The role of ecological footprint and the changes in degree days on environmental sustainability in the USA

The effect of renewable energy on carbon emissions through globalization

The sustainability of the environment debate cannot be addressed without considering the type of energy to use. The pace at which the world is industrializing, globalizing, and developing economically has prompted many researchers to investigate the kind of energy required to preserve the environment. In this regard, this study employs the mediation model to assess renewable energy's direct and indirect effects on carbon emissions through globalization. The data for the study is from 1990 to 2020. The study's findings showed that while renewable energy has no appreciable impact on trade openness, it directly and negatively affects carbon emissions. However, foreign direct investment has a direct and significant positive effect on carbon emissions, while trade openness has no significant effect. The indirect result revealed that renewable energy through foreign direct investment has a negative effect on carbon emissions; however, renewable energy through trade openness has a positive effect on carbon emissions. Policymakers are encouraged to restrict the trade sector to reduce the trading of high-emission technologies.

The intermittent effects of renewable energy on ecological footprint: evidence from developing countries

This paper examines the relationship between renewable, non-renewable energy, natural resources, human capital, and globalization on ecological footprint from 1990 to 2016 for developing countries. We apply Westerlund co-integration technique to check the long-run relationship among the variables. The long-run elasticity of the model is analyzed through MG, AMG, and DCCE. For the robustness check of the long-run relationship among the variables, we use FMOLS and DOLS approach. The direction of causal relationship is determined through Dumitrescu and Hurlin causality test. Our findings revealed that economic growth, non-renewable energy, natural resource, and urbanization are inducing the ecological footprint of developing countries and reducing the environment's quality. To cope up with this situation, developing countries are bound to use more fossil fuel energy. The use of non-renewable energy consumption leads to increase the extraction of natural resources like coal and oil. However, renewable energy reduces the ecological footprint or improves environmental quality. Similarly, human capital and globalization have negative effects on ecological footprint. The results of causality test reveal that there are feedback effects between ecological footprint with economic growth, globalization, and natural resources. This study suggests that these developing countries should focus more on the investment in the renewable energy sector, improve quality education, and make stringent environmental policy for protecting the nations from ecological issues.

Pathways to progress sustainability: an accurate ecological footprint analysis and prediction for Shandong in China based on integration of STIRPAT model, PLS, and BPNN

The world has been challenged by achieving the plausible goal of sustainable development. This study aims to evaluate the ecological footprint and ecological carrying capacity and their driving factors of Shandong province in China from 1994 to 2017. Back propagation neural network method is adopted to predict the ecological footprint from 2018 to 2030. The findings are as follows: (1) The growth of ecological footprint has caused the ecological deficit in Shandong. (2) With regards to population, the increase of total population and the urbanization rate will incur the expansion of ecological footprint. (3) In terms of affluence, the elasticity coefficients of GDP per capita, the production value of industrial sectors, and the proportion of output value of the secondary industry in GDP are 0.068, 0.064, and 0.130 respectively. (4) In terms of technology, the elasticity coefficients of internal expenditure on R&D in GDP and patent number are 0.096 and 0.047 respectively, indicating that technological progress can promote ecological footprint in a short term. (6) The results of the prediction show that the ecological footprint of Shandong from 2018 to 2030 in the policy-regulation scenario is far less than that of the business-as-usual scenario. The policy recommendations are suggested to tackle the sustainable development challenges.

Application of a Combined Adsorption−Ozonation Process for Phenolic Wastewater Treatment in a Continuous Fixed-Bed Reactor

This work studied the removal of phenol from industrial effluents through catalytic ozonation in the presence of granular activated carbon in a continuous fixed-bed reactor. Phenol was chosen as model pollutant because of its environmental impact and high toxicity. Based on the evolution of total organic carbon (TOC) and phenol concentration, a kinetic model was proposed to study the effect of the operational variables on the combined adsorption–oxidation (Ad/Ox) process. The proposed three-phase model expressed the oxidation phenomena in the liquid and the adsorption and oxidation on the surface of the granular activated carbon in the form of two kinetic constants, k1 and k2 respectively. The interpretation of the constants allow to study the benefits and behaviour of the use of activated carbon during the ozonisation process under different conditions affecting adsorption, oxidation, and mass transfer. Additionally, the calculated kinetic parameters helped to explain the observed changes in treatment efficiency. The results showed that phenol would be completely removed at an effective contact time of 3.71 min, operating at an alkaline pH of 11.0 and an ozone gas concentration of 19.0 mg L−1. Under these conditions, a 97.0% decrease in the initial total organic carbon was observed.

