Sankey Diagrams

On Wiki Commons I discovered a different Sankey diagram image for the greenhouse effect than the one I presented in a previous post. The diagram is titled ’sun climate system’, which seems appropriate.

It is in German, but if you want to know what the labels mean, just go to the original Earth Observer (Nov/Dec 2006 Vol. 18 Issue 6) PDF file by NASA and check out page 38.

The values are in Watt per square meters. The “quantities in parenthesis indicate changes in global heat flows” over 10 years time.

Doing a Google image search on ‘greenhouse effect’ brings up numerous versions of a diagram, that shows solar radiation partially being filtered by the atmosphere, partially hitting earth’s surface. This energy heats the earth, a part is being reflected as infrared radiation, where it is not able to escape fully due to greenhouse gas molecules from man-made emissions’ accumulated in the atmosphere.

While some of these greenhouse effect diagrams use simple arrows, some of them show the energy levels with Sankey-like arrows.

Wikipedia has one of these as an illustration for the article on the greenhouse effect. Originally designed for Global Warming Art it is also available in the Wikimedia Commons in Finnish and in Japanese.

Many of the “normal” diagrams are very appealing, and I especially like the one’s that target at kids or students. However, the diagram using Sankey arrows conveys more information. Check for yourself by comparing the two examples above.