Saturday, February 27, 2021

Making History with Maps

Making History Sandbox is an interesting interactive mapping tool which allows you to make maps which show developments over time. It is probably easiest to explain this tool using a working example - so here is a little demo map of an animated timeline I created with Making History Sandbox.

Essentially the tool consists of a timeline and regions which can be colored on the map. To create a history timeline map you add frames to this timeline with different areas colored on the map. By adding additional frames to this timeline you are then able to show geographical developments over time. 

By default the world is mapped to the state level. However Making History Sandbox allows you to import your own region/territory data as a geoJSON file. So, for example, in the United States you could import county boundaries to plot developments over time at a higher resolution than the state level.

It is possible to save and load your created timelines. Unfortunately Making History Sandbox doesn't have a 'share' option so it isn't easy to share your created timeline with anybody else.

Friday, February 26, 2021

The Affordable Housing Map

The average house price for all home types in the United States is now around $295,000. The days of being able to buy a five figure starter home are fast coming to an end. But they aren't over just yet.If you want to know where your can find a home for less than $100,000 then you can refer to Social Explorer's Housing Units Less Than $100,000 interactive map.

Housing Units Less Than $100,000 uses data from the 2015-19 American Community Survey to visualize the density of affordable starter homes in the United States. This choropleth map shows the number of homes valued under $100,000 at the census tract level.If you click on an individual census tract on the map you can view the exact percentage of homes in the tract valued under £100,000.

The map reveals that the lowest density of affordable starter homes are along the east and west coasts. Texas appears to have the highest percentage of homes valued under $100,000. Seven of the ten counties with the highest percentage of five-figure homes are at the edge of the South Plains in Texas. These include King County, where 96.2% of homes are valued under $100,000, Stonewall County (90.2%), and Hardeman County (86.6%).

The Coronavirus Monitor

The map I have consulted most often in the last few months has been the Berliner Morgenpost's Coronavirus Monitor. The German newspaper's visualization of the epidemic not only provides a global overview of the present number of new infections in countries around the world but also allows you to explore how the virus has spread in those countries since the beginning of the outbreak at the start of last year.

Circles are used on the map to show the total number of cases of Coronavirus in each country (the red circles), the number of people who have recovered from an infection (green circles) and the total number of deaths (black circles). The larger the colored circle then the larger the number of cases. If you select a circle on the map you can also view the rates of cases, recoveries and deaths per 100,000 inhabitants. A timeline running along the bottom of the map allows you to view the data for any date since Jan 29 2020.  

Beneath the global Coronavirus monitor is another interactive map which shows the number of new infections over the last 7 days in each German state. You can also find graphs on the R rate in Germany over time, a bar chart of the number of weekly deaths, and data on the number of Germans who have been vaccinated against Coronavirus.

Thursday, February 25, 2021

The Stars & Warming Stripes

In 2018 Ed Hawkins, a climate scientist at the National Centre for Atmospheric Science at the University of Reading, released a powerful data visualization to illustrate how temperatures have risen around the globe over the last century. His visualization used colored stripes to show the average annual temperatures for every year of the last century. This type of data graphic is now commonly known as a 'climate stripes' visualization.

You can view the climate stripes of every U.S. state using the Stars & Warming Stripes visualization. Select a state from the drop-down menu and you can see the climate warming stripes which show how average yearly temperatures in the state have changed over the last 115 years. The visualization includes an option to view a scatter plot superimposed on top of the state's climate warming stripes.

You can also create warming stripes for each state and for other regions and countries around the world from Ed Hawkins' own #ShowYourStripes website. Select a region and then a country from the drop-down menu on #ShowYourStripes and you can view and download an image showing how temperatures have risen over the last 100+ years at your selected location.

Global warming stripes are a very powerful way to visualize a complex issue with one simple and easy to understand image. The general progress from blue to redder stripes is both visually striking and very hard to dispute. The temperature data used for creating the stripes on both Stars & Warming Stripes and from #ShowYourStripes come from the Berkeley Earth temperature dataset and from a number of national meteorological agencies.

100,000,000 OpenStreetMap Edits

Update: The 100,000,000th edit has now been made to OpenStreetMap. The edit was made by user Lamine Ndiaye, who made a change to OSM in Nianiane, in the Fatick Region of Senegal. Lamine has been a registered user of OpenStreetMap since 2013 and has made 2,151 edits to the map.

Later today the 100,000,000th edit will be made to OpenStreetMap. OpenStreetMap is a free crowdsourced map of the world which is edited and maintained by millions of volunteers all around the globe. Since its inception in 2004 over two million registered users have added millions and millions of new data and changes to this free map of the world. 

You can watch the 100,000,000 edit being made to OpenStreetMap live on the OSM in Realtime interactive map. This map displays in real-time the changes being made to OpenStreetMap around the world. At the time of writing the OSM in Realtime counter shows there have been 99,958,361 changesets made to OSM. When users edit OSM they can add new features to the map or edit existing data. When these edits are made the user writes a short message describing the change and then this message & the edit are saved as a 'changeset'. As you can see from OSM in Realtime the number of changes made to the world's leading crowdsourced map are fast closing in on 100,000,000.

You can also watch live changes being made to OpenStreetMap on ShowMeTheWay. ShowMeTheWay is an interactive map which highlights edits being made to OSM in real-time on top of satellite imagery. The map shows you the nodes, ways and relations actually being edited and provides information on those changes.

