The first one shows French wine exports in 1864. A lot of the good stuff goes to European neighbours, the U.S., to Brasil, Uruguay and Argentina [the latter today an exporter of great wines themself]. But there are also some gourmants that appreciate ‘un verre de bon rouge’ in remote places such as India, China, and of course the outer French territories (Mauritius and Reunion). Not sure what the unit of flow is, as the image is to small to read.

The second one is a map of France that shows the transport of wine and spirits in 1857. Most of the good stuff is shipped to Paris along rivers (green) and major railway lines (pink). Road transport seems to have been excluded. You can also see the transports to the ports for exports (yellow). Flows are in tonnes, but the band itself shows transports in both directions. This national map could be seen as an inset into the above map.

What differentiates Minard maps from Sankey diagrams is that Minard’s fine works always have a geographical relation. The most famous one is his Map of Napoleon’s march to Moscow published in 1869. This “carte figurative des pertes successives en hommes de l’Armée Francaise dans la campagne de Russie 1812-13″ shows number of men (as width of arrows), geographic movement of the troops on the map both for invasion as well as for retreat, as well as time and temperature on a separate scale.

Cartographia blog has some other nice examples, two of which are shown here:

The first shows migration patterns across the globe. Arrows do not have an arrow head but the country of emigration is color coded. The outline of the countries is distorted to accomoadate large flows connected to them. For a detailed description please consider reading the original blog post. This map is similar to the one I showed in this post.

The other is a flow map for wool and cotton for the years 1858 and 1861. “Blue represents cotton and wool from the United States, the orange from British territories in South Asia … One millimeter represents 5,000 tons of cotton or wool.”. As one can see on the 1861 map, cotton imports from Asia have increased dramatically. See the description of the map in the blog post on Cartographia blog.

See all Monday’s with Minard posts here. There has been no activity on the blog since June 2008. I hope to see more of these posts some day.

You can see the oil imports to the United States from January 1973 to August 2008 on a map that depicts the flow quantities as Sankey arrows linking the country of origin and the U.S. If you switch to the unit “Dollar”, you can see the value of the oil imported depicted as Sankey arrows.

One can play the the whole 35-year period as a movie, or use the slider on the time line to see individual months. The data used is from publicy accessible EIA/DOE statistics.

The United States is still 60 % dependent on imported oil. MRI’s MOVE project seeks possibilities to reduce foreign crude oil dependencies. The goal is to “get completely off oil by 2050, led by business for profit.”

Go to the RMI movie page and try it yourself. When I did the Lybia Oil Export map last year I wasn’t aware of this Sankey movie, which is of course much nicer.

The best one I have seen was in this summary report on ‘Europe’s Demographic Future’ published by Berlin Institute for Population and Development. On page 11 you can see the migration flows within Europe (with omissions). The widest Sankey arrows are for migration movements from Bulgaria and Romania, mainly to Spain. There seems to be a lower cut off threshold at approx. 10.000, which leads to smaller flows not being scaled linearly any more. A lot of interesting details in this one… [would have loved to reproduce it, but permission wasn't granted].

Here are other samples for Sankey diagrams visualizing migration flows (no quantities given, exact time range unknown).

Emigration flows to North and South America in the first half of the 20th century

Refugee flows in Middle East, Africa and Asia in 2006 (clustered quantities)

Both diagrams found on My Paris Your Paris blog

I think Sankey diagrams in this context merit more attention. Will be looking for more of these…

I wanted to do a Saudia-Arabia or Irak oil export Sankey map, but couldn’t find good data. I finally came across this summary on Lybian oil exports, and converted the data from the pie chart Lybian Oil Exports, by Destination, 2006 to a Sankey style export flow diagram.

It was new to me that “Libya has the largest proven oil reserves in Africa” with 41.5 billion barrels, and estimated net exports of 1.525 million barrels per day in 2006.

The underlying map is a crop from a World map found on Wikicommons. I think it could be a little more transparent though…

This reminded me of the internet traffic maps I had seen on the Web before. These are available as traffic load maps as well as bandwidth capacity maps of the backbone infrastructure.

Indeed these maps can be considered as fine examples of Sankey diagrams, with bi-directional (or non-directional?) arrows whose magnitude represent the bandwidth of the transcontinental internet cables. Additional arrow colors could be used, for example, to represent ownership or operation of the cable by different companies.

At the same time the Sankey maps may also serve to indicate communication technology development in different world regions.

BTW, if you want to stick one of these maps prominently on your office wall, they are available as posters here.