This article considers the relationship between trade intensity, energy consumption, income per capita, and carbon dioxide emissions from 1970–2016 for the Portuguese economy. Considering the arguments of monopolistic competition, the article tests the hypotheses of trade and energy consumption on climate change. We use the autoregressive distributed lag-ARDL model, quantile regression, and cointegration models such as fully modified ordinary least squares (FMOLS), canonical cointegration regression, and dynamic ordinary least squares (DOLS) as an econometric strategy. The econometric results have support with the literature review. The variables used in this research are integrated with the first differences, as indicated by the unit root test. The empirical study proves that trade intensity contributes to environmental improvements. However, energy consumption presents a positive impact on CO₂ emissions. The econometric results also demonstrated that a sustainable environmental system exists in the long run.

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测试贸易对葡萄牙二氧化碳排放的作用

本文考虑了葡萄牙经济在1970-2016年间的贸易强度，能源消耗，人均收入和二氧化碳排放量之间的关系。考虑到垄断竞争的论点，本文检验了关于气候变化的贸易和能源消耗假说。我们使用自回归分布式滞后ARDL模型，分位数回归和协整模型（例如完全修改的普通最小二乘（FMOLS），规范协整回归和动态普通最小二乘（DOLS））作为计量经济学策略。计量经济学结果得到了文献综述的支持。如单位根检验所示，本研究中使用的变量与第一个差异集成在一起。实证研究证明，贸易强度有助于改善环境。然而，₂排放。计量经济学结果还表明，从长远来看，存在可持续的环境系统。