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Airborne and spaceborne hyperspectral imaging techniques are topics of great interest in the remote sensing field due to their ability to provide rich spatial and spectral information, which are paramount for a better characterization of the Earth's surface and atmosphere. This paper provides a comprehensive review of the current state-of-the-art in the applications of airborne and spaceborne hyperspectral imaging for atmospheric research. Main hyperspectral imaging systems, data analysis methods and their applications in some atmosphere research areas, including the estimation of aerosol and water vapor content for a deeper understanding of atmospheric phenomena, cloud characterization for better prediction of weather phenomena, and gas emissions detection for air quality control, were discussed. Many studies have shown very promising results, but as hyperspectral imaging is in a continuous dynamic, there are several challenges that need to be addressed in future studies so that it can become one of the most important tools for atmosphere research. The answer to some questions on this topic is provided and directions for future research are outlined. [ABSTRACT FROM AUTHOR]

The Iran-Saudi Arabia conflict is an ongoing struggle for influence in the region that has created uncertainty, affected oil prices and regional economics. This paper uses wavelet analysis to examine the frequency and time-varying co-movement and casual nexus between petroleum prices (OP) and financial liquidness (MS) with and without geopolitical risk (GPR). The aim is to test the validity of the monetary equilibrium model from 1988 to 2019. The model is supported by the findings, as both short and medium-term association is found between OP and MS at high frequencies in the presence of GPR. We find a medium-term association between OP and MS in the absence of GPR. The paper's overall conclusion suggests that GPR affects OP and OP, in turn, impact MS. Diversifying economic activities to minimize oil dependency, which is sensitive to external shocks, is suggested as a mitigation solution. [ABSTRACT FROM AUTHOR]

Electric power shortfalls driven by inadequate generation, electrification, and lack of clarity on the planning side have worsened Pakistan's power crises that deformed economic growth. This study focuses on the estimation of the electricity supply and demand in the China-Pakistan Economic Corridor (CPEC) perspective and on the main reasons that motivate a transition to green resources. This paper estimated the demand-supply gap (1990–2015) and forecasted it (2016–2035), including CPEC projects using the System Dynamics model. The results show that the power demand will be met by 2021, fact highlighted also by a battery of robustness tests. We find that the CPEC efforts will increase energy growth from 4.5% (1990–2015) to 14.6% (2016–2035). The capacity growth will increase from 4.9% to 12.3% during 2016–2035. Moreover, the current renewable energy production and investment (Wind & Solar Power) will not help achieve policy targets. A total investment of $4806.69 million is required to meet policy targets, while a value of $57,683 million is needed for a complete conversion to green energy. The study highlights the challenges on the green energy path and discusses policies needed to overcome these problems. [ABSTRACT FROM AUTHOR]

Venezuela's oil-dependent economy is severely affected by geopolitical instability, causing hyperinflation and devaluation of the national currency. Therefore, this study intends to examine the nexus among geopolitics, exchange rate, and oil prices by employing the Wavelet analysis for a sample ranging from 2008 to 2019. The results reveal that oil prices and exchange rates have a bidirectional causal relation from 2017 to 2019. Similarly, geopolitics and oil prices cause each other from 2017 to 2019. A medium-run co-movement between geopolitical risk and exchange rates is observed from 2015 to 2019. We notice that oil prices and exchange rates exhibit a causal relation from 2008 to 2011 and from 2018 to 2019. The results support the theoretical model and are in line with the actual dynamics of the economy. Based on our results, we conjecture that Venezuela has to reduce its oil dependence since it is susceptible to geopolitical risk, avoid regional conflicts, and manage exchange rates to achieve sustainable growth. [ABSTRACT FROM AUTHOR]

This paper proposes a novel cooperative game network DEA model for evaluating marine circular economy (MCE) performance. The proposed model considers the bidirectional link between the economic production (EP) and environmental treatment (ET) subsystems within the MCE system. Then, the cooperative game strategy between subsystems is modeled by maximizing the factor inefficiency both of subsystems into the model's measurement from a centralized control perspective. The evaluation results of China's regional MCE performances over 2006–2015 show that while most coastal areas have a better efficiency score for the EP system, their performance of the ET system is worse and leads to poor MCE performances. In addition, converge analysis indicates that there exists β converge of efficiency difference across coastal regions in the long term. Furthermore, the efficiency decomposition reveals that many inefficient environmental treatment inputs contribute to the worse performance of the ET system. Based on the above findings, several specific policy implications for the existing problems are provided to promote China's MCE. • A novel two-stage game DEA is proposed for evaluating MCE performance. • Regional disparity and stage characteristic of MCE in China are explored. • Convergence analysis of efficiency change are provided. • Factor efficiency is given as the determinant of system performance. • Policy suggestions are proposed for promoting marine circular economy. [ABSTRACT FROM AUTHOR]

Energy and carbon emission performance evaluation is a focus topic in the field of environmental protection and energy utilization. However, the current studies are not high in identifying economic output inefficiency and neglect to control target energy carbon emission intensity (ECI), which may cause evaluation bias. Hence, this paper presents a constrained performance index measure (CPIM) model to solve the issues. The proposed model takes the performance index measure and can identify more numbers of positive economic output inefficiency compared to the directional distance function (DDF) model. Besides, the ECI constraint is presented and imposed into the proposed model to restrict the target ECI of decision making units. The numerical example from China's provincial dataset demonstrates and confirms the validity and merit of the proposed model through the measure and constraint comparison among different models. Then, it is found that most provinces exist certain economic output inefficiency and the center regions have a worst score of energy carbon emission performance index due to the rapid development of their secondary industry by using the proposed model. Several valuable modeling directions and questions related to performance index measure and energy pollution emission constraints are provided for future research. • We propose a constrained performance index measure (CPIM) model. • The CPIM model can identify more economic output inefficiency than the DDF model. • The CPIM model can restrict target energy carbon emission intensity of DMUs. • The numerical example demonstrates the usefulness of the proposed approach. [ABSTRACT FROM AUTHOR]

The cross efficiency (CE) model has been accepted as an alternative approach for evaluating carbon emission efficiency in data envelopment analysis (DEA). However, the current studies can't examine the time effect of economic and energy inputs on regional productivity. This paper proposes a novel method combing CE model with Malmquist productivity index (CE-MPI) to discover a dynamic change of carbon emission efficiencies of China's 30 provinces. The results indicate that Eastern Zone is the most advanced in carbon emission efficiency as well as productivity capacity but the efficiency gap between Inter-mediate and Western Zone is less than 5.7 percent point. The technology progress drives the improvement of the CE-MPI. But the efficiency change pulls down the level of productivity for most zones. Based on the efficiency change and the technical change, China's 30 provinces are divided into four classification and given different recommendations for improving carbon emission efficiency. [ABSTRACT FROM AUTHOR]