You can also view information about individual edits made to OSM on OpenStreetMap Changesets. This map allows you to view details about each individual edit made to OSM, including the name of the user, when the edit was made, and what data was added or edited on the map. After the 100,000,000 edit has been made to OpenStreetMap you will be able to explore details on the changes made at:

Wednesday, February 24, 2021

Street Fashion on Street View

European fashion retailer Zalando has launched a new and unique online shopping experience. With its new Street It All campaign Zalando allows customers to view and buy street fashions directly from a Google Map.

Using the Street It All interactive Google Map you can explore custom street views shot in four different Spanish cities. Click on the map markers in Barcelona, Madrid, Malaga and Valencia and you can view custom shot 360 degree panoramic images captured by Zalando. In these custom Street View scenes you will find models wearing Zalando's street fashions. 

If you like any of the clothes being modeled in these street scenes you can click on the featured item and buy the item directly from the map.


Of course when I say this is a 'unique' online shopping experience I am stretching the truth a little. Very little online is truly original and Zalando's Street View campaign is very similar to a campaign launched two years ago by Fred Perry and Raf Simons.

In 2019 Fred Perry and Raf Simons released their own virtual reality shopping experience. Fred Perry x Raf Simons is a custom Street View tour which you can navigate around just like you can move around in Google Maps Street View. However, unlike on Google Maps, on these virtual panoramas you can click on the people and buy their clothes.

All the models that appear in Fred Perry x Raf Simons are interactive. Click on a model and you can browse the clothes that they are wearing and even click through to buy an item on the Fred Perry online store. As on Google Maps all the models have their faces blurred. Some of the items of clothing are also blurred. This means that the item is not yet available to be purchased on the online store.

Mapping Attacks on the Press

Every year the Committee to Protect Journalists (CPJ) releases an annual report on the number of journalists imprisoned and killed by countries across the world. This year the CPJ has created a story map Attacks on the Press 2020 which explores in detail attacks on the press around the globe. 

In its annual global survey the CPJ report that across the world at least 274 journalists are in jail as a direct result of their work. This exceeds the previous high of 2016 when 272 journalists were imprisoned. Last year China was the worst country in which to work as a journalist for the second year in a row. In 2020 China imprisoned a number of journalists in response to how they reported on the outbreak and spread of Covid-19 and how their government were responding to the epidemic.

The CPJ map colors the world's countries based on the number of journalists that were imprisoned during 2020. The yellow dots show where journalists were killed in 2020 in relation to their work. As you scroll through the story the map pans to explain the attacks on the press in the worst offending countries. A menu allows you to switch between imprisoned journalists, journalists killed in 2020 and an 'explore' option. If you select 'explore' you can then click on the individual yellow dots on the map to learn more about the individual journalists who were killed around the world during the course of last year.

Tuesday, February 23, 2021

A Dot Map of Half a Million Covid Deaths

Almost half a million people have now died from Covid-19 in the United States. Yesterday, in Visualizing Half a Million Deaths, I looked at how data journalists at the New York Times and the Washington Post have attempted to visualize the scale of the tragedy experienced over the last year. 

Both the NYT and the Post have created data visualizations which attempt to portray the scale of half a million deaths to their readers. In 500,000 Lives Lost NBC News has taken a different approach, using an interactive map to visualize where those 500,000 victims of Covid lived. The map plots half a million red dots, each dot representing one death from the coronavirus. 

The map includes a scollytelling element which provides a chronological view of the spread of Covid-19 across the United States over the last year - beginning with the first reported U.S. death in Washington state on Feb. 29th 2020 (although it was later revealed that the first Covid-19 death occurred a few weeks earlier in Santa Clara, California). As you scroll through the story the map moves to different locations to explore where significant outbreaks have happened during the course of the pandemic.

If you scroll to the end of NBC's story you can actually explore the map for yourself. Enter an address or zip-code and you can view the number of deaths at your chosen location via the density of red dots on the map. The dots don't reveal the actual addresses of individual victims of Covid-19. The location of the dots are randomized within each census block area.

The Dot Map of the 2020 US Election

After both the 2012 and 2016 U.S. Presidential elections Kenneth Field of Esri made impressive dot maps showing where people had voted for the Democratic and Republican candidates. Kenneth has now completed and released his dot map of the US Presidential Election 2020.

The US Presidential Election 2020 interactive shows around 160 million dots (158,383,403), or one dot for every person who voted in the election. On the map blue dots were used to show Democratic votes and red dots to show Republican voters. If you click on the map you can read a more detailed breakdown of the number of Democrat and Republican voters in the selected county and which candidate won the county and by what margin.

The dots don't show the actual locations of voters in each county but are randomized within populated areas. Kenneth's map is a dasymetric dot map. This means that that the county level election data has been distributed as individual colored dots within the county in the areas where people actually live.This leaves areas where people don't live empty (because there are no voters there). The result is a dot map which reflects more truly how many people live in the rural and urban areas of each county.

You can learn more about how Kenneth made the map on a two part blog post on the Esri website, Experiments with Dot Density - Part One and Experiments with Dot Density - Part Two. And, if you are interested, you can view Kenneth's U.S. Presidential Election 2016 dot map here.

Monday, February 22, 2021

Raphael's Cartoons

One of the many wonders of London's fantastic free museums is the Raphael Court in the Victoria and Albert Museum. This large gallery hosts the enormous Raphael Cartoons, which were created by the Renaissance artist in the 16th Century.

