Haze Management Research Articles

Haze Management Competition and Industrial Green Transformation

To clarify the relationship between haze management competition and industrial green transformation, this paper is based on the theoretical perspectives of local government competition and environmental federalism, the specific form of haze governance competition is analyzed by applying the two-region spatial Durbin model, and then the impact of haze governance competition on industrial green transformation and its transmission mechanism is explored by constructing a spatial panel linkage model and adopting the generalized spatial three-stage least squares method. The empirical results show that, with the profound changes in the performance appraisal system since the 18th National Congress, the interaction of environmental governance strategies between geographically adjacent provinces is imitative. In contrast, that which is between economically adjacent provinces is a “race to the top”, and haze governance is conducive to promoting the development of industrial green transformation. Further research found that the competition of haze governance is heterogeneous, and smog control in the eastern region contributes to the green transformation of local industries, while smog control in the central and western regions inhibits their industrial green transformation, and haze governance mainly enhances industrial green transformation through the innovation compensation effect, the human capital effect, and the industrial structure optimization effect. Therefore, the central government should carry out overall planning for the industry, and local governments should strengthen the joint prevention and control of haze and promote technological innovation, to improve environmental quality and realize high-quality economic development.

Simulating the effect of haze management using system dynamics: a case study of Beijing

Haze is a pollution phenomenon that has become increasingly frequent in recent years, primarily composed of SO2, NOx, and particulate matter. Since the “PM2.5 Crisis” in 2013, the Beijing-Tianjin-Hebei region has been plagued by haze. After a series of high-intensity management activities, the air quality in Beijing has continued to improve. To investigate the effectiveness of the haze control measures in Beijing, a dynamic management model was constructed using the system dynamics approach and implemented using Stella software. The model is simulated and evaluated the contribution to different governance strategies (increasing investment in science and technology innovation, reducing motor vehicle ownership, reducing coal consumption, and a combination policy) to reduce haze in Beijing from 2010 to 2025. The validity and robustness of the model were verified through model testing and validation. The simulation results showed that: (1) the combination policy has the most significant effect on reducing energy consumption and pollution emissions, which would reduce energy consumption by 38.93 million tons and pollution emissions by 128.33 thousand tons in 2025, (2) among the single treatment measures, reducing industrial coal consumption is the most effective measure to reducing haze, (3) it is necessary to strengthen the joint prevention and control of the Beijing-Tianjin-Hebei region in the future to promote the sustainable development of the regional environment.

Urban innovation, heterogeneous environmental regulations and haze reduction effects–evidence from pilot policies of innovative cities

Innovation-driven development strategies have injected new momentum into haze management. In addition to its core innovation-driven role, innovative city pilot policy is significant for environmental enhancement and should not be overlooked. To assess the performance of the pilot policy in decreasing haze, a multiperiod double difference model was employed, and a spatial econometric model was used to empirically examine the potential spatial spillover effect of haze management as a regional synergistic concept between 2006 and 2020. Panel data from 282 prefecture-level cities were selected. To investigate and empirically examine the territorial spillover effect of haze reduction as a regional synergistic notion, a spatial econometric model was applied. Based on the study, the pilot construction significantly reduced haze pollution. In China’s eastern and central regions, small cities, and newer industrial bases, the inhibitory effect of pilot policies on haze pollution was more pronounced, according to heterogeneity analysis. Moreover, analysis of the heterogeneous environmental regulations revealed that the enforcement of policies would increase the sense of urgency of local governments, strengthen the concern and responsibility of the government for the environment, and further awaken the public’s concern for the environment, in addition to forcing enterprises to practice clean and sustainable production, thus achieving the effect of accelerated haze reduction. From the spatial perspective, innovative pilot cities have certain spatial spillover effects and thus can increase the effects of policy for neighboring regions, similar economic regions and local transportation regions.

