Environmental quality and the role of economic policy uncertainty, economic complexity, renewable energy, and energy intensity: the case of G7 countries

Relationship among micro-pollutants, economic growth, renewable energy, nanotechnology and ecological foot prints of China: evidence from panel data analysis

An important concern is the availability of clean drinking water, which is an essential need for human survival. This issue arises due to the existence of hazardous micropollutants originating from various emission sources. Nanotechnology aids in the mitigation of micropollutants by assimilating and counteracting their effects, hence diminishing their influence on water and other ecosystems. The study investigates the relationship between nanotechnological progress, the adoption of renewable energy, environmental consequences, and economic growth in China, using the Environmental Kuznets Curve theory as a conceptual framework. The study employs panel cointegration tests to analyze structural breaks from 2000 to 2020. Nanotechnology is expected to reduce environmental degradation and the presence of micro-pollutants by increasing the use of renewable energy and promoting energy conservation. Nanotechnology is crucial for mitigating micro-pollutants and advancing sustainable development in this specific context. However, the literature also highlights the harmful consequences of nanoparticle emissions caused by nanotechnology on human and environmental health for a long duration, requiring more examination. This research is the first empirical inquiry into the relationship between improvements in nanotechnology, the use of renewable energy, economic growth, and ecological effect, all within the context of the Environmental Kuznets Curve theory. The results confirm the successful incorporation of all components with a focus on long-term outcomes. The findings suggest that the EKC hypothesis is relevant in China. In China, advancements in nanotechnology have a moderating effect on environmental degradation. The use of renewable energy sources in China enhances environmental circumstances. Given the offered empirical evidence, it is advisable for the government to have a leading role in the development of innovative nanotechnologies that have low emissions of nanoparticles. By using this approach, it will be possible to encourage the conservation of energy and the use of renewable sources in a more secure way, hence improving the effectiveness of sustainable development initiatives.

Pathway to environmental sustainability: Assessing the role of productive capacity, remittances, and uncertainty in sub-Saharan Africa

Unlike previous studies that have examined the association between different economic development parameters and environmental sustainability, the present study utilised an index of productive capacity to offer an in-depth understanding of the ecological impact of improving a nation's productive resources. It also emphasised the importance of remittances in reducing environmental degradation in uncertain economic and political environments. This study applied the system GMM technique and an advanced panel quantile regression technique to 36 Sub-Saharan Africa (SSA) region countries from 2000 to 2022. The findings showed that improvements in productive capacity might exert pressure on environmental quality, uncertainty, and the inflow of remittances, which tended to have a positive effect, ultimately leading to better environmental outcomes. Furthermore, the study indicated that these variables' impacts differed depending on each country's prevailing ecological conditions. It is, therefore, vital that efforts to achieve sustainable development in the SSA region consider the combined impact of these factors on environmental quality.

Unleashing sustainability in uncertain times: Can we leverage economic complexity, uncertainty, and remittances to combat environmental degradation?

Rapid economic growth and human activities have seriously damaged the environment and hindered the achievement of Sustainable Development Goals (SDGs). Hence, this study aims to explore the impact of economic complexity, uncertainty, and remittance on environmental degradation in 134 countries from 2000 to 2022. In addition, it examines whether uncertainty moderates the relationship between remittance and environmental degradation. Two proxies (ecological footprint and CO2) were used to measure environmental degradation. The analysis was conducted using a cross-sectional dependency test, second-generation unit root test, and panel quantile regression. The results revealed that economic complexity significantly and positively impacted environmental degradation, while uncertainty and remittance significantly and negatively impacted environmental degradation. Furthermore, uncertainty weakened the negative relationship between remittance and environmental degradation. Accordingly, this paper discusses various recommendations and policy implications regarding economic complexity, uncertainty, remittance, and environmental degradation.