In 1515 Pope Leo X commissioned seven huge tapestries which he wanted to hang in the Vatican’s Sistine Chapel. Michelangelo had completed his ceiling in the Sistine Chapel just two years before the tapestries were commissioned. Raphael was very conscious that his tapestries would be shown beneath this magnificent ceiling, he therefore took great care in perfecting the designs in the cartoons, from which the tapestries would be made.

These seven cartoons, the full-scale designs for the Vatican tapestries, can be viewed in the V&A. At the time of writing the V&A is closed because of the pandemic. However you can now examine Raphael's Cartoons online using the museum's new Explore the Raphael Cartoons interactive site. The V&A's site allows you to examine each cartoon as you would an interactive map, allowing you to zoom in on details in the cartoons. The cartoons depict biblical scenes from the lives of Saints Peter and Paul. Each cartoon on the V&A site includes interactive markers which you can click on to learn more about the scene depicted.

The actual tapestries, created from Raphael's cartoons, are still hung in the Vatican on special occasions. Unfortunately the Vatican's Sistine Chapel Virtual Tour doesn't show the chapel with the tapestries in situ. However the virtual tour does allow you to see where the tapestries are hung (where the plain tapestries are hanging in the panoramic tour). This allows you to get some sense of the scale of Raphael's cartoons (which is not very obvious from viewing the V&A's interactive versions of the cartoons).

The interactive image of each of cartoons on the V&A website has been visualized using the OpenSeaDragon viewer for high-resolution images.


If you want to explore more of the world's best museums and galleries during lock-down then here are a few more virtual tours that you might enjoy:

The Uffizi Galleries Virtual Tour - one of the greatest collections of Renaissance art in the world
The Metropolitan Museum of Art - includes a number of virtual exhibitions
The National Gallery - London's National Gallery has a number of virtual tours
The Rijksmuseum Masterpieces Up Close - a virtual tour of the museum's Gallery of Honour
The Smithsonian National Museum of Natural Museum - has created a number of virtual tours
The Stonehenge Virtual Tour - places you in the center of this mysterious pre-historic monument
Beijing Palace Museum - the Palace Museum has created a number of virtual tours which allow you to explore some of the museum's galleries and also some of the amazing buildings of the Forbidden City
Buckingham Palace - take a virtual tour around the Queen's favorite pad
Van Eyck Virtual Tour - the Ghent Museum of Fine Arts' impressive Van Eyck virtual exhibition

Visualizing Half a Million Dead

The Johns Hopkins Covid-19 Dashboard is currently reporting that there have been 498,897 deaths from the coronavirus in the United States. As the USA approaches the terrible milestone of half a million deaths from Covid-19 data journalists have been given the morbid task of thinking about how best to visualize the dreadful impact that the pandemic has had on American lives.

One common response to the problem of visualizing the scale of half a million people is to turn to familiar geographical comparisons. For example the Washington Post in 500,000 dead, a number almost too large to grasp explains that it would require 9,804 buses to carry 500,000 people. It then shows how long a caravan of 9,804 buses would stretch by mapping the distances between different cities (for example 9,804 buses would stretch from Philadelphia to New York).

This isn't the first time that the Washington Post has relied on its readers' geographical knowledge in order to try to visualize the scale of Covid-19 deaths in the United States. In September the newspaper created an interactive map which allowed Americans to visualize what 200,000 deaths would look like if they occurred in their town. 

In What if all covid‑19 deaths in the United States had happened in your neighborhood? the Post showed the scale of 200,000 people in relation to readers' local populations. Enter an address into the WaPo's interactive map and it will draw a circle around your home showing the extent where 201,688 people live.

In less than five months the number of deaths from Covid-19 has more than doubled (from 200,000 in September to half a million in February). Yesterday's New York Times front page carried a simple graphic which effectively visualized the timeline of those half a million deaths since the start of the pandemic. 

The Times' graphic shows 500,000 dots (one for every death). The points are plotted chronologically from the top of the page to the bottom. The first dot at the top of the page represents the first death from Covid-19 in the United States on 29th Feb last year. The density of the dots at the bottom of this timeline provide a clear picture of how the death rate from Covid-19 has accelerated since the beginning of January of this year.

A version of yesterday's Times front page was originally posted online in late January. You can see this graphic in the story How 450,000 Coronavirus Deaths Added Up

The death rate from Covid-19 is now falling in the U.S. and with more and more people being vaccinated the end of this crisis may now be in sight. However the Times' graphic clearly shows that it isn't over yet and there remains a clear need to stay vigilant against the dangers of catching Covid-19.

Saturday, February 20, 2021

The Noisy Children Map

The Dorozoku interactive map has stirred up a lot of noise in Japan. The Dorozoku (road-tribe) map is a crowd-sourced noise pollution map which anyone can use to identify noisy streets. People are using the map to complain about noisy children playing on the street or about adults standing around and talking loudly.

One typical complaint on the map reads.

"It's noisy and dangerous as many children in the neighborhood gather and run around."

Not everyone is happy with the map and some see it as encouraging intolerance towards children. Thousands of users of the map however have been keen to take to the map to identify streets which they think are too noisy or where playing children are causing damage to property. In fact it appears that people like to complain about their noisy neighbors and the Dorozoku map features a lot of noisy roads. 

The road-tribe map isn't solely concerned about noise. The map is designed so that people can report where roads are being 'misused' for such things as barbecues and games of football. The map's creator believes that such 'misuse' of roads can be both noisy and dangerous.

