Friday, February 27, 2015

Visualizing Ten Years of OpenStreetMap

Mapbox has released an animated map visualizing the growth of OpenStreetMap data over the ten years since the project started. Ten Years of OpenStreetMap shows how OpenStreetMap has grown in ten years from a map of a few London streets to one of the most detailed maps of the world.

The animated map reveals how OpenStreetMap has particularly developed in the last 5 years from largely a map of the United States and Europe into a truly global map.

Martin Raifer's OpenStreetMap Node Density also provides a general overview of OpenStreetMap's global coverage. Each pixel on the map shows the number of nodes at that location. Martin Raifer's map shows OpenStreetMap node density as of June 2014.

Of course OpenStreetMap is an ongoing project to map the world. The world is always changing and OpenStreetMap needs to reflect those changes. Therefore dedicated volunteers around the world are always working to improve the map.

OSMlab's Show Me The Way provides a real-time view of OpenStreetMap's contributors in action. Using satellite imagery from Bing Maps 'Show Me The Way' provides a captivating visualization of the ever improving OpenStreetMap project.

Thursday, February 26, 2015

Animated Heat Maps of Weather Data

A few weeks ago CartoDB released CartoDB Heat Maps. This new heat maps option in CartoDB leverages the power of the Torque library, which allows developers to efficiently render and publish very large datasets to the client.

CartoDB Heat Maps can also be used with Torque to create animated heat maps. Where this could be particular useful is in visualizing weather data and patterns. For example, check-out this map of historical Hurricane and Tropical Cyclone Track Density. The map animates the track density of hurricanes and tropical cyclones from 2000-2013, using data from the National Climatic Data Center - NOAA.

Not to be outdone Mapbox has been playing with the latest update of Turf.js to create animated heat maps of historical U.S. hail data. Turf now includes powerful new functions to aggregate dense point data into grids and heat maps. Mapbox has created a demonstration of this new heat map ability in a blog post, Animated Heatmaps and Grids with Turf.

The map not only shows an animated heat map of historical hail data but also allows you to view the data as animated hexbins, triangles, squares and points. The map also includes the option to view the animated data in three different speeds.

US River Mapping

Hydro Hierarchy is a map of the largest rivers in the United States and their monthly river flows. Select a river segment on the map and you can view a chart of its 2014 monthly river flow.

The horizontal red line on the bar chart represents the ten year mean monthly flow, which means you can compare each month's river flow to its yearly average. The 2014 drought means that on most river segments most months will be below the ten year average.

The radial chart to the left of the map is a hierarchical representation of the stream network. If you mouse over to the center of the chart you can view river terminations at the ocean or international borders.

Hydro Hierarchy only visualizes rivers and streams with a Strahler stream order classification of four or greater. Andrew Hill has created a map of all United States rivers in which the rivers are colored by the direction of flow. The U.S. Rivers Colored by the Direction they Flow map shows the colored river locations on a black background to create a visually striking map of the United States.

The map uses data from Nelson Minar's Vector River Map, which in turn uses river flow data from NHDPlus. Andrew has also used the same river data to create another beautiful map. Rivers with Rainfall. This map shows U.S. rivers and rainfall in the last hour. The rain data comes from a National Weather Service data feed.

You can read more about the Hydro Hierarchy map on the Esri Blog and download the source code on the Esri website.

Wednesday, February 25, 2015

The New York Time Machine

Every time I make a good map I soon find out that someone has done it better. Recently I've spent a lot of time creating vintage map browsers with the Leaflet mapping library. I used the New York Public Library's map collection to put together a map of New York Vintage Maps. I then used the amazing David Rumsey Map Collection to create a map of San Francisco Vintage Maps.

Well it turns out that Vestiges of New York has created a better collection of New York vintage maps, using vintage maps from both the NYPL and the David Rumsey collection of historical maps. Their NYC Time Machine is very similar to my map, except it has far more vintage maps of New York maps for you to browse through.

The NYC Time Machine includes 27 vintage maps of New York, ranging in date from 1660 to 1924. The map includes a neat option to quickly switch between your chosen vintage map and a modern map, allowing you to compare the vintage map to the modern streets of New York.

Mapping African Democracy

President Teodoro Obiang Nguema Mbasogo of Equatorial Guinea and President Jose Eduardo dos Santos of Angola have both been leaders of their respective countries for 35 years. According to the Economist neither country qualifies as a full democracy. There are 27 countries in Africa ruled by an authoritarian regime or a nominal democracy. The Economist claims that Mauritius is the only African country to qualify as a full democracy.

In a series of interactive maps The Guardian has mapped various indicators of democracy and government in Africa. Using data from the Economist Intelligence Unit Democracy Index 2014, the CIA Factbook, the World Intellectual Property Organisation and Intellectual Ideal the newspaper has mapped out the presidential term limits, voter turnouts and the longest serving leaders in African countries.