Environmental sustainability statement of economic regimes with energy intensity and urbanization in Turkey: a threshold regression approach

In recent time, the investigation of the state of environmental quality has largely been conducted with less attention on the situation of environment sustainability especially in different economic regimes (expansion and recession). In the current context, the role of income per capita, energy intensity, and urbanization in driving the ecological footprint of Turkey is examined in the framework of Environmental Kuznets Curve (EKC) hypothesis over the period of 1990-2015. Considering the potential evidence of regime switching, we employed the Threshold Autoregressive Model (TAR) method with a regime change threshold of 14.43505 per hectare per capita and found that the EKC hypothesis is valid for all the 4 models. Moreover, eight observations are below the threshold value in the first regime while fifteen observations are equal or higher than the threshold value in the second regime. With a threshold per capita income of 9340.1326 USD, the study found that Turkey begin to experience a decline in environmental degradation resulting from income growth in 2015. However, this desirable outcome was short-lived in 2018 because the per capita income slightly decreases to 9340.1326 USD. In addition, increases in energy intensity and urbanization level hamper environmental sustainability drive of the country. The frequency domain causality test further supports the nexus evidence among the implied variables. By virtue of observation, this study offers that the government should work toward achieving a sustainable growth in order to attain the country's environmental sustainability agenda.

Natural gas consumption-economic output and environmental sustainability target in China: an N-shaped hypothesis inference

On one divide, energy types have been linked with the varying degree of environmental damage. Another perspective argued on the severity of the damaged base on per capita and/or population consumption pattern. As such, this study investigates the nexus of per capita natural gas consumption-carbon dioxide emissions and per capita income-carbon dioxide emissions in the case of the People of the Republic of China. This study objectively expanded to illustrate whether the N-shaped environmental Kuznets curve hypothesis holds in the case of China or not. The employed autoregressive distributed lag bound testing approach incorporated additional explanatory variables (urbanization) within the N-shaped EKC hypothesis over the period 1971-2018. Importantly, the results show an evidence of inverted N-shaped EKC relationship. In addition, the study posits a positive relationship between natural gas consumption and carbon dioxide emissions and between urbanization and carbon dioxide emissions. Thus, the study proposes renewable energy development and decongestion of the urban centers as a means of controlling global warming.

Perspectives of globalization and tourism as drivers of ecological footprint in top 10 destination economies

Beyond the anticipated experience associated with tourism destinations, the United Nations World Tourism Organization (UNWTO) has further tasked (especially the destination countries) on the importance of tourism to achieving the 2030 Sustainable Development Goals (SDGs). From this dimension, this study employed the ecological footprint of the 10 most visited countries (France, Spain, United States, China, Italy, Mexico, United Kingdom, Turkey, Germany, and Thailand) over the period 1995-2016. Specifically, the study employed an econometric approach and found that increase in tourism arrivals and globalization is detrimental to the attainment of sustainable environmental quality in a long term. Precisely, a 1% increase in international arrivals and globalization is responsible for a 0.18 and 0.89% increase in ecological footprint in the long-run. These impacts of tourism activities and globalization are detrimental to the environmental quality of the destination countries. Meanwhile, the real income per capita and biocapacity in the destination countries improve the environmental quality of the panel of destination countries in the long-run. In addition, the study found significant evidence of Granger causality from tourism and real income to ecological footprint without feedback, the globalization-ecological footprint Granger causality nexus is with feedback. Moreover, potentially effective policies for government and other stakeholders especially toward attaining Global goals were proffered in the study.

Environmental aspect of energy transition and urbanization in the OPEC member states

More than any other nations, the crude oil-exporting countries and especially the Organization of the Petroleum Exporting Countries (OPEC) are likely to experience a more difficult energy-transitioning regime because of the economies' high dependence on crude oil revenue. By using the Pooled Mean Group (PMG) Autoregressive Distributed Lag Models (ARDL) approach, this study examines the impact of the energy transition albeit from conventional to clean energy on carbon emissions in 11 members of the OPEC. While engaging the aforementioned objective, the study further examined the validity of the Environmental Kuznets Curve (EKC) hypothesis amidst urbanization drive among the countries. The result from the long-run estimates shows that fossil fuel utilization exerts a positively significant on environmental degradation in the selected countries, while the observed negative impact of renewable energy utilization and urbanization on carbon dioxide emission (CO₂) was insignificant in both the short and long run. The implication is that the current energy transition policy of the OPEC states is not sufficient at driving the states' environmental sustainability agenda. In addition, the EKC was not valid in the panel of the OPEC countries for the period of study, rather a U-shaped relation is established between income level and environmental degradation. Thus, this further posits that there is a setback in the push for environmental quality especially when there is an improvement in economic well-being through income growth in the OPEC states. Moreover, findings from the panel causality test show that there is no causality running from both fossil fuel and renewable energy consumption to the income level among the countries. On the contrary, a uni-directional causality was obtained from income level to renewable energy consumption, while urbanization strongly Granger causes fossil fuel use and CO₂ emissions among the countries. As such, it is concluded that energy conservation policies can be implemented to reduce extreme dependence on fossil fuel use with little or no detrimental consequences, thus positioning the countries for economic prosperity in a sustainable environment.