Three-dimensional ecological footprint and economic complexity nexus in GCC countries

The ecological footprint is unable to separate stock capital from flow capital and measures only natural capital. In this study, the three-dimensional ecological footprint was measured for the Persian Gulf Cooperation Council (GCC). For the first time, the three-dimensional ecological footprint (EF_3-D) and economic complexity nexus were examined in GCC countries, and the results are compared to the classical ecological footprint (EF_2-D). The quantile regression method was used to investigate the impacts of economic complexity, population, economic growth, and energy consumption on different quantiles of EF_2-D and EF_3-D over the period 2000–2017. The results indicated that, in addition to its ecological benefits, economic complexity can effectively decouple environmental sustainability from both EF_2-D and EF_3-D in GCC countries. Additionally, empirical findings supported an inverse U-shaped relationship between both the three-dimensional and traditional ecological footprints and economic growth at all quantiles. Moreover, population and fossil fuel energy were found to have a positive effect on EF_2-D and EF_3-D in GCC countries. Based on these findings, policymakers are advised to propose comprehensive policies that target not just the size but also the depth of ecological footprints.