Global pattern of the international fossil fuel trade: The evolution of communities

In the international trade of fossil fuel, countries are clustering into communities. The evolution of the communities can reflect the underlying trade pattern. This paper provides a new perspective in analyzing the global pattern of international fossil fuel trade by quantitatively analyze the evolution of the communities. Emergy transformity are used to unify the three different fuels into the same unit seJ. This paper creates network models of fossil fuel as well as coal, crude oil, and natural gas and detected the clustering of the countries by an algorithm. Three types of Normalized Mutual Information are designed to measure characteristics of the evolution of the communities. A matrix is also designed to show the flows between each two communities.