Economic complexity, greenfield investments, and energy innovation: policy implications for sustainable development goals in newly industrialised economies

The crucial role of environmental assessment quality has been recognised by environmental and sustainable development goals in addressing climate change challenges. By focusing on the key identifier of environmental assessment, progress can be made towards overcoming climate change issues effectively. The current study considers environmental commitments under COP28 to study the role of economic complexity, greenfield investments, and energy innovation in environmental degradation in newly industrialised economies from 1995 to 2021. We employ novel panel estimations from CS-ARDL, CS-DL, AMG, and CCEMG to confirm that economic growth and greenfield investments degrade environmental quality. On the other hand, energy innovation and urbanisation improve environmental sustainability. Lastly, we confirm the EKC hypothesis for economic complexity as well. Given the reported empirical findings, the study suggests policymakers must focus on economic complexity to transform industrial sectors' economic potential. Furthermore, foreign investment projects must be linked with environmental goals to increase renewable energy capacity.

Does green investment affect environment pollution: Evidence from asymmetric ARDL approach?

Pollution in the environment is today the biggest issue facing the globe and the main factor in the development of many fatal diseases. The main objective of the study to investigate green investments, economic growth and financial development on environmental pollution in the G-7 countries. This study used annual penal data from 1997 to 2021. The panel NARDL (Non-linear autoregressive distributed lag) results affirm that the positive change of green investment and negative shock in green investment have a significant and positive association with environment pollution in G-7 nations. Our findings provide more evidence for the long-term asymmetry between financial development and environmental performance. However, the findings confirm that a positive modification in financial development has a positive and significant effect on environment pollution. Whereas negative shock in financial development is negative and insignificant relationship with environment pollution. Moreover, the outcomes of the study reveal that both positive shock in gross domestic product growth and negative shock of economic growth have a significant and positive link with environment pollution in G-7 countries. According to the findings, by lowering carbon dioxide emissions, green investments reduced environmental pollution in the G-7 nations over the long and short term. Moreover, it is an innovative research effort that provides light on the connection between green investments, financial development, and the environment while making mention to the EKC in G-7 countries. After all these, our recommendation is to increases green investment expenditures to reduce environmental pollution in the G-7 nations based on our findings. Additionally, one important way for the nation to achieve its sustainable development goals is to improve advancements in the financial sector.

The impact of technological innovations on the environmental Kuznets curve: evidence from EU-27

The EKC hypothesis expresses the inverted U-shaped relationship between per capita income and environmental quality. In the literature, the role of technological innovations and income inequality on pollution is a relatively recent discussion in the studies testing the EKC hypothesis. The aim of this paper is to investigate the impact of technological innovations, income inequality, exports, urbanization, and growth on CO2 emissions in EU-27. In addition, while investigating this relationship, exports and urbanization are also considered and panel vector autoregression (PVAR) analysis is applied for the 2005-2019 period. According to the coefficient estimation results, while income inequality, exports, and urbanization increase pollution, technological innovations contribute to environmental quality. Also, the results demonstrated that the EKC hypothesis is invalid in these countries and there is a U-shaped relationship between growth and emissions. The causality test results revealed the presence of unidirectional causality running from all explanatory variables to CO2 emissions. Moreover, impulse-response graphs demonstrated that the reply of emissions to the shocks in the explanatory variables is similar to the long-run coefficient results. In conclusion, all available empirical evidence for this relationship highlights that income inequality and technological innovations should be considered in policy-making processes to ensure environmental quality in EU-27 countries.

Quantile connectedness between the climate policy and economic uncertainty: Evidence from the G7 countries

In this study, we investigate the transmission mechanism between climate policy uncertainty (CPU) and economic policy uncertainty (EPU) in the G7 countries. To account for different conditions, we use a quantile-based VAR (Q-VAR) model over the period between 2000 and 2021. Our results show high connectedness between the CPU and the EPU of G7 countries, particularly at extreme quantile orders. On the other hand, the spillover effects between climate and economic policy uncertainty differ depending on the distributional levels of the uncertainty indices. The CPU is a net receiver of uncertainty shocks, while for almost all countries, the EPU acts as a net receiver or emitter, depending on the economic situation. During times of high or low economic uncertainty, the EPU of all G7 countries is strongly affected by shocks originating from the CPU. Moreover, the results indicate that the dynamic spillover patterns between EPU and CPU vary over time, responding to different economic events and financial crises. These results call for policymakers and governments to urgently integrate climate considerations into economic planning, fiscal policies, and regulatory frameworks to promote sustainable economic growth and mitigate the impacts of climate change.

