This paper proposes a comprehensive decomposition method to estimate how changes in domestic economic scale, industrial composition, domestic technology, export scale of intermediate products, export composition of intermediate products, export scale of final products, export composition of final products, import scale of intermediate products, import composition of intermediate products, import scale of final products, import composition of final products, and foreign technology affect the volumes of both territorial CO2 emissions (including emissions induced by producing exports) and extraterritorial CO2 emissions induced by imports. Specifically, the sources of the territorial CO2 emissions of each of 40 nations from 1995 to 2009 were examined using the Environmentally Extended World Input-Output Tables in 2009 prices. Based on the results, the patterns of structural change in the 40 nations can be classified into eight types and it can be seen that domestic industrial structure changes and import structure changes have different roles according to the group types. This study demonstrates the need for global warming countermeasures that consider the differences in the role that each country's structural changes play in CO2 emissions. We also found that the export composition effect was negligibly small in both the high-income and middle-income group of countries during 1995-2008 and it has not played an important role in climate change.