Tag: GHG

Greenhouse Effect Explained with Sankey Diagram

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.

Greenhouse Gas Emissions in the U.S.

The Energy Information Administration (EIA) of the U.S. Department of Energy (DOE) publishes an annual report on the Greenhouse Gas Emissions in the US economy. The executive summary of the 2005 report shows a Sankey diagram on page xv.

This Sankey diagram shows on the left side the different sources of CO2 (mainly combustibles), and on the right hand side the industrial sectors (residential, commercial, industrial and transport) that contribute to the CO2 release. Emissions are in million ton CO2-equivalents.

The original Sankey diagram from the report has been reproduced with the e!Sankey software, and is shown below. Footnotes have been omitted, for full detail please refer to the original source.