Investigating the fishing grounds load capacity curve in G7 nations: Evaluating the influence of human capital and renewable energy use

This paper introduces a novel approach to explore marine ecosystem by examining the Fishing Grounds Load Capacity Curve (FGLCC) hypothesis. The study investigates the impact of income on the marine condition in G7 nations from 1970 to 2019 by exploring the U-shaped relationship between income and the Fishing Grounds Load Capacity Factor (FGLCF). This research diverges from previous studies focused solely on the demand side through fishing footprints, as it considers the neglected aspect of the marine supply side. Furthermore, it explores the influence of renewable energies and human capital as indicators inversely related to non-renewable energy use and population on the marine condition. The findings reveal the U-shaped FGLCC hypothesis. Additionally, the results demonstrate that renewable energies and human capital have a positive impact on the marine ecosystem. These outcomes provide valuable insights for decision-makers, enabling them to identify key variables that contribute to the preservation of marine diversity.

Renewable energy policy and deployment of renewable energy technologies: The role of resource curse

Due to the increasing emission of greenhouse gases and global warming, the development of renewable energy has become very important. The availability of fossil fuels and the low cost of their extraction compared to renewable energy projects reduce the motivation of countries, especially countries that have abundant natural resources, to develop this technology. Renewable energy deployment has become crucial in response to rising greenhouse gas emissions and global warming. Policies supporting renewable energy play a significant role in this. This study examines the effect of such policies on the deployment of renewable energy technologies, considering the role of natural resources. Two groups of countries were analysed: 20 oil developed countries and 20 oil developing countries. Given the availability of data and the achievement of balanced panels to evaluate short-term and long-term relationships between variables, in current research Data from 2010 to 2020 was used, and various panel data estimators such as Feasible Generalized Least Squares and Generalized Method of Moments were employed. The Quantile estimator was also used to assess the accuracy of the results. The findings suggest that renewable energy policies consistently lead to increased deployment of renewable energy technologies, regardless of a country's group. Of course, this positive effect is different according to the level of development in countries. Due to the higher efficiency of renewable energy policy, developed oil countries have more capacity to support renewable energy projects than oil developing countries. The abundance of natural resources in oil developed countries did not negatively impact renewable energy capacity, but in oil developing countries, the "resource curse" hindered the development of installed renewable energy.

Environmental sustainability through aggregate demand and knowledge economy interaction-a case of very high-HDI countries

The magnitude of the economic activities is immense in very high-Human Development Index (HDI) countries, leading to environmental degradation, a crucial problem. This study is aimed at testing aggregate demand's role in the environmental Kuznets curve (EKC) perspective and explores the role of four pillars of the knowledge economy, viz., technology, innovations, education, and institutions, as proposed by World Bank, in maintaining sustainable development of environmental quality in these countries. The analysis covers the period ranging from 1995 to 2022. The departure of normality of the variables provides a solid base for panel quantile regression (PQR). Unlike ordinary least squares (OLS) regression, which estimates the conditional mean of the dependent variable, PQR estimates the conditional quantiles. The estimated results using PQR confirm both U and inverted U-shaped aggregate demand-based EKC. In fact, these knowledge pillars in the model determine the shape of EKC. Results also reveal that two knowledge pillars, i.e., technology and innovations, are responsible for significantly reducing carbon emissions. In comparison, education and institutions are responsible for expanding carbon emissions. As a moderator, all knowledge pillars except institutions are shifting the EKC downward. The key lessons from these findings are that technology and innovation can reduce carbon emissions, while education and institutions may have a mixed impact. The relationship between knowledge pillars and emissions may be moderated by other factors, underscoring the need for further research. Moreover, urbanization, energy intensity, financial development, and trade openness significantly contribute to environmental deterioration.

