence of this exodus from cities in Apartment List's National Rent Report. The report explores how rental prices rose and fell in American cities during 2020. The report shows that some of America's most expensive rental cities have seen a sharp drop in rents, while more affordable cities have seen a modest increase in rental prices. 

The National Rent Report interactive map illustrates the large drop in rents in cities such as New York, Los Angeles and Chicago. On the other hand a number of more traditionally affordable cities, such as Boise and Memphis have seen modest increases in rents over the duration of the Covid epidemic. 

AdvisorSmith has also been analyzing the trends in U.S. rents over the course of 2020. In Cities Where Rents Are Rising and Falling the Most the business insurance company lists and maps the ten cities where rents rose the most in 2020 and the ten cities where rents fell the most. 

San Francisco and Mountain View, California are both among the list of top 5 cities which have seen the largest fall in rents. Boston and New York are also in the top ten cities experiencing the largest rental decreases. AdvisorSmith note that these cities contain lots of professional and technical workers. Of whom many have taken to working from home during the epidemic.

It does appear from the rise and fall in city average rents that many people have taken the opportunity to move further from the office to somewhere with cheaper rents. It may not be as simple as saying that many people are moving out of cities because of Covid. Not all workers are able to work from home and not everybody can easily move homes. It will be interesting to note over the next few years whether working from home becomes more common and more widely accepted and whether this leads to a fall in the number of people living in our largest cities. 

Thursday, January 21, 2021

Global Shipping Traffic

VesselFinder is an interactive map which shows in real-time the live position of over 100,000 vessels around the world. The map uses AIS and satellite data to track and map the locations of boats and ships on both inland rivers and on the world's oceans & seas. 

On the maps different colored markers are used to show different types of marine vessels. Yellow markers show the locations of cargo ships, orange markers indicate tankers and purple markers show yachts. If you click on individual markers on the map you can often view detailed information about the selected vessel (purple yachts tend not to have any background information).

Looking at the VesselFinder map today you can clearly see there are a large number of yachts taking advantage of the trade-winds to make easterly crossings of the Atlantic (the line of purple vessels on the map above).


MarineTraffic is another popular interactive map which allows you to view the live position of ships around the world. The MarineTraffic live ship tracking map includes an option to view a density map of the world's shipping traffic. If you select the 'Density Maps' overlay on MarineTraffic you can view an overlay which shows the accumulated recorded data of all vessels on MarineTraffic over recent years. 

The density map (shown above) of global shipping reveals the world's major shipping lanes and also the areas of the world that the major shipping companies avoid. The reasons why some areas of the world's seas and oceans don't see as much traffic as others can vary from geo-political reasons to the dangers of piracy and local sailing conditions.

If you zoom in on the coastline of North Korea on MarineTraffic you can see that there don't seem to be many ships breaking the international trading sanctions. The coastline of Somalia is another area which often has less dense marine traffic than other coastlines. The reason that ships avoid Somalia is presumably to do with the dangers of piracy.

Bernie Sanders at the White House

Bernie sits outside the White House

A picture of Bernie Sanders sitting in a pair of mittens at President Joe Biden's inauguration quickly went viral yesterday. The picture shows Sanders sitting cross-legged and wrapped-up against the cold in the bleachers on Capitol Hill waiting for Biden to be sworn in.

While the fashionistas of social media focused on the stunning outfits worn by the likes of Lady Gaga and Michelle Obama some of us were more impressed by the casual attire modeled by Mr Sanders. Bernie's combination of an olive-colored winter jacket with brown and white knitted mittens was at once daring and inspired and ensured that the still glamorous elder statesman stole the show. 

Soon after Bernie's appearance at the inauguration a 'Bernie sits' meme suddenly started to flood social media. Pictures of Bernie sitting in his mittens were Photoshopped into different locations around the world. 

You can join in by creating your own memes with the Bernie Sits application. Just enter a location into Bernie Sits and the app will superimpose a picture of Bernie sitting in his woolly mittens on top of that location's Street View image from Google Maps.

Wednesday, January 20, 2021

The Interactive Map of World Fiction

I am really interested in some of the attempts people have made to organize works of fiction into two dimensional mapped spaces. In November's #30DayMapChallenge I even created a very small Island of Fiction map demo myself to explore how fictional authors could be mapped onto the fictional territories of a fictional island. 

