پرویز حاجیانی

Background: Nowadays, the substantial increase of environmental pollutant gases such as the greenhouse gas carbon dioxide as a result of growth and industrial development has attracted more attention in order to prevent the harmful effects of greenhouse gas in developed and developing societies in recent decades. Several factors such as economic and demographic factors can play a role in the release of the greenhouse gas carbon dioxide. The impact of these factors can be different in each country according to specific conditions economic, demographic, environmental, etc. Aim: The aim of this study is to investigate the relationship among environmental pollution indicators (carbon dioxide) and variables of population growth and energy consumption per capita to determine the type and intension of their relationship, to implement policies and compliant strategies with sustainable development. Methodology: This study has been explored the relationship among the carbon dioxide emissions per capita, population growth and energy consumption per capita"s variables for the period 1990-2012 in OPEC, and also has been investigated to determine the share of each factors in carbon dioxide per capita emissions changes period of the time, by applying Two-Stage Seast Squares method of simultaneous equations system approach to analysis relationships among variables and decomposition approach IPAT structural model and with the use of econometric methods panel data and by using Eviews software. Conclusions: According to the results, the first hypothesis based on the direct relationship between the energy consumption and CO2 emissions is confirmed, but the second hypothesis based on the direct relationship between population growth and CO2 emissions can be rejected, also according to the results of the decomposition method the highest share in emissions of carbon dioxide gas per capita changes depended on the structural effect of the total population and the impact of energy consumptio