Environmental reverberations of geopolitical risk and economic policy uncertainty resulting from the Russia-Ukraine conflict: A wavelet based approach for sectoral CO2 emissions

After the COVID-19 pandemic, Russia invaded Ukraine in February 2022, and a natural gas crisis between the European Union (EU) and Russia has begun. These events have negatively affected humanity and resulted in economic and environmental consequences. Against this background, this study examines the impact of geopolitical risk (GPR) and economic policy uncertainty (EPU) caused by the Russia-Ukraine conflict, on sectoral carbon dioxide (CO₂) emissions. To this end, the study analyzes data from January 1997 to October 2022 by using wavelet transform coherence (WTC) and time-varying wavelet causality test (TVWCT) approaches. The WTC results show that GPR and EPU reduce CO₂ emissions in the residential, commercial, industrial, and electricity sectors, while GPR increases CO₂ emissions in the transportation sector during the period from January 2019 to October 2022, which includes Russia-Ukraine conflict. The WTC analysis also indicates that the reduction in CO₂ emissions provided by the EPU is higher than that of the GPR for several periods. According to the TVWCT, there are causal impacts of the GPR and the EPU on sectoral CO₂ emissions, but the timing of the causal impacts differs between the raw and decomposed data. The results suggest that the EPU has a larger impact on reducing sectoral CO₂ emissions during the Ukraine-Russia crisis and that production disruptions due to uncertainty have the greatest impact on reducing CO₂ emissions in the electric power and transportation sectors.

Investigating the nexus between trade policy uncertainty and environmental quality in the USA: empirical evidence from aggregate and disaggregate level analysis

Worldwide, environmental sustainability is a hot topic, particularly in industrialized countries due to their higher emission intensity. Environmental conservation and equitable economic growth have been prioritized in economic debate and policy development. Over the past three decades, the USA's emissions of carbon dioxide (CO₂e) have risen exponentially, as trade policy uncertainty (TPU). In this circumstance, this paper aims to contribute to the existing literature by exploring the effect of TPU on environmental quality by controlling the energy consumption, economic growth, and population in the USA over the period 1985M1 to 2022M3 employing the augmented ARDL and NARDL procedures in the presence of structural breaks. From our analysis, the results revealed that TPU affects negatively CO₂e in the residential sector, and negative changes in TPU positively affect CO₂e in the commercial sector both in the long and short run. On the other side, the outcomes show that energy consumption is a crucial key determinant factor in environmental degradation at the aggregate level and in all sectors. Furthermore, our findings clarify that economic growth upsurges the CO₂e at the aggregate level precisely in the industrial and residential sectors. Juxtaposing, in the long run, the results indicate that population growth could make additional pressure on environmental quality at the aggregate level, especially in commercial, power generation, and residential sectors. Accordingly, it is clear from our results that the regulations put in place to encourage Americans to buy locally created goods instead of those imported, especially in light of the high levels of TPU, maybe the best option to decrease the long-term impact of international trade on the environment to achieve sustainable development goals (SDGs).

Impact of economic policy uncertainty, geopolitical risk, and economic complexity on carbon emissions and ecological footprint: an investigation of the E7 countries

There is a plethora of studies on the energy-consumption-environmental-quality nexus. Nevertheless, empirical research on the impact of global uncertainties on environmental quality is lacking. This study contributes to the literature by examining the impact of economic policy uncertainty (EPU), geopolitical risk (GPR), and economic complexity on the ecological footprint and carbon emissions of E7 economies for the period 1995-2018. Our empirical results indicate a long-term relationship between economic complexity, EPU, GPR, energy consumption, and two environmental quality indicators, carbon dioxide emissions and ecological footprint. In the long run, a divergence from disequilibrium takes 3 years to return to the equilibrating position. The environmental effects of key determinants are different in terms of direction, magnitude, and time span. Specifically, an inverted U-shape describes the relationship between economic complexity and environmental degradation in the long-term only, which confirms the environmental Kuznets curve (EKC) hypothesis. The environmental effects of EPU and GPR are harmful in the short run but prove to be beneficial in the long run. Higher energy consumption significantly degrades environment quality as expected. Based on these findings, the paper provides several useful suggestions for policymakers in the context of E7 countries.