PM2.5 Inversion Based on XGBoost And LightGBM Integrated Models

Accurate inversion of PM2.5 concentration is crucial for haze management. Currently commonly used inversion methods cannot accurately invert the concentration in non-site areas, so this paper proposes a PM2.5 concentration inversion method based on an integrated learning model. The method utilises the Top Atmospheric Reflectance (TOAR), observation angle and meteorological element data as input features, and screens the important features by Random Forest, and constructs an integrated inversion model using XGBoost and LightGBM. The results show that the model built by TOAR improves R2 by 2.9% and reduces RMSE and MAE by 2.67 and 1.45, respectively, compared with the AOD-based model, and our model has an inversion accuracy of 0.95, which is better than other models. We used the model to estimate and analyse the historical PM2.5 concentration changes at Huaihe station in Tianjin, China, and the results were consistent with the trend of the actual PM2.5 concentration distribution, and it is clear that the proposed model has a high inversion accuracy.

Innovating from the ground up: the impact of key technological advancements on collaborative carbon and haze governance.

Strengthening the synergistic management of carbon and haze is an important means to realize China's "carbon peaking and carbon neutrality goals" and green development. In this paper, the entropy method is used to measure the key core technology innovation level of 30 provinces in China from 2011 to 2021, and the fixed-effect model is used to empirically test the impact of key core technology innovation on carbon haze synergistic governance and the internal mechanism. The study found that (1) key core technological innovation helps to promote carbon haze synergistic governance. (2) The mechanism test shows that key core technology innovation promotes the synergistic management of carbon haze by improving the clean energy structure. (3) The moderating effect shows that both market incentives and government environmental regulations will strengthen the positive relationship between key core technology innovation and carbon haze synergistic governance. The main contribution of this paper is to reveal the influence mechanism of key core technology innovation on carbon haze synergistic governance, and also to provide theoretical basis for the mechanism and law of carbon haze synergistic governance.

Enhancing urban ecological resilience through integrated green technology progress: evidence from Chinese cities.

The effective resolution of environmental pollution caused by carbon haze through coordinated progress in green technology and urban ecological resilience is a crucial approach towards promoting sustainable development in Chinese cities. In this study, panel data from 281 cities in China from 2007 to 2019 were analyzed using the entropy method and the coupling coordination degree model to determine the coupling coordination degree between green technology progress and urban ecological resilience. The coordinated influence model and threshold model were applied to investigate coupled coordination types and influencing factors. Results indicate that green technology progress levels have shown an upward trend with increasing volatility from east to west and decreasing volatility with urban scale expansion. Ecological resilience levels have also steadily increased, albeit at a reduced rate. The coupling coordination degree of green technology progress and urban ecological resilience has evolved overall from low to high levels; however, the coupling coordination type has regressed to some extent, with most regions exhibiting lagging green technological progress. Pressure resilience has a positive impact on the coupling coordination degree, while state resilience and response resilience have a negative impact. Green technology progress has a dual threshold effect on the coupling coordination degree. By exploring the coupling and coordination mechanism between green technology progress and urban ecological resilience, this study not only facilitates collaborative management of pollutants and greenhouse gases in cities but also provides a comprehensive reference for the construction of an institutional system for collaborative carbon and haze management.

Management of Corneal Haze After Photorefractive Keratectomy.

Photorefractive keratectomy (PRK) is a safe and popular corneal surgery performed worldwide. Nevertheless, there is potential risk of corneal haze development after surgery. Proper management of post PRK haze is important for good visual outcome. We performed a comprehensive review of the literature on the various risk factors and treatments for PRK haze, searching the PubMed, Google Scholar, SCOPUS, ScienceDirect, and Embase databases using relevant search terms. All articles in English from August 1989 through April 2023 were reviewed for this study, among which 102 articles were chosen to be included in the study. Depending on the characteristics of and examination findings on post PRK haze, different management options may be preferred. In the proposed framework, management of PRK haze should include a full workup that includes patient's subjective complaints and loss of vision as well as visual acuity, biomicroscopy, anterior segment optical coherence tomography, epithelial mapping, and Scheimpflug densitometry. Topical steroid treatment for haze should be stratified based on early- or late-onset haze. Mechanical debridement or superficial phototherapeutic keratectomy (PTK) may be used to treat superficial corneal haze. Deep PTK and/or PRK can be used to treat deep corneal haze. Mitomycin-C and topical steroids are prophylactic post-surgery agents to prevent recurrence of haze.