Power in Africa: Democracy Mapped uses CartoDB to present a series of interactive maps showing the state of democracy, the number of registered voters and the number of voters in African countries. It also includes maps of presidential terms limits and the lengths served by Africa's current leaders.

Mapping Shrinking Glaciers

Alaska Ice: Documenting Glaciers on the Move is an Esri Story Map which uses satellite imagery and comparisons of modern & vintage photographs to document Alaska'a glaciers.

The main focus of the map is the U.S. Geological Survey's Repeat Photography initiative. USGS has been comparing modern photographs of Alaskan glaciers with historical photos, both with the same field of view. The photographs are compared to document and understand the changes to glaciers resulting from changing climate.

The Alaska Ice Story Map visits 14 glaciers in the U.S. state. Each glacier can be viewed on a satellite map and a modern and an historical photograph of each glacier is compared in the map sidebar. Of the 14 mapped Alaskan glaciers only two are still advancing.

Disappearing Glaciers is another Esri StoryMap, this one is designed to highlight the alarming speed at which glaciers are disappearing around the world.

The map looks at recent aerial imagery of six different glaciers. Polylines have been overlaid on each glacier aerial image to show the glacier's size through time, demonstrating how far each glacier has reduced over the years.

Timelapse - aerial imagery of the Mendenhall Glacier in 1991 & 2012

Another interesting way to examine the loss of glaciers is with Google Timelapse. Timelapse allows you to compare aerial imagery over time for any location on Earth. You can therefore enter the name of any glacier into Timelapse and observe the effects of global warming for yourself.

Timelapse provides links to the Medenhall Glacier and the Columbia Glacier but you can use the search box to locate any glacier. You can therefore use Timelapse to search for the six glaciers used in the Disappearing Glaciers map and observe the highlighted loss of each glacier for yourself, using the historical aerial imagery.

Tuesday, February 24, 2015

Google Paper Maps of Europe

According to the UK's Ordnance Survey paper maps are beginning to make a comeback. This should be welcome news to USE-IT, creators of printable mapped city guides.

USE-IT has created a series of mapped guides to a large number of Europe's major cities. The maps are aimed at the young independent traveler and are full of fun things to see and do in Europe's cities. They are also free to print straight off the USE-IT website.

If you still prefer your maps to be interactive and digital then you don't need to worry. USE-IT has also used the Google Maps API to create zoomable versions of each of its paper maps.

3d Art View of the World

Culturalmap is trying to create a map of 3d scans of cultural objects around the world. The map consists at the moment of a few 3d scans, created with Sketchfab, which allow you to explore the 3d models of a number of historical statues and busts.

You can see an example in the screenshot above. On the map you can rotate the Colossal Bust of Zeus and explore this cultural artifact from all angles by interacting with the 3d scan.

It appears that I've caught this map at a very early in its release schedule. The map doesn't yet have many 3d scans and the linked Twitter account has yet to post any content. However, from reading the 'Learn' page, it appears that Culturalmap is planning to crowd-source the cultural 3d scans, which hopefully will eventually lead to a more populated map.

Map in GeoHipster Blue

Plain Tile Maker is a series of 675 blank map tile schemes, each one in a different color. Using the app you can serve simple block color map tiles to any of the major mapping libraries.

The tiles can be added to a map using the following URL:[colorname]/X/Y/Z.png

The 'colorname' in the URL can be any of 675 different colors. The 'colorname' must conform to one of these ImageMagick Color Names.

At first I thought that the Plain Tile Maker was meant as a joke. However, thinking about it, these plain color tiles could be useful if you want to serve your own map data (for example river courses or building footprints) without any underlying map data. The Plain Tile Maker allows you to set your own background color scheme for your map data or could be used to give users a choice of background colors for your map data.

Just in case 'colors' are a new concept to you I've put together a small Leaflet.js map using a few of the different map tiles. Colors allows you to view a blank Leaflet 'map' in your choice of six different colors.

Iceland's Rival to Street View

Iceland's telephone and business directory company Já has released 360° panoramic imagery of the country's roads.

Já maps uses Samsýn map data with the Leaflet mapping platform. If you select the '360' link in the map menu the availability of Street View is displayed on the map with blue lines. The coverage rivals Google Maps Street View coverage in Iceland, with 360° panoramic imagery available in towns and cities and all major roads.

The date that the imagery was captured is displayed in the bottom right-hand corner of the map. Most of the imagery seems to date from August 2013. Most of Google Maps Street View imagery dates from the same time.

In fact we know that the Google Street View car and the Já maps car were on the streets of Iceland at the same time because the two cars were busy capturing photos of each other. Street View Fun managed to find this scene, where the Já maps car is happily following along behind the Google Street View car, while they both capture their panoramic imagery of Iceland (and each other).