Is reducing fossil fuel intensity important for environmental management and ensuring ecological efficiency in China?

Since China is a country with high environmental pollution, researchers have intensively studied China's environmental problems using various environmental indicators such as carbon emissions and ecological footprint. Unlike previous literature, this study analyzes the effects of economic growth, globalization, foreign direct investment, and fossil energy intensity on ecological efficiency in China. As an innovation to the literature, the study examines the Chinese ecosystem simultaneously with its economic and environmental aspects by focusing on ecological efficiency. To this end, the study applies dynamic autoregressive distributed lag (DARDL) simulations and kernel-based regularized least squares (KRLS) methods for the period from 1990 to 2018. The results of the DARDL simulations show that globalization, and economic growth enhance ecological efficiency in China. The findings also demonstrate that both foreign direct investment and fossil fuel intensity have a negative impact on environmental quality in China. Based on these results, the study suggests that the Chinese government should adopt policies to channel foreign direct investment into environmentally friendly production, reduce fossil fuel intensity, and improve ecological efficiency by making use of environmentally friendly technologies provided by globalization and economic development.

Are the impacts of renewable energy use on load capacity factors homogeneous for developed and developing nations? Evidence from the G7 and E7 nations

Both developed and underdeveloped economies worldwide are now more concerned than ever in respect of achieving environmental sustainability. Accordingly, the majority of the global economies have ratified several environment-related pacts to facilitate the tackling of global environment-related problems. Although these problems are assumed to be addressed using diverse mechanisms, limiting the use of fossil fuels has often been recognized as the ultimate enabler of environmental sustainability. Against this backdrop, this study aims to assess the environmental impacts associated with higher renewable energy use, controlling for economic growth and population size, in the context of the G7 and E7 countries using data from 1997 to 2018. Moreover, instead of using the traditional environmental quality proxies, this study tries to proxy environmental degradation with the load capacity factor levels of the countries of concern. The long-run associations among the study's variables are confirmed by outcomes generated from the cointegration analysis. Besides, regression analysis highlighted that integrating renewable energy into the energy systems while withdrawing from the use of fossil fuels can help to improve environmental quality by increasing the load capacity factor levels. In contrast, economic growth and population size expansion are evidenced to impose environmental quality-dampening impacts by reducing the load capacity factor levels. However, the findings, in the majority of the cases, are seen to differ across the groups of the G7 and E7 countries, especially in terms of the variations in the magnitudes of marginal environmental effects over the short and long run. Lastly, the causality analysis confirms the directions of the causal relationships among the variables of concern. Based on these results, a couple of policy interventions are recommended for improving environmental quality in the G7 and E7 countries.

Exploring the impacts of economic policy uncertainty, natural resources, and energy structure on ecological footprints: evidence from G-10 nations

The role of energy and natural resources rent has been studied in the literature but very few research works investigated the impacts of economic policy uncertainty and energy structure on ecological footprints (EFs) in the group of ten G-10 countries. Therefore, this research is designed to probe the impacts of economic policy uncertainty (EP), natural resources rent, energy structure, economic growth, and total factor productivity on EF. The annual data for 1995-2018 is analyzed by adopting second-generation methods. The empirical results from the CS-ARDL unveiled that EP is significantly and positively related to EF, indicating that EP is not environmentally friendly in these nations. A 1% increase in EP contributes to EF by 0.025% in the long run. In addition, the results show that natural resource rents and energy structure positively contribute to mitigating EF by 0.012% and 0.095% respectively, while economic growth increases EF by 0.237%. Based on the empirical results, this work suggests addressing the economic policy uncertainty and economic progress to lower ecological deprivation can be a viable solution to attain sustainable development goals. This work recommends adopting feasible economic policies with sound efforts. For this purpose, the economic sector has to be strong enough with sustainable production. They should ensure the supply of continuous renewable energy to the economic sector.

