Based on the previous study, the causality between GDP per capita, Trade Openness and CO2 emission:2.1.1 GDP per capitaThe prior study showed that Zambrano-Monserrate, et al (2016) GDP per capita have prove that inverted U relation which is EKC between economic growth and CO2 emission . CO2 emission is increasing along the economic growth up to a turning point at which emission start to decline. Han Xuemei et al. (2011) state that GDP have causality with emission of soot and emission of sulphur dioxide. Same goes to other study which is Hettige et al. (1992), Cropper and Griffiths (1994), Grossman and Krueger (1995) and Martinez-Zarzoso and Bengochea-Morancho (2004) shows that GDP per capita have causality with emission of pollution, which state when the GDP per capita is increasing the emission of pollution also getting worst . Next study from J.B. Ang (2007) had state that the pollution keep increasing as the per capita GDP increase. Selden and Song (1994) in their study was using cross national panel data. In their study mention that there is relationship between the per capita GDP and the emission of pollution . Next is Boa and Shuijun (2006). in their research is to examine the relationship between pollution emissions and per capita income in China and also they had mention about kuznets inverted-U curve relationship and China’s economic growth.From the other research by Han X.M and Zhang M.L, (2011) emphasize the relationship between the economy growth and environment within China province. This is because some previous research their conclusion between emission of key industrial pollutant and average per capita income from developed countries do not correspond to the truth of developing country.2.1.2 Trade OpennessBase on study by Stern et al. (1998), Suri and Chapman (1998), Cole (2004), Arrow et al (1995) and Rothman (1998), trade openness there are causality in the CO2 emission and also exist of the Environmental Kuznet Curve (EKC) hypothesis between them. Mizan and Halimaton(2012) their study is to investigate the impact on quality of life in Malaysia from 1965 to 2015. In their study the import decrease the industrial CO2 emission while the export increase the industrial CO2 emission. It might because the of the geographic location to the effect of environmental quality. Arouri and Shahbaz (n.d.) reported that on 1971-2010 in Thailand, the observe trade openness have bidirectional causality with carbon dioxide emission that explain the trade openness lack of enforcement from the state to make policies. Thus showed that EKC is exist between trade openness and pollution. Economic growth Granger causes CO2 emission further ratification the presence of EKC in Thailand. 2.1.3 Carbon Dioxide, CO2 emission. Based on Hossain (2011), reported that CO2 emission is getting worst since the energy consumption also increase thus the environment quality become lower. He also found that the variable such as the trade openness and urbanization do not have correlation to the CO2 emission. In this study he was using nine newly industrialized countries (NIC) such as Brazil, China, India, Malaysia, Mexico, Philippine, South Africa, Thailand and Turkey to study the relationship between CO2 emission, energy consumption, economic growth, trade openness and urbanization. Next is exist of cointegration between the variable which is CO2 emission, GDP per capita, energy use and electricity production from the hydropower sources (Monserrate, 2016). Same to other previous study the CO2 emission increase as the economy grow but then it start decreasing once the per capita figure reaches a certain threshold. Expectation from this study there is sign of coefficient to long run relationship between the variable and environmental degradation measure by the CO2 emission. Thus as there is a growth of economy in Brazil, it will give negative impact on the environment would be reduce. In additional, the GDP per capita causes CO2 emission in the long run.Based on research by James (2007) on France , the causality result support the argument that economic growth exerts a causal influence on growth of energy use and growth of pollution in the long run and also pointed to a uni directional causality running from growth of energy use to output growth in the short run. He was using cointegration and vector error correction as the modelling technique to determine the correlation between the variable. The variable in this study is pollution emission, energy consumption and output in France. 2.1.4 Environmental Kuznet Curve (EKC) There is several empirical EKC model which support the inverted U-shaped relationship between pollution and income by using the elasticity of income on demand for environmental quality in the EKC hypothesis. Lopez (1994) reported in his research explain people will pay their tax fees of population since the pollution is getting higher. When there is inverted U-shaped curve on EKC it shows people demand a better quality of environment when they have a better income, thus it is acceptable to environmental quality (Arrow et al,1995). Unfortunately, McConnell’s (1997) result showed the pollution is increasing with consumption but in small value when there is higher positive income elasticity of demand on the environmental quality but the pollution decrease with consumption since the study conclude that pollution can decrease the output when labor productivity decline resulting from health issues and damage caused by the climatic condition, even though the income elasticity of demand is zero or negative. In this research have mention that relationship between income and pollution do not have correlation to inverted of U-shape for EKC. Same goes to Fodha and Zaghdoud (2010) study between cointegration between environmental quality such CO2 emission and economic growth in Tunisia by using EKC hypothesis. There is a study in Turkey to determine relationship between economic growth and CO2 emission (Arbostanci et al., 2009). Another study based on 36 high income countries to investigate the correlation between CO2 emission and economic growth (Jaunky, 2010). All of these study conclude that the EKC hypothesis is not exist between these variables.There are a lot of study show the relationship between economic growth and CO2 emission, from that relationship prove that there is exist of Environmental Kuznet Curve (EKC) hypothesis. For instance Poa and Tsai (2010) for BRIC; Orturk and Acaravci (2010) for Turkey; Acaravi and Orturk (2010) for Europe; Nasir and Rehman (2011) and Shahbaz et al. (2012) in Pakistan; Iwata (2011) in 28 developed and developing countries; Saboori et al (2011) in Indonesia; Saboori et al. (2012) in Malaysia; Shahbaz et al. (2013) for Romania and Tiwari et al. (2013) for India.