The use of preservative‐free hydrocortisone in the postoperative treatment regimen after trans‐PRK

AbstractPurpose: The purpose of this study was to exhibit the advantages of preservative‐free hydrocortisone in the postoperative treatment regimen of transepithelial photorefractive keratectomy (Trans‐PRK) for the promotion of epithelization and minimalization of early haze appearance.Methods: In this prospective, randomized controlled study, 40 patients who had undergone trans‐PRK were divided into two equal groups, the first group received hydrocortisone (Softacort®, Laboratoires Thea) 2 drops 4 times daily for 7 days and the control group received no complementary medication. Both groups were given: artificial tears 2 drops hourly for 7 days, then administered every 2 h for 21 days and tapered till 3 months post‐operation, antibiotic drops (quinolone) 4 times daily and autologous serum hourly for 7 days, and a bandage contact lens till complete epithelization of the surgical wound. Patients were monitored daily to determine the time of a complete epithelization and then on day 15 and 30 to assess any signs of early‐onset haze and visual acuity. Scheimpflug topography and anterior segment OCT were performed on day 15 and 30 as well as IOP tonometry.Results: The results showed a significant decrease in recovery days in patients treated with hydrocortisone compared to the control group (p < 0.0006) which was associated with a higher rate of early‐onset haze. Both groups had satisfactory visual acuity and no significant differences in their IOP were observed.Conclusions: In conclusion, the use of hydrocortisone sodium phosphate drops (Softacort®) has been shown to be efficient in corneal epithelization and haze management and safe in patients after trans‐PRK.

The monitoring of the speed of re‐epithelization after refractive surgery performed with the method of Trans‐PRK, with the use of hydrocortisone sodium phosphate (Softacort)”

AbstractPurpose: To exhibit the advantages of preservative‐free hydrocortisone in the postoperative treatment regimen of transepithelial photorefractive keratectomy (Trans‐PRK) for the promotion of epithelization and minimalization of early haze appearance.Methods: In this prospective, randomized controlled study, 40 patients who had undergone trans‐PRK were divided into two equal groups, the first group received hydrocortisone (Softacort®, Laboratoires Thea) 2 drops 4 times daily for 7 days and the control group received no complementary medication. Both groups were given: artificial tears 2 drops hourly for 7 days, then administered every 2 h for 21 days and tapered till 3 months post‐operation, antibiotic drops (quinolone) 4 times daily and autologous serum hourly for 7 days, and a bandage contact lens till complete epithelization of the surgical wound. Patients were monitored daily to determine the time of a complete epithelization and then on day 15 and 30 to assess any signs of early‐onset haze and visual acuity. Scheimpflug topography and anterior segment OCT were performed on day 15 and 30 as well as IOP tonometry.Results: The results showed a significant decrease in recovery days in patients treated with hydrocortisone compared to the control group (p < 0.0006) which was associated with a higher rate of early‐onset haze presentation. Both groups had satisfactory visual acuity and no significant differences in their IOP were observed.Conclusions: The use of hydrocortisone sodium phosphate drops (Softacort®) has been shown to be efficient in corneal epithelization and haze management and safe in patients after trans‐PRK.