Investigating the moderating role of economic policy uncertainty in environmental Kuznets curve for South Africa: Evidence from the novel dynamic ARDL simulations approach

South Africa, one of the emerging markets and fast-developing economies in Sub-Saharan Africa recognised for varying world's natural assets on the international market, has recorded significant economic growth in the previous several years. However, aside from the ecological repercussions of energy generation, how economic uncertainties moderate the effects of energy intensity, renewable and non-renewable energy usage, and economic complexity on the environment has largely gone unnoticed. As a result, this paper addresses an important empirical vacuum by exploring the moderating influence of economic policy uncertainty in the environmental Kuznets curve for South Africa from 1960 to 2020. Results from the novel dynamic autoregressive distributed lag simulations framework reveal the following key findings: (i) economic policy uncertainty accelerates environmental degradation in both the short and long run; (ii) economic growth (as measured by the scale effect) increases environmental degradation, whereas the square of economic growth (as measured by the technique effect) slows it down, confirming the presence of the environmental Kuznets curve (EKC) hypothesis; (iii) environmental quality is deteriorated by energy intensity, economic complexity, non-renewable energy usage, and trade openness; (iv) the use of renewable energy and technological innovation increase environmental quality; (v) whereas the moderating effects of economic policy uncertainty on the environmental impacts of energy intensity, renewable and non-renewable energy consumption result in an increase in environmental destruction, its moderating effect on environmental implication of economic complexity plays an important role in improving environmental quality. These findings permit us to draw important policy recommendations for South Africa for improving environmental quality.

The shadow economy-environmental quality nexus in OECD countries: empirical evidence from panel quantile regression

This study examines the heterogenous impact of shadow economy on the ecological footprint. We apply the panel quantile regression to a panel dataset of 32 OECD countries from 1990 to 2015. The estimation results indicate that the shadow economy-ecological footprint nexus follows an inverted U-shaped pattern. Initially, the higher size of the informal economy leads to more ecosystem degradation. When the shadow economy increases to certain thresholds, its environmental impact reverts to benefit. Such threshold changes with the evolution of the ecological footprint. Specifically, it first rises then decreases along with the degradation of the ecosystem. Moreover, the heterogeneous panel causality test reports the one-way directional running from the shadow economy to the ecological footprint in OECD countries. Likewise, environmental effects of other control variables, including trade openness, energy intensity, renewable energy, and income, are also not homogeneous across various levels of the ecological footprint. The significant and heterogeneous relationships between ecological footprint and its determining factors provide insightful implications for governments in tailoring environmental regulations upon different ecological conditions.

Natural resources, population aging, and environmental quality: analyzing the role of green technologies

Depletion of natural resources and population aging are the two most critical challenges for environmental sustainability. However, the research that integrates natural resources and population aging in the same environmental policy framework is still scant. Therefore, this study investigates the linkage between natural resources, population aging, green technologies, and ecological footprint (EF) of G7 countries. In addition, this study also explores the moderating effects of green technologies on the relationship between natural resources and EF. Drawing on the panel times series data from 1970 to 2017, we employ a cross-sectional autoregressive distributed lags (CS-ARDL) model for short- and long-run empirical estimation. Our empirical analysis indicates that natural resource use exacerbates ecological degradation by increasing EF. By contrast, population aging and green technologies present positive ameliorative effects on EF. Interestingly, the interaction effect of green technologies and natural resources indicates that the damage to ecological quality from natural resources can be effectively improved by means of green technologies, thus maintaining environmental sustainability. Furthermore, the results of panel quantile regression show that the effects of population aging and green technologies on the overall ecological footprint distribution in G7 countries are heterogeneous, while the effects of natural resources on the distribution of all conditions of the ecological footprint are positive. In addition, this paper verifies the causal relationship between the variables using the Dumitrescu and Hurlin test. The findings reveal that the relevant changes in all explanatory variables are bilaterally causally associated with EF. Based on these results, this paper provides some feasible policy recommendations.

Do economic policy uncertainty and environment-related technologies help in limiting ecological footprint?

