Abstract:
Carbon dioxide (CO2) emission has an essential role in the current debate on sustainable
development and environmental protection. CO2 emission is also directly linked with use
of energy which plays a focal role both for production and consumption in the world
economy. Therefore the relationship between the CO2 emission and economic growth
has a significant implication for the environmental and economical policies. In this study,
within the scope of sociophysics, the topology, taxonomy and relationships among the
33 countries, which have almost the high CO2 emission and economic growth values, are
investigated by using the hierarchical structure methods, such as the minimal spanning
tree (MST) and hierarchical tree (HT), over the period of 1970–2010. The average linkage
cluster analysis (ALCA) is also used to examine the cluster structure more clearly in HTs.
According to their proximity, economic ties and economic growth, different clusters of
countries are identified from the structural topologies of these trees. We have found that
the high income & OECD countries are closely connected to each other and are isolated
from the upper middle and lower middle income countries from the MSTs, which are
obtained both for the CO2 emission and economic growth. Moreover, the high income &
OECD clusters are homogeneous with respect to the economic activities and economic ties
of the countries. It is also mentioned that the Group of Seven (G7) countries (CAN, ENG,
FRA, GER, ITA, JPN, USA) are connected to each other and these countries are located at the
center of the MST for the results of CO2 emission. The same analysis may also successfully
apply to the other environmental sources and different countries.