Does the growth of the digital economy boost the efficiency of synergistic carbon-haze governance? evidence from China

As global urbanization continues to accelerate, so does the amount of harm to the natural ecological environment caused by excessive resource extraction. In several Chinese cities, haze and excessive greenhouse gas emissions have become crucial to the development of an ecological society. To break the previous energy-intensive development model, the data element has emerged as a key driver of the new cycle of high-quality development. Therefore, additional investigation into the synergistic influence of the digital economy as a new factor on air pollution and CO2 emissions is warranted. This study examines the effects, spatial effects, and transmission mechanisms of the digital economy on the synergistic control of carbon and haze using panel data from 30 provinces in China from 2013 to 2019. The study concludes that the digital economy has an overall significant inhibiting effect on carbon dioxide emissions and haze pollution levels (the regression coefficients are -1.090 and -0.714 respectively), a significant driving effect on the efficiency of synergistic carbon and haze management, a spatial spillover effect, and a positive effect on neighboring regions (the regression coefficient is more than 0.239). By region, the digital economy in the eastern region has a greater impact on the effectiveness of carbon and haze management, whereas the digital economy in the western region has a greater impact on CO2 emission reduction, and the digital economy in the central region has an effect that is more consistent with the overall situation. Moreover, the digital economy may successfully encourage technical innovation, which in turn supports synergistic carbon and haze governance, and technological innovation plays a very important mediating role in this transmission mechanism, a finding that is resilient to geographical interaction effects. Consequently, relevant policy recommendations are presented.

Management of corneal haze and edema post-PRK

Introduction: To present the potential use of serum tears, corneal crosslinking, and phototherapeutic keratectomy in the management of corneal haze and edema post-photorefractive keratectomy (PRK). Patient and Clinical Findings: A patient who underwent PRK and subsequently developed corneal haze and edema was treated using conservative management to achieve moderate improvement. Diagnosis, Intervention, and Outcomes: The combination of serum tears, corneal crosslinking, and phototherapeutic keratectomy was used to treat corneal haze and edema, helping the patient achieve an uncorrected visual acuity of 20/20 in the last follow-up. Conclusions: The use of serum tears, corneal crosslinking, and phototherapeutic keratectomy may provide an additional therapeutic option in the treatment of corneal haze and edema that develops post-PRK.

Can Green Technological Innovation Reduce Hazardous Air Pollutants?-An Empirical Test Based on 283 Cities in China.

Based on the panel data of 283 cities in China from 2009 to 2018, this paper analyzes the effect of urban green scientific and technological innovation enhancement on hazardous air pollutants using the GS2SLS method, which simultaneously controls for model endogeneity and spatial spillover effects and reveals the transmission mechanism of urban green scientific and technological innovation level. It was found that (1) There is a significant spatial spillover effect of hazardous air pollutants between regions, both in China as a whole and in the eastern, central, and western parts of the country, and the spatial spillover effect of hazardous air pollutants is significantly greater in the eastern and central parts of China than in the western parts. (2) Green technological innovation has a significant inhibitory effect on hazardous air pollutants in cities in eastern and central China. An extended study found that the improvement in green technology levels in innovative cities has a better effect on controlling hazardous air pollutants than in non-innovative cities. (3) The energy- saving and green economy effects have a mediating influence on the effect of green technological innovation on hazardous air pollutants in cities, and the simultaneous occurrence of these two effects in green technological innovation serves to enhance the transmission of hazardous air pollutants in order to facilitate the long-term management of haze.

Haze management: is urban public transportation priority effective?

Public transportation is often considered as a green travel mode to alleviate the negative externalities such as traffic congestion and haze pollution generated from transport. However, is prioritizing urban public transportation actually conducive to haze emission reduction? In this study, considering special emphasis on the cumulative effect of haze, a dynamic panel model is constructed to analyze and quantify the impact of public transportation on haze pollution by using the data of 284 cities in China, and the heterogeneity of the impact in cities with different pollution levels is examined. Several interesting findings are derived from the empirical results. First, the development of urban public transportation can significantly alleviate urban haze pollution. Second, the haze reduction effect of public transportation in cities with different pollution levels is non-universal. Comparatively speaking, the haze reduction effect of public transportation in lightly polluted cities is more evident than that in heavily polluted cities. Therefore, in order to reduce haze pollution in a more effective manner, China should continue to promote urban public transportation priority strategy. Moreover, the government should also formulate differentiated traffic development strategies to effectively alleviate the urban traffic burdens.

