Seasonal Characteristics of Forecasting Uncertainties in Surface PM_(2.5)Concentration Associated with Forecast Lead Time over the Beijing-Tianjin-Hebei Region

Forecasting uncertainties among meteorological fields have long been recognized as the main limitation on the accuracy and predictability of air quality forecasts.However,the particular impact of meteorological forecasting uncertainties on air quality forecasts specific to different seasons is still not well known.In this study,a series of forecasts with different forecast lead times for January,April,July,and October of 2018 are conducted over the Beijing-Tianjin-Hebei(BTH)region and the impacts of meteorological forecasting uncertainties on surface PM_(2.5)concentration forecasts with each lead time are investigated.With increased lead time,the forecasted PM_(2.5)concentrations significantly change and demonstrate obvious seasonal variations.In general,the forecasting uncertainties in monthly mean surface PM_(2.5)concentrations in the BTH region due to lead time are the largest(80%)in spring,followed by autumn(~50%),summer(~40%),and winter(20%).In winter,the forecasting uncertainties in total surface PM_(2.5)mass due to lead time are mainly due to the uncertainties in PBL heights and hence the PBL mixing of anthropogenic primary particles.In spring,the forecasting uncertainties are mainly from the impacts of lead time on lower-tropospheric northwesterly winds,thereby further enhancing the condensation production of anthropogenic secondary particles by the long-range transport of natural dust.In summer,the forecasting uncertainties result mainly from the decrease in dry and wet deposition rates,which are associated with the reduction of near-surface wind speed and precipitation rate.In autumn,the forecasting uncertainties arise mainly from the change in the transport of remote natural dust and anthropogenic particles,which is associated with changes in the large-scale circulation.

Spatial Variability of PM_(2.5) Pollution in Imbalanced Natural and Socioeconomic Processes: Evidence from the Beijing-Tianjin-Hebei Region of China

Accurately identifying and quantifying the factors influencing PM_(2.5) pollution is of great significance for the prevention and control of pollution. However, the redundancy among potential factors of PM_(2.5) may be overlooked. Meanwhile, the inconsistent spatial distribution of the natural and socioeconomic conditions brings unique implications for the cities within a region, which may lead to an uncertain understanding of the relationship between pollution and environmental factors. This study focused on the Beijing-TianjinHebei(BTH) Region, China, which presents complex and varied background conditions. Potential impact factors on PM_(2.5) were firstly screened by combining systematic cluster analysis with a random forest recursive feature elimination algorithm. Then, the representative multi-factor responsible for PM_(2.5) pollution in the region during the key period of 2014–2018(when the strict national air pollution control policy was implemented). The results showed that the key driving factors of PM_(2.5) pollution in the BTH cities are different, indicating that the uniqueness of a city will have an impact on the leading causes of pollution. Further discussion shows that air control policy provides an effective way to improve air quality. This study aims to deepen the understanding of the risk drivers of air pollution within the BTH Region. In the future, it is recommended that more attention should be paid to the specific differences between the cities when formulating PM_(2.5) concentration control measures.

Assessing the impact of manufacturing agglomeration on environmental pollution in Beijing-Tianjin-Hebei region using spatial panel data model

The Beijing-Tianjin-Hebei region is the vanguard of economic development in northern China.Its manufacturing industry is more and more developed,but environmental pollution is also more serious.Based on the data of 13 cities in Beijing-Tianjin-Hebei region from 2017 to 2021,the paper verifies the impact of manufacturing agglomeration on environmental pollution.Both manufacturing agglomeration and environmental pollution are dependent on spatial distribution.Therefore,the paper selects spatial econometric model to study.First,the spatial lag model and spatial error model are constructed,and then the spatial lag model is selected through the results of OLS regression,LM Test and Hausman test,and the empirical process is carried out.Finally,the empirical results are analyzed and the conclusion is drawn.

Empirical Study on Effect of Industrial Structure Change on Regional Economic Growth of Beijing-Tianjin-Hebei Metropolitan Region

Based on the data of gross domestic product(GDP),industrial added value and the proportion of industrial employees from 2000 to 2008,this paper studies the effect of industrial structure change on the regional economic growth of Beijing-Tianjin-Hebei Metropolitan Region in China using the shift-share method.The results show that:1) In the 21st century,the industrial output of three industries,namely,primary,secondary,and tertiary,and the GDP grew rapidly in the study period.The tertiary industry grew the fastest;it had the largest contribution to the GDP and mean-while had become the most competitive industry in the metropolitan region.2) The development of cities within the region was not balanced.Firstly,compared with Tianjin,Beijing,as one of the two core cities,was more rational in the industrial structure.Secondly,the surrounding eight cities,which are Shijiazhuang,Qinhuangdao,Tangshan,Langfang,Baoding,Cangzhou,Zhangjiakou,and Chengde,were all uncompetitive than the two core cities.3) There was a great industrial gradient in the region(especially between the two core cities and the cities of Tangshan,Baoding,Zhangjia-kou,Chengde,Cangzhou,and Langfang).As a result,it is foreseeable that the industry transfer in the Bei-jing-Tianjin-Hebei Metropolitan Region will be one of the trends in regional development,and the industry transfer is inevitably to promote the regional integration.

