Merian who runs the Boreal Perspectives blog posts on a Sankey diagram that visualizes academic career paths.

This was originally shown in a 2010 Royal Society policy report entitled “The Scientific Century: securing our future prosperity”. Merian raises concerns about the quality of the diagram. She goes: “So what’s so bad about the chart? Some obvious issues:

  • It is unclear what goes in on the left and to a lesser degree what is covered by the end points. The report indicates in a footnote that the term “science” is used “as shorthand for disciplines in the natural sciences, technology, engineering and mathematics,” but the three documents used for input categorise the fields in different ways, and there is no indication which fields exactly would have been selected.
  • Line thickness is not proportional to percentage weight. The 26.5% and 30% streams have the same thickness, and the 17% stream is much less than half the thickness of either. The 3.5% stream is more than half the thickness of the 17% stream.
  • Why does “Permanent Research Staff” not end in an arrow? And why does the arrow from “Permanent Research Staff” to “Careers Outside Science” bend backwards (to suggest it is a step back in one’s career, that is, an implicit value judgement?) and then not even merge with the output stream?
  • Does it really mean to suggest that no one goes from “Early Career Research” (that is, a post-doc) to “Career Outside Science” (or to industry research)? In my experience, watching post-docs, that is quite a common choice for post-docs precisely because non-academic jobs may be offering better pay and conditions, or because they don’t have a choice at that stage.”

She then presents a remake of the above diagram made using the Sankey plugin for d3.js

Indeed, the distribution diagram without the arrow heads seems to be better suited. The overall appearance is much more calm.

Merian, however, concludes “no graph would have been more useful”.

A research group headed by Andrew Skelton and Sören Lindner at Cambridge University’s Centre for Climate Change Mitigation Research is “developing environmentally extended input-output models to assess greenhouse gas reduction across production layers and supply chains of the global economy.”

The figures on their webpage describing the group’s activities include this Sankey-style mapping of “flows of embodied emissions through the global economy [that] … help to visualise and explain … differences between production-based and consumption-based accounts of emissions”.

Unfortunately no high-res image is available. However, one can find the producing sectors on the left side (each of which identifiable by its own color) and their responsibility for a share of the 22.76 Gt direct CO2 emissions. On the right side one can see the consuming sectors and their use of input that has embodied emissions from the supply chain (two intermediate transformation steps in the centre).

Additionally one can find these two diagrams for embodied emissions from supply chains. The left one is for all major non-EU sources, the right one a breakdown for products and intermediates sourced from China.

Data is based on input-output (IO) statistics and Life Cycle Assessment (LCA). An interesting topic and a good use of Sankey diagrams IMHO. Read more on the research web page that also has links to the scientific publication made by the group.

This Sankey diagram of energy flows in a “pusher type reheating furnace” illustrates an article on ‘Reheating Furnaces in Steel Plants’ by Satyendra on the ISPAT Guru blog.

Unit of flow is not clear, but the main stream arriving from the top represents the baseline 100% (508 units) of which a portion can be recuperated and fed back into the furnace as preheated air.

From the Swiss Energy Statistics for 2005 published by BFS comes the following Sankey diagram.

Flows are in GWh. The large pale streams on the left are imports and exports. The vertical bands are domestic energy production (different types of electricity generation) at the top. A breakdown of the consuming sectors is shown in the lower part.

Will try to dig out a more recent energy balance for Switzerland to compare.

A web page of the federal german ministry for Environment, Climate and Energy in Baden-Wurttemberg informs companies about energy efficiency. Sankey diagrams are described as a useful instrument to detect hotspots for improvement and a tool in the framework of energy efficiency analysis.

The Energy Education References Wiki has a page on Sankey diagrams. It features many samples, snippets and links directed at teachers.

One image in particular caught my attention. This is described as “Energy Display System” created by CSIS in the 70s


(via Energy Education References Wiki)

You all know those national energy flow Sankey diagrams I show here regularly? Now imagine the same type of image as a series consecutive frames for several years. This would produce a kind of animated gif or movie showing changes over time.

The above must be an early 3D version of this. The diagrams are mounted on what seems to be acrylic glass…

Funny post on German blog “Trinklaune” by Robin Stein. He suggests using Sankey diagrams to control loss of spirits in a pub. Apparently this was kind of a student project.

Here we see the Sankey diagram for a Negroni cocktail made up from equal parts of Gin, Campari and Vermouth rosso.

On every bottle a certain quantity is lost. This is probably because bartenders put in more spirit than they should, or offer free drinks, or maybe just drink it themselves…

As we can see in this figure, losses can add up considerably in a bar that serves several drinks.

Regular readers of this blog have seen the national energy flow diagrams (energy balances) before. I have featured them from many different countries already.

I finally came across a similar Sankey diagram the energy flows of Europe for 2010. It is featured on the European Energy Agency (EEA) website in a report titled ‘Overview of the European energy system (ENER 036) – Assessment published Mar 2013′.

“The figure is a Sankey diagram which shows the composition of the primary energy entering the energy system of the EU-27 in 2010, and where this primary energy was used, either as losses or as consumption by specific sectors of the economy”. It is based on EUROSTAT data for the EU-27 countries.

A legend is available below for the coloured arrows. The diagram is extensively explained and commented on the web page.

In addition to what we have seen in such diagrams, the primary energy (fuels) is further differentiated with two separate input flows whether the energy carrier was imported or is from domestic European production. This is to visualize dependency on imports.