Integrated highland wildfire, smoke, and haze management in the Upper Indochina region

Fire has long been used in Southeast Asia for the purposes of cooking, protection, and warmth. However, climate change and economic pressure have modified the life of locals, including fire practices in daily life and other fire uses. The land use of forest cover in highland area (mostly deciduous forest) has shifted to cultivation, with the application of slash-and-burn techniques. This results in frequent unplanned fires causing pollution in the form of smoke and haze. A zero-burn policy has been implemented to tackle this problem but such a policy may not be appropriate as people still need fire as a basic tool for agriculture land preparation. Moreover, the deciduous forest is a fire-dependent ecosystem to maintain its ecosystem. Frequent burning by local people or excessive government intervention in preventing fires can impact this ecosystem. In the highlands, shifting cultivation has gradually been replaced by rotational agricultural practice with a cycle of 2 to 5 years. However, the fuel load for a 2-year rotation period is only 0.25 tha-1 higher than that of a mixed deciduous forest. New fire risk maps classified according to forest types were produced for Thailand, Lao PDR, and Myanmar. We report that the mixing layer (ML) height in Chiang Mai Province was, on average, 500 m during March, with common occurrence of subsidence inversion resulting in further lowering of air quality during this month. A participatory process to develop a Community Based Fire Management (CBFiM) was undertaken and it was observed that a successful implementation would need a community with a strong leadership.

Two-Phase Group Decision-Aiding System using ELECTRE III Method in Pythagorean Fuzzy Environment

This paper is in the continuation of a well-established line of research in multi-criteria decision making, namely, the development of the basic ELECTRE methodology. In the present study, we make an attempt to enhance the influence of the ELECTRE III method, which was conceived in response to the deficiency that existing variants of the ELECTRE method did not provide a full ordering of the alternatives. ELECTRE III has been recently extended so as to make use of information in the form of intuitionistic fuzzy sets. Although this enhancement has been acclaimed by many scholars, it is nonetheless true that further progresses can be made in the quest of generality. In this research, we develop a two-phase Pythagorean fuzzy version of standard ELECTRE III method, called two-phase Pythagorean fuzzy ELECTRE III (PF-ELECTRE III) approach. It takes full advantage of the capabilities of Pythagorean fuzzy sets (PFS); a successful model that generalizes intuitionistic fuzzy sets in a practical and intuitive way. The group decision support system of PF-ELECTRE III first evaluates the performances of the alternatives characterized by Pythagorean fuzzy numbers. The second stage produces a complete ranking of the alternatives from their evaluations in the first phase. We formulate the approach by defining PF indifference threshold, preference threshold and veto threshold functions which provide a more reliable basis to construct outranking relations. The ranking module of the PF-ELECTRE III method is simplified by computing the concordance credibility, discordance credibility and net credibility degrees of each alternative. A diagrammatic representation of the group decision-supporting system is presented to justify the corresponding step-by-step approach for solving problems. Finally, the haze management problem is solved to verify the applicability of the approach proposed in this paper. The investigation of this model and its performance paves the way to additional generalizations by other models like q-rung orthopair fuzzy sets.

Risk Perception on Haze Pollution and Willingness to Pay for Self-Protection and Haze Management in Chiang Mai Province, Northern Thailand

Air pollution is an important environmental health risk that affects people worldwide, including those in the Chiang Mai Province, Northern Thailand. A questionnaire survey based on accidental sampling to explore risk perception and willingness to pay (WTP) for self-protection and haze management was conducted via face-to-face interview of 250 households, in one urban and four rural areas (covering one rural plain and three different levels of highland areas). Data were analyzed using the contingent valuation method, a one-way ANOVA, correlation, and stepwise multiple linear regression. Key findings on risk perception found that urban respondents living in the lowest areas were more familiar with and experienced more effects from serious haze, while having the least trust in the local authority’s management to cope with the situation. Influential factors determining familiarity and effect for people in most areas were their harm and severe haze experiences. Comparing WTP for a mask, an air purifier, and local authorities support, respondents in all areas were mainly willing to pay for a mask; this was influenced by various factors. The highest average price of willingness to pay was found in the urban area. The important significant factors that increased WTP for self-protection of urban respondents was severe haze experience, while rural respondents who had a longer stay duration, including married farmers in highland areas with less education, tended to have less WTP for self-protection but more WTP for haze management. Avoiding crop residue burning is the first strategy that should be used to deal with haze pollution. Early burning schedules of the highland people should be formally announced, and prompt risk communication should be implemented by local and central authorities and media practitioners.