Decomposition of factors influencing carbon emissions in the region of Beijing-Tianjin-Hebei,based on the perspective of terminal energy consumption

In order to analyze the factors influencing carbon emissions in the region of Beijing-Tianjin-Hebei and to explore the pathways to developing a low-carbon economy,this paper begins with the terminal energy consumption of three industries and residential consumption,and constructs an identical equation which is composed of population size,level of economic development,energy intensity,the proportion of energy consumption,energy structure,and the coefficient of carbon emissions.Based on the data of terminal energy consumption during 2000-2012,various factors are analyzed and their contribution is measured by Logarithmic Mean Divisia Index(LMDI).The results show that the levels of population and economy have a positive driving effect while energy intensity,energy structure,and carbon intensity have a negative driving effect;the proportion of energy consumption had a negative driving effect prior to 2006,then changed to positive.Among suggestions for a low-carbon economy are controlling population size,improving the quality of economic development,supporting research into new energy technology,accelerating regional integration and optimizing industrial structure,and enhancing environmental protection and spreading the concept of a low-carbon economy.

The status quo and prospect of geothermal resources exploration and development in Beijing-Tianjin-Hebei region in China

The Beijing-Tianjin-Hebei region boasts rich geothermal resources and new achievements have been made in the exploration and development of geothermal resources in this region based on previous regional investigation.In detail,geothermal reservoirs of Gaoyuzhuang Formation of Jixian System and Changcheng System in Xiongan New Area have been recently discovered,opening up the second space of geothermal resources;the calculation method of the recoverable resources of geothermal fluid with reinjection being considered has been improved in Beijing-Tianjin-Hebei region,and uniform comprehensive assessment of shallow geothermal energy,hydrothermal geothermal resources,and hot dry rocks(HDR)geothermal resources in the whole Beijing-Tianjin-Shijiazhuang region has been completed.The scientific research base for cascade development and utilization of geothermal resources in Beijing-Tianjin-Hebei region has applied hydraulic fracturing technology to the geothermal reservoirs in Gaoyuzhuang Formation.As a result,the production capacity doubled and two-stage cascade utilization composed of geothermal power generation and geothermal heating were realized,with the first-phase installed capacity of 280 kW and the geothermal heating is 30000 m2.In this way,a model of the exploration,development,and utilization of geothermal resources formed.Large-scale utilization has become the future trend of geothermal resource development in Beijing-Tianjin-Hebei region,and great efforts shall be made to achieve breakthroughs in reinjection technology,geothermal reservoir reconstruction technology,thermoelectric technology and underground heat exchange technology.

Assessing adaptability of the water resource system to social-ecological systems in the Beijing-Tianjin-Hebei region:Based on the DPSIR-TOPSIS framework

To optimize the overall layout of water resource allocation in the Beijing-Tianjin-Hebei region,the adaptabil‐ity of the water resource system to the regional social-ecological systems has to be enhanced.Based on the driver-pressure-state-impact-response(DPSIR)framework,this study constructs an evaluation index system to analyze the adaptability mechanisms of Beijing-Tianjin-Hebei’s water resource system according to the three major constituent social-ecological systems(i.e.,economic,social,and ecological systems).Moreover,it adopts the technique of order preference similarity to the ideal solution(TOPSIS)to comprehensively evaluate the adaptability of Beijing-Tianjin-Hebei’s water resource system based on three constituent social-ecological systems(i.e.,economic,social,and ecological systems)and identifies the spatiotemporal differentiation char‐acteristics of the region.Our results showed that,①from 2000 to 2020,the adaptability of Beijing-Tianjin Hebei’s water resource system,as a whole,significantly improved.In terms of stages,from 2000 to 2007,the adaptability of the water resource social system was significantly higher than that of economic and ecological systems in the region.From 2008 to 2015,by accelerating the transformation and upgrading of industrial structures,improving the efficiency of economic water utilization,and strengthening the governance of the water ecosystem,the adaptability of water resource economic and ecological systems rapidly improved;how‐ever,that of the water