Friday, February 19, 2021

The Mars Rover Tracking Map

Yesterday NASA's Perseverance rover landed successfully on Mars. NASA's 2020 Mars mission is to examine the geology of Mars looking for the biosignatures of past microbial life on the red planet. In order to carry out this mission the Perseverance rover is also equipped with the Ingenuity helicopter drone. The Ingenuity drone will be used to help scout for points of interest which the Perseverance rover will then investigate and study.

You can follow the progress of the Perseverance rover on Mars using NASA's Perseverance's Location interactive map. The map shows Perseverance's current location, showing where the rover landed yesterday in the Jazero Crater, about 8km from the crater's western boundary. Excitingly the map includes a button to turn on or off the rover's path, which suggests that the map will be used to show Perseverance's near real-time movements on Mars.

Also to the west of Perseverance's current location is the Neretva Vallis. This former river valley is where water once entered the Jazero Crater. About 40km east of Perseverance's landing site the Pliva Vallis is where that water flowed out of the crater. It is therefore believed that the Jazero Crater was once an open basin lake, a freshwater lake which could have been conducive to life.

You can learn more about the Jazero Crater and even explore its terrain for yourself on the amazing Jazero Explorer. The Jazero Explorer is a 3D map of the crater and its immediate surroundings. It is also an amazing story map which provides a fascinating introduction to the Perseverance landing site on Mars.

As you progress through the Jezero Explorer you are taken on a tour of the Perseverance landing site and the Jezero Crater. During this guided tour you can learn more about why the crater was chosen as the focus of the 2020 Mars mission. This tour includes information about the crater's geology, terrain, sediments, channels and river systems. One reason why Jazero was chosen for this mission is because the crater has been identified as one of the most promising environments to discover the biosignatures of past microbial life on Mars.

Thursday, February 18, 2021

Every Map Projection at Once

Overlapping Projections is an interesting map which shows 70 different map projections all at once. The result is a map of the world which is still recognizable but very blurry at the edges. 

Overlapping Projections is a simple but effective visualization of how different map projections distort the size of countries around the world. Over the years there have been quite a number of clever interactive demonstrations of how different map projections represent the geography of the world. 

Here are a few of my favorite map projection visualizations:

If you are interested in how different map projections distort the world then you will probably like Projection Face. Projection Face is a great illustration of the distortions created by different map projections. The interactive shows how 64 different map projections effect our view of the world by showing each projection's effect when applied to something very familiar - the human face.

The distortions of each of the different projections can be illustrated further by clicking and dragging any of the mapped faces. This illustrates how the different map projections can be distorted themselves simply by changing the center of the map.

Projections Face is an interactive version of a 1924 illustration from Elements of Map Projection with Applications to Map and Chart Construction.

Comparing Map Projections is a clever visualization of different map projections. It allows you to directly compare different types of map projections and see the levels of distortions which each map projection introduces by visualizing a globe in two dimensions.

This interactive visualization provides a useful overview of the advantages and the disadvantages of specific map projections. For example if you select the much maligned Mercator map projection you can see that it scores very low for angular distortion. This means that all the lines of longitude are straight (compare the vertical lines of longitude on the Mercator projection to those on the Sinusoidal projection). The result is that a Mercator projection is really useful for navigation.

However when you explore the Mercator projection on the Comparing Map Projections interactive visualization you will also see that it has very large overall scale and angular distortion. A consequence of having a very low angular distortion is that the Mercator projection distorts scale (especially the further you move from the equator).

As you can see from Comparing Map Projections all map projections introduce some degree of distortion. 


If you want a little help deciding which map projection you should use for your current map project then you can use the Projection Wizard to decide on the best projection.

This map projection guide allows you to select the extent of the map view you are working with by outlining the area on a Leaflet map. Once you've highlighted your map bounds you can choose a distortion property (Equal-area, Conformal, Equidistant or Compromise).

The Projection Wizard will then suggest which map projection you should use depending on the extent and the distortion property of the map. The suggested projections are based on 'A Guide to Selecting Map Projections' by the Cartography and Geovisualization Group at Oregon State University.

A Proj.4 link is provided next to each suggested projection, which opens a popup window with a Proj.4 library. Once you've settled on your map projection you might want to check-out the Proj4Leaflet plugin for using projections supported by Proj4js with Leaflet powered maps. 

Worldwide Cell Tower Distribution

The Cell Tower Distribution map reveals where cell towers are distributed around the globe. The map uses OpenCelliD, the world's largest open database of cell towers, to visualize the density of cell towers across the world. 

If you are afraid of your phone losing its connection then I would advise traveling in the Sahara, the Australian outback, in the Amazon, in Siberia, Greenland or the North of Canada. All these regions of the world appear to have very few cell towers. It is almost as if there is no demand for phone coverage in these areas..

You can compare the global cell tower distribution map with the actual global population using Duncan Smith's World Population Density interactive map. This map uses data from the Global Human Settlement Layer (GHSL) (by the European Commission JRC and CIESIN Columbia University) to visualize where people are living around the world. It turns out that there are actually very few people living in the Sahara, the Australian outback, in the Amazon, in Siberia, Greenland or the North of Canada.

The Cell Distribution Map doesn't show the locations of individual cell towers. However if you zoom-in on the OpenCelliD interactive map then you can actually see where individual cell towers are located. On this map you can even click on individual cell towers to discover a tower's radio type and range. Zooming out on the OpenCelliD map also reveals the global distribution of cell towers.