Analysis of Urban Landscape Planning Based on Haze Environment

With the acceleration of the urbanization process, the domestic economy has achieved rapid growth, but with the deterioration of the atmospheric environment, especially in cities with rapid industrial development, haze has been the primary air pollutant in recent years. All cities have been hit by haze. Frequent haze weather has seriously affected the lives of urban people, which makes us have to pay attention to how to deal with the haze problem. This article starts with the dangers of haze, analyzes the design principles of urban landscape planning, the active role of plant greening in the management of haze, and the method of arranging landscape plants. It shows that whether from the perspective of aesthetics, or from the function of anti-haze and environmental protection, the selection of a landscape design method that suits local conditions in the design will definitely be one of the major trends in urban landscape planning.

Did Haze Pollution Harm the Quality of Economic Development?—An Empirical Study Based on China’s PM2.5 Concentrations

Based on the PM2.5 haze data of China’s provinces between 2004–2016, this paper systematically explores the impact of haze pollution on the quality of China’s economic development, as well as its transmission mechanisms. This is achieved by measuring the quality of economic development with total factor productivity. Furthermore, this paper innovatively uses precipitation as an instrumental variable for mitigating the endogeneity of the haze pollution variable, by which the impact of haze pollution on the quality of China’s economic development is estimated within the framework of two-stage least squares. It is found that: the haze pollution has degraded the quality of China’s economic development significantly; the labor supply loss, counter urbanization and human capital disruption are the three major transmission channels through which haze pollution affects the quality of China’s economic development; strengthening government’s environmental management is effective in mitigating the adverse impact of haze pollution on the economic development quality; and that China’s unique fiscal decentralization system has exacerbated the negative economic effect of haze pollution. The policy implications of this paper are as follows: Improvement of economic development quality is a prerequisite for the transition of economic development mode; and the governmental management of haze is conducive to enhancing the quality of atmospheric environment and economic development, and to promoting the high-quality development of the Chinese economy.

Addressing Transboundary Haze Through Asean: Singapore’s Normative Constraints

Since 1982, Southeast Asia has experienced almost annual ‘haze’ pollution, caused by smoke from grass, forest and peat fires mostly in Indonesia. The haze affects the health of some 75 million people and the economies of six ASEAN nations. It is the region’s first transboundary environmental crisis that ASEAN is attempting to address collectively. ASEAN level interaction is often guided by the ASEAN Way, and a common debate is whether these norms constrain states from interacting effectively at the regional level. This paper will address this debate using interviews and material compiled during fieldwork in Singapore. While Singapore was one of the first countries to propose a common regional approach to the haze, this paper will illustrate how Singapore has in fact been constrained by the ASEAN Way while engaging with Indonesia and ASEAN. This is reflected in terms of its behavior at the ASEAN forum, statements made, and actions taken. As a result, Singapore has often resorted to other means of engagement, like bilateral and track-two engagement. As Singapore is one of the major ‘victims’ in this equation, this paper serves as important piece of the broader puzzle of why haze management in ASEAN has been less than effective.

Grid management and air quality of Xi’an city

Xi’an was the first city which came up with grid management. Since the implementation of grid management, the air quality of Xi’an has improved quite obviously. But, factors influencing air quality are so many. Thus, we should further launch an empirical research to obtain the grid management impact on air quality. This paper explores it in the way setting policy dummy variable, and the research result manifests that grid management improves the air quality obviously, especially, in the aspect of NO2, SO2. In a nutshell, grid management can provide “Xi’an Model” in the perspective of Haze Management.