Most interactive maps of books that I have seen have used the idea of genres as the guiding taxonomic principle, determining where individual works of literature are placed on the fictional map. My own Island of Fiction map mapped fictional authors onto five genre states, 'Crime', 'Horror', 'Science-Fiction', 'Romance' and 'Fantasy'.

TheLibraryMap also uses the idea of fictional genres as its organizing principle. TheLibraryMap is an interactive map of over 100,000 books which are organized based on 'the genre and topics of each book'. On the map individual books are colored by 'genre and topics'. Unfortunately TheLibraryMap doesn't have a map key so you will need to guess which color represents which genre of literature. Individual books on the map are also sized differently - but again without a map key we are left to guess what the size of each circle represents (total sales maybe?).

TheLibraryMap provides no information on how each book was placed into its genre. Usually with such a large taxonomic interactive map entities are mapped using machine learning. But I have no idea if that is the case here. It would be really interesting to know more about how the books were organized on TheLibraryMap. It might explain for example how existential novels by Camus and Sartre end up sitting so near on the map to fantasy novels such as 'Throne of Glass' and 'Red Queen'. 

The HathiTrust Digital Map is a very similar interactive map which allows you to browse and explore the 14 million volumes in the HaithTrust's repository of digitized texts. This map not only provides a visual interface with which you can navigate the books in the HaithiTrust digital library it also includes a fascinating discussion about how the texts are organized on the map. A discussion which explores how organizing digital texts may require a whole new system of library classification.

The Library of Congress Classification system categorizes books into different broad subjects and then by sub-classes within each of these subjects. The HathiTrust Digital Map uses an entirely different method of classification. On this interactive maps texts are organized by the similarity in the vocabulary of individual texts.

The 'Read' section of the HathiTrust Digital Map takes you on a story map tour of some of the interesting patterns that have emerged by organizing this Digital Library by vocabulary similarity. The story map shows you how this classification system diverges or resembles subject based classification systems, such as the Library of Congress Classification system. It also explores some of the new 'clusters' of books that emerge when you classify by vocabulary similarity. New clusters of texts which have some syntactical similarity but which under a subject based classification system would be classified far apart.

This story map tour also provides a great illustration of how a digital map of a library can actually use a number of different library classification systems at the same time. On the HathiTrust Digital Map the texts are organized spatially by their similarity in vocabulary. However as you progress through the story map the texts are also organized by language and then by subject matter by applying different colors to the markers of books in different categories. In this way the map is able to pick out interesting clusters of texts which have similar vocabularies within subject classes, texts which have widely different vocabularies but are still in the same subject class or texts which have similar vocabularies but are in different subject classes.

The Distribution of Surnames

The German Surname Map is a fascinating tool for visualizing the geographical distribution of surnames in Germany. Enter a surname into the tool and you can view a map showing where people with that name are distributed throughout the country. 

If you enter the name Merkel into the map (the name of the German Chancellor) you will discover that it is a common surname in Germany, with quite an even distribution throughout the country. Angela Merkle was born in Hamburg. There appear to be quite a few Merkles in Hamburg, although the biggest concentration of the surname appears to be in some of the southern states.

In Germany you can also use GeoGen to view the geographical distribution of German surnames. The use of three dimensional stacks on this map helps to make it a little more clear where a particular surname has its highest concentration in the country.

Searching Merkel on GeoGen and the German Surname Map seems to suggest that the highest concentration of Merkels in Germany can be found in Baden-Baden. However as neither map uses place-name labels it isn't always easy to determine individual towns on either map (the highest concentration of Merkels may therefore be in one of Baden-Baden's closest neighboring towns). 

If you want to research the geographical distribution of surnames in other countries then you can use:

You can also explore the global distribution of your family name using Forebears. You can use Forebears to undertake a global search for your surname. If you enter a surname into Forebears it will tell you the meaning of your name and show you a map of the global distribution of your name. Beneath this generated map you can view a list showing the number of incidences of your surname recorded in each country around the world. It also shows the ratio of people with your surname in each country and the rank of your name in comparison to the incidence of all over surnames in each country.