Wednesday, February 17, 2021

The Distance to Your Nearest MiLB Team

This season there are 120 Minor League Baseball (MiLB) teams. That is 43 less teams than last year. One consequence of this reduction in the number of teams is that a lot of baseball fans will now have to travel a lot further to attend a Minor League Baseball game.

In Where it's harder to watch a Minor League Baseball game in 2021 Axios has mapped out the distance from every county in America to the nearest Minor League Baseball team.The map shows the location of all 120 Minor League Baseball teams and also the locations of the 43 teams which have been removed from the league since last season. The map also includes a visualization of the distance from each county to the nearest MiLB team.

The biggest losers this season are baseball fans in Montana. Not only did Montana lose three Minor League Baseball teams this season but the state is now also one of the furthest states from any remaining MiLB team. If you live in Montana then you will need to travel at least 260 miles to visit your nearest MiLB game. Things aren't much better for fans in the other Mountain States of Wyoming, Colorado, and Idaho. Fans living in these states also face very long journeys if they wish to attend a MiLB game.

All of this talk of traveling to games could be academic. Last season's MiLB season was canceled as a result of the Covid-19 pandemic. If this year's season does go ahead it is likely to be delayed and if fans are able to attend games then it is more than likely that the number of fans allowed at each game will be severely restricted.

Clouds are Gathering Over Mapbox

Update: William B. Davis has now released a working demo map and blog post about his original Cloud Effect Using Turf.js and Mapbox.GL. The post includes an interactive map with animated cloud and an explanation of how the effect is created, using Mapbox's circle-blur and circle-opacity (and turf.js for the animation).


Darren Wiens has created a fun map which demonstrates how clouds (or smoke) can be animated on top of a Mapbox map. His Particle Playground map shows moving banks of cloud forming over Vancouver Island and drifting out over the Pacific. 

The map includes a number of controls which allow you to adjust the color of the moving cloud and the size, density and lifespan of the cloud particles. Looking beneath the hood of the map the animated cloud particles appear to be loaded on to a canvas layer on the map and then animated using turf.js. 

Although Particle Playground is fun to play with it could also be a useful visual effect to add to an interactive map. For example an animated cloud layer could be useful for a weather forecast map which wants to show the predicted cloud cover over a period of time at a specific location. 

Darren Weins was inspired to create his working demo of Particle Playground by a series of Tweets by William Davis of Mapbox in which he posted a series of GIFs of animated clouds moving on a Mapbox interactive map. One of these GIFs visualized smoke emanating from a wildfire polygon, demonstrating how animated smoke particles could be used by a wildfire map to show a forecast of the density and direction of the smoke caused by a wildfire.

Tuesday, February 16, 2021

A Quiet Chinese New Year

Last Friday (12th Feb) was Chinese New Year. In a normal year around 2.8 million trips would have been made by Chinese people traveling to visit and stay with relatives over the Spring Festival holiday. During this year's Spring Festival, because of the Covid-19 pandemic, travel in China was down by at least 50% on last year.

Thanks to Baidu maps we are able to see when, where and how Chinese people travel during the Spring Festival. Baidu's mobile map application has over 350 million active users and receives over 10 billion location requests every day. This provides Baidu with a unique insight into the movements of the Chinese population over the Spring Festival.

Every year Baidu releases its Qianxi (migration) visualization. This interactive map allows you to explore which national highways were the most congested over the Chinese New Year Spring Festival. It also allows you to visualize the movements to and from China's largest cities over the holiday period. This year the number of people making city to city journeys during the Spring Festival dropped by 50% compared with last year. Ten provinces, including Heilongjiang, Beijing, Jilin, Hebei, Tianjin, Shanghai, Chongqing, Zhejiang, Liaoning, and Jiangsu, saw a decline in travel exceeding 55%.

With many people not traveling to spend time with their families this year Baidu has also seen an uptick in the number of visitors to local outside attractions. In Beijing the Summer Palace, Temple of Heaven Park and Beijing Zoo saw a significant increase in visitors during the Spring Festival. In Shanghai the Chenghuang Temple, the Bund, and the Oriental Pearl Tower also saw a large increase of visitors during this year's holiday.

Monday, February 15, 2021

The Flights of the Dictators

Airplane tracking maps like Flightradar24 and FlightAware are a fantastic resource for tracking flights around the world in real-time. However both Flightradar24 and FlightAware don't track all planes. At the request of governments, individuals and corporations some aircraft (often considered sensitive) are not shown on these live tracking maps. A significant percentage of those planes whose flight data is censored are aircraft registered by dictators and authoritarian regimes.. 

That is where Dictator Alert comes in. Dictator Alert is an interactive map showing the recent flight data of dictators around the world. To provide this map Dictator Alert uses flight data captured from from ADSB-Exchange and also from its own antennas installed at different locations around the globe. Dictator Alert checks all flights recorded by ADSB-Exchange and their own antennas with aircraft registered by authoritarian regimes. 

Dictator Alert tracks planes registered by governments described as 'authoritarian regimes' on the Democracy Index (2019). Currently this includes over 200 planes. When the flight of a plane registered to a dictatorial regime is identified by Dictator Alert it is shown on the interactive map, published on the Dictator Alert website and a message posted to the GVA Watcher Twitter account.

The Origins of Stonehenge

It has long been believed that the smaller bluestones of Stonehenge were originally quarried in the Preseli Hills of west Wales. This means that the stones had to have been transported over 200km to the site of Stonehenge. Now new analysis of neolithic human bones found at Stonehenge has provided supporting evidence that over 5,000 years ago people transported stones weighting up to 5 tonnes over 200km from west Wales to the site of Stonehenge.