Economic policies related to energy and the environment are found uncertain in developing economies. Renewable energy sources are gradually increasing in energy structure (ES) with the adoption of environment-related technologies (ERT). However, least attention is paid to investigating the nexus of economic policy uncertainty (EPU), ERT, ES, and ecological footprint (EF). Therefore, this study is an effort to examine the EPU, ERT, ES, and interaction of EPU and ERT on EF for BRICS economies under the umbrella of the STIRPAT model. By using the data from 1992 to 2020, findings are estimated through "cross-sectional dependence (CD test); CIPS and CADF unit root test; Westerlund's co-integration; and CS-ARDL, AMG, and CCEMG." Findings unveiled the negative role of EPU on EF. Furthermore, the role of RE and ERT is positive and substantial in decreasing the environmental degradation in BRICS. Therefore, the BRICS economies are suggested to be consistent on economic policies to catch the positive impact of ERT. Findings are robust to the policy implications.

Economic Policy Uncertainty, Social Development, Political Regimes and Environmental Quality

This paper aims to examine the influence of Economic Policy Uncertainty (EPU) on environmental performance, as well as the moderating effect of social development and the political regimes in EPU’s influence on environmental performance. To investigate such essential issues, we conducted Generalized Method of Moments (GMM) estimations by utilizing cross-country data covering 137 countries during the period of 2001–2018, according to the Stochastic Impacts by Regression on Population, Affluence and Technology (STIRPAT) model. Our empirical estimations support that EPU negatively affects environmental performance; this idea was still supported when we conducted an empirical analysis by changing the measurements, employing alternative estimations and constructing new samples. Furthermore, not only would the absolute level of EPU bring worse environmental performance, but so would an increase in EPU. Moreover, higher economic performance, globalization and a high quality of governance can help countries to alleviate the adverse environmental effect of EPU. Additionally, EPU’s negative effect on environmental performance is stronger in right-wing countries, autocracies and non-OECD countries, compared to their counterparts. Our study provides substantial policy implications for governments participating in the international treaties of environmental protection, to mitigate environmental degradation.

Nexus Between Economic Efficiency, Healthcare, and Environmental Expenditures: A Perspective of BRI Countries

Public health and the environment are the most essential pillars, and play a vital role in the economy. In order to better public health, the economic and environmental atmosphere must be stable and clean, respectively. Thus, this paper emphasizes on nexus between economic, public health, and the environment. Therefore, the objective of this paper is whether healthcare and environmental expenditures affect economic efficiency and vice versa. So, this study evaluates the performance of the country's economic efficiency and investigates the effect of healthcare and environmental expenditures for 62 Belt and Road Initiative countries for the period from 1996 to 2020. Suitable input-output variables are employed under the framework of DEA-window and Malmquist Index Productivity, and Stochastic Frontier Analysis (SFA). In addition, this study estimates the relationship between economic efficiency, healthcare, and environmental expenditures by fixed and random effects models. Therefore, the analytical outcomes reveal that countries are economically efficient. On the contrary, SFA estimation concludes that countries are found to be inefficient, because higher variation is exists in efficiency change compared to technological efficiency change and total factor productivity change on average. In addition, it is worth notable that healthcare and environmental expenditures improve the country's economic efficiency. Furthermore, public health is also influenced by economic efficiency. Thus, this study suggests that countries should better utilize given resources and invest a specific portion of national income in order to improve economic efficiency.

Impact of Economic Policy Uncertainty on Carbon Emissions: Evidence from 137 Multinational Countries

With growing economic policy uncertainty (EPU) and the importance of protecting the natural environment worldwide, the relationship between EPU and carbon emissions should be investigated further. However, conclusions in the existing literature on the relationship between EPU and carbon emission are inconclusive. This paper aims to examine the influence of EPU on carbon emissions according to the Stochastic Impacts by Regression on Population, Affluence and Technology (STIRPAT) model. To investigate such essential issues, we conduct GMM estimations by utilizing cross-country data covering 137 countries during the period 1970–2018, obtained from World Bank and OECD statistics. Our empirical estimations support that EPU would bring about more carbon emissions, while we conduct empirical analysis by changing the system of measurement, employing alternative estimation and constructing new samples. Our study provides substantial policy implications for government participation in international treaties on environmental protection to mitigate environmental degradation.