In the 1920's excavations at Stonehenge unearthed the created remains of a large number of neolithic people. These remains were reburied in 'Aubrey Hole 7'. The remains in Aubrey Hole 7 were excavated again in 2008. Analysis of these remains has identified bone fragments from at least 28 different individuals. By analyzing the strontium found in human bones it is possible to discover where they lived. The strontium isotope composition of bones is related to the composition of the food you eat. The strontium isotope composition of the food you eat is determined by the composition of the soil and the underlying geology. 

The British Geological Survey has mapped the strontium isotope domains of the whole of the United Kingdom. This means that they have a distribution map of the different isotope compositions that can be found across  Britain.You can therefore use this map to discover where an individual grew-up (where their bones were formed) based on the strontium composition of their bones.

You can explore for yourself the geological origins of the neolithic bones found at Stonehenge using the BGS's Biosphere Isotope Remains interactive map. If you enter the strontium isotope composition of an individual's bones into the map you can view a distribution map showing you where the underlying geology in Britain has the same composition - showing you the possible areas where the individual lived.

In the map at the top of this post you can see the results returned from mapping the isotope remains of sample 288 from the remains found in Aubrey Hole 7 (enter the number 0.7109 into the 'Strontium' query on the BGS map). The results show that the strontium isotope composition of sample 288 is very similar to the area of west Wales where the Preseli Hills are located. This individual (sample 288) may not have been involved in the actual transportation of the bluestones from west Wales to Stonehenge but the results of the strontium isotope composition analysis does suggest that in the neolithic era there was migration from Wales to the Stonehenge area and established contacts between Wessex (Stonehenge) and west Wales. 

The strontium isotope composition of sample 288 (0.17109) was taken from the paper by Snoeck, C., Pouncett, J., Claeys, P. et al. Strontium isotope analysis on cremated human remains from Stonehenge support links with west Wales. If you are interested in learning more about the origins of Stonehenge's bluestones then you might also enjoy the recent BBC documentary Stonehenge: The Lost Circle Revealed (possibly UK only).

Saturday, February 13, 2021

Humanitarian Mapping

The Humanitarian OpenStreetMap Team (HOT) is a body which liaises between the OpenStreetMap organization and humanitarian organizations. The team is often actively involved in mapping post-disaster areas and in building better risk models for locations around the world. 

Accurate maps are essential after a disaster strikes, enabling relief agencies and governments to get resources and supplies to the right locations. In the last year HOT has been active during a number of global disasters, including after the Beirut Port explosion, after hurricane strikes in Turkey and Central America, and in response to the worldwide Covid-19 pandemic. In 2020 HOT also created a permanently-staffed global Disaster Services Team (DST).

The DST team has now released an interactive story map 2020 DST Lessons which provides an interesting overview and review of HOT's involvement in nine different post-disaster responses around the world.As you scroll through the map you can read how HOT responded to these different events on the ground. For example, it explains how after the devastating explosion at the Beirut Port HOT led projects to map areas outside of the city center in order to assist planning and service delivery by the Lebanese Red Cross.

The 2020 DST Lessons story map ends with a number of key takeaways. These include recommendations about how HOT can improve its disaster responses in the future.

Friday, February 12, 2021

The Icebreaking Ships of the Baltic

Despite the effects of global heating parts of the Baltic Sea are still often blocked by ice during the coldest winter months. The task of breaking the ice to clear important shipping lanes falls to the icebreakers, ice-strengthened ships which are used to keep the ports and sea lanes open. 

You can view the Baltic's icebreaking ships working in real-time on's Icebreaking and Traffic interactive map. This map shows the current ice conditions in the Baltic Sea and also the real-time position of icebreaking ships and other commercial and recreational marine traffic. 

Different colors are used on the map to show the latest ice conditions on the sea - ranging from light blue for ice free to a dark red for compacted ice. The map menu allows you to select the type of ships shown on the map. This allows you to turn off all other marine traffic and to only track the Baltic's icebreaking ships.

The data on the condition and location of ice comes from the icebreaking authorities of all the Baltic countries. The locations of the ships is determined by the AIS automated tracking system used by marine traffic.

Thursday, February 11, 2021

Historical Maps of New York

The Brooklyn Public Library has a fantastic collection of historical maps of New York City and beyond. The library has digitized around 1,500 of these vintage maps which means that they can all be accessed on-line. The Center for Brooklyn History - Map Collections includes maps dating from the 17th Century right up to the modern day, providing an invaluable resource for anyone interested in the development of New York as the city approaches its 400th birthday.

The collection can be searched by date and by topic. The topics include Land Use, Public Transport and Brooklyn neighborhoods. Each individual map can be viewed as a zoomable image, which allows you to explore the maps almost as if they were full interactive maps.

Part of Ratzer's 1770 Plan of the City of New York

Among the treasures in the library's map collection is one of only four copies of Bernard Ratzer's 1770 Plan of the City of New York. Ratzer was a British Army officer who was employed as a surveyor and draftsman, mostly mapping America's eastern coastline. His 1770 map of New York shows in great detail the city as it existed in the 18th Century.


It is also possible to explore New Amsterdam New York through its history on the NYC Time Machine. The NYC Time Machine includes 27 vintage maps of New York, ranging in date from 1660 to 1924. This collection includes Jacques Cortelyou's 1660 Castello Plan. The Castello Plan is the earliest known map of New Amsterdam. 

The NYC Time Machine use vintage maps from the New York Public Library. The New York Public Library has done a wonderful job in geo-rectifying thousands of historical maps from their collections. An interesting way of exploring the NYPL's collection of vintage maps of New York is ScrollNYC. ScrollNYC allows you to browse through some of the NYPL's vintage maps of Manhattan simply by scrolling down the page. As you scroll a series of static vintage maps of New York appear in chronological order.

Wednesday, February 10, 2021

The Age of Providence

Two new interactive maps have been released which help in the never-ending quest to map the age of every single building in the world. The How Old is Providence? and How Old is Minneapolis? building age maps follow the familiar methodology of coloring individual building plots to represent the decade when buildings were constructed.

The Providence building age map is interactive. Hovering over an individual land parcel on this map will reveal the year of a building's construction. The Minneapolis map is just a static image but there is a zoomable version of the map available which allows you to get a detailed view of different areas of the city. 

Of the two maps the Minneapolis map appears at first glance to be the more revealing. To my untutored eye there appears to be a pattern of more modern buildings existing alongside the Mississippi River. I know nothing about the city but my guess is that this reflects the demise of heavy industry along the river-front and the development of modern apartment buildings in place of those old industrial buildings.

Here are a few other building age maps for cities around the world:

No Fly Free Zones

In response to the more virulent variants of Covid-19 which are now emerging lots of nations around the world appear to be updating their lists of who is and isn't permitted to enter their countries on an almost daily basis. Every day the IATA (International Air Transport Association) updates and releases a new set of rules to explain who is and isn’t allowed to travel into which countries based on the lock-down and travel regulations initiated by countries around the world.

You can now listen to a live broadcast of IATA's daily summary of all the individual state travel restrictions on the No Fly Free Zone interactive globe. This 3D globe uses green and red lines to show flight routes which are currently permitted and prohibited. However the globe's main purpose is the automated broadcast of the IATA restrictions. This broadcast reads out the travel rules for each country around the world in turn.An airport jingle is used to announce the start of each new country's list of travel regulations and requirements.

The No Fly Free Zone interactive globe is the work of artists Mari Bastashevski & Sam Lavigne. The IATA broadcast is updated regularly to reflect the changes in travel regulations as reported on the IATA website.

Tuesday, February 09, 2021

Covid-19 by Satellite

Water quality in the Venice Lagoon during the Covid-19 outbreak

Last summer a number of mapped visualizations were published to visualize the short-term effects of Covid-19 on the environment. As a result of the lock-downs and work at home orders which have been established in many countries around the world there was a marked fall in road traffic in many global cities and a subsequent and consequent improvement in air quality. 

The effect of Covid-19 on economic activity and the environment is not limited to just an improvement in air quality. The global epidemic has also had an observable impact on the Earth's land and water. The COVID-19 Dashboard is a tri-agency project established by the European Space Agency (ESA), the Japan Aerospace Exploration Agency (JAXA), and the National Aeronautics and Space Administration (NASA) to explore the environmental and economic effects of the COVID-19 pandemic on planet Earth.

The Covid-19 Dashboard uses remote sensing data from all three space agencies to investigate and show how Covid-19 has affected Earth’s air, land, and water. For example all three space agencies monitor water quality by measuring Chlorophyll-a (Chl) concentrations using satellite optical sensors. These sensors show that in many locations around the world water quality has improved during the Covid-19 outbreak.

You can explore the map for yourself by selecting either 'Indicators' or 'Countries' from the map sidebar. The available 'indicators' use remote sensing data to explore the effect of Covid-19 on the economy (e.g. air and ship traffic), on agriculture (e.g. planting and harvesting activity) and on air and water quality. The 'countries' menu allows you to select individual countries to view examples of Earth impacts observations available for those countries.

Pointillist New York

Pointillism NYC is an interactive map of New York which uses LIDAR data to show all the city's fabulous skyscrapers in glorious 3D. This 3D map is made from millions of individual dots which together create an incredible map of the city. A map which closely resembles the paintings of Pointillist artists such as Georges Seurat or Paul Signac. 

You can view your favorite landmarks in the city on Pointillism NYC by using the drop-down menu which allows you to quickly pan and zoom to view your favorite New York landmarks, such as the Stature of Liberty, The Empire State Building and the Flat Iron building.

You can learn more about how the map was made on this Impression NYC story map. This map also contains the impressive 3D LIDAR data of Poitillism NYC but also includes information on how the map was made. Both maps use 2017 NYC LIDAR data of New York which was captured after Hurricane Sandy. The data was captured by aircraft which used lasers to create a topographic point cloud of the city. To create a more photo-realistic map each of the individual data points within the LIDAR data were then colored to match the colors in satellite imagery of the city. The result is this incredibly impressive stylized 3D map of New York.

Monday, February 08, 2021

A Living, Breathing Earth

The Digital Twin Sandbox is a fun 3D globe which includes an animated snow layer visualizing the global levels of snow over the course of one whole year. As the globe spins you can view the levels of snow rising and falling across the whole world during the passing of 365 days. 

If all that snow leaves you feeling cold then you can visualize other data on the interactive globe instead. Select the NDVI (Normalized Difference Vegetation Index) layer and you can view the growth and fall of vegetation around the world over the course of the year. 

The data for both the snow and vegetation layers visualized on the interactive globe comes from the Sentinel-2 satellites. You can read more about how the data can be accessed and how the interactive globe was created on the Sentinel Hub blog post, Digital Twin Sandbox Sentinel-2 collection available to everyone.

The Commuting Time Map

The CommuteTimeMap can show you how far you can live from your workplace in order to be able to commute to work within the time you would like to spend commuting. Enter your work (or place of study) address into this interactive map, submit your commuting travel time and an isochrone layer will show you all the areas which you can travel to and from within your commuting time. 

The CommuteTimeMap works for different methods of commuting. You can change your mode of transport for your commuting isochrone between public transport, car, cycling or walking. The isochrone layer showing how far you can travel will change depending on your chosen mode of transport.

At the present time a lot of people might not be in need of a map which shows how far you can commute within a certain time. However the map is still useful for those of us working for home. The CommuteTimeMap includes an option which allows you to view an isochrone layer for more than one address. So, for example, if you want to meet up with a friend outside you can enter both your addresses and see the areas which are within a 15 minute walk of both your homes. You can even ask the map to highlight just the areas which intersects both of your travel areas. 

You can view many more travel time maps by checking out the Maps Mania isochrone label.

Via: WeeklyOSM

Sunday, February 07, 2021

The National Bushfire Map

The 2019-2020 bushfire season in Australia, was truly disastrous and is now referred to in Australia as Black Summer. Around 46,050,750 acres were burned during last year's bushfire season, over 9,000 buildings were destroyed, and nearly 500 people lost their lives.

In January of 2020 a new national bushfire map was released. is an interactive map which uses data from a range of sources to provide a national view of wildfire events in Australia. The map shows current fire hotspots, road closures and information on the latest wind and weather. 

On the map current fire warnings are shown using markers and colored polygons. Locations with fire warnings are shown in red. If you select a warning shown on the map then you can read more detail on the alert level in place, evacuation details & addresses, news on road closures & conditions, and news on the fire-fighting response to the fire.The map also includes an animated wind layer which shows the latest wind conditions across the whole country.

If you register with then you can receive push notifications and alerts about bushfire events near your home.

MyFireWatch is another interactive map providing information on the latest bushfires in Australia. This map uses data from remote sensing satellites and is updated every 2-4 hours, depending on the position of satellites. If you select a fire marker on the map you can read details on the time and date when the fire was last detected and its longitude and latitude.

MyFireWatch also includes an Incidents and Warnings section which provides information on the latest fire warnings issued in each state. 

Saturday, February 06, 2021

Mapping US Vaccine Allocation

During the first phase of Operation Warp Speed the federal government distributed Covid-19 vaccines based on the total adult population of each state. Most states then used the CDC’s COVID-19 Vaccines Work Group recommendations in deciding how those vaccines should then be allocated to their citizens. In Phase 1a the CDC advice was that priority should be given to health-care personnel and long-term care facility residents.

Mapping the New Politics of Care has released a new interactive map which helps to visualize how vaccines could have been allocated in counties during Vaccine Allocation Phase 1a. Using the map you can see how many vaccines each county could have been allocated by the state during phase 1a based on different distribution strategies.The map allows you to directly compare how two different distribution strategies would effect the number of vaccines distributed to each county in a state. 

The different strategies include a simple distribution based on the county's adult population, distribution based on the county's number of health-care personnel and long-term care facility residents, and distribution based on the county's Social Vulnerability Index (excluding the race / ethnicity variable). The numbers used by the map are based on the 22,578,375 doses of the vaccine which were distributed in the United States as of January 18th.

A survey conducted by Carnegie Mellon University’s Delphi Lab suggests that more than 25% of Americans do not want to 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 to target 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 against Covid-19.

Bloomberg's Covid-19 Vaccine Tracker uses data gathered from government websites and public statements to map the progress of the Covid-19 vaccination around the world. The global map shows that countries in the northern hemisphere in general are progressing much faster in rolling out vaccination programs than countries in the southern hemisphere.

The Bloomberg Covid-19 Vaccine Tracker also includes an interactive map which shows the rate that individual states in the USA are administering the Covid-19 vaccination.

Friday, February 05, 2021

Covid-19 School Tracking Maps

The Canada COVID-19 School Tracker is an interactive map which is plotting COVID-19 outbreaks in schools across Canada. The map is designed to provide parents, communities and students with the information to make important decisions about school openings. 

In Canada decisions about school openings are being made at the province level. Unfortunately for parents and students information about Covid-19 cases in schools is not always readily available and some provinces are better than others in reporting outbreaks in schools.

The Canada Covid-19 School Tracker map shows schools which have reported cases of Covid-19. On the map individual schools are represented by colored markers. Yellow markers show where a school has reported individual unlinked cases of Covid-19. Red circles indicate where there have been outbreaks and purple circles show clusters. The size of the circles indicate the total number of reported cases in a school.

The map includes filters which allow you to adjust the schools shown by the number of cases and by date. You can therefore, for example,  use the 'days' filter to only show schools which have reported cases in the last two weeks.

In the UK the School Covid Map takes a different approach. Rather than map the number of Covid-19 cases reported in individual schools the UK School Covid Map shows the number of positive cases reported in the neighborhoods around schools. 

Currently in the UK most schools are closed except for the children of essential workers (e.g. the children of doctors and nurses). The National Education Union has released the School Covid Map to help provide information on whether it is safe to reopen school and colleges. 

The map shows the numbers of Covid-19 cases over the last week in the areas around individual schools and whether the trend in reported cases is rising or falling. The map also shows the watchlist status of the local authority and a link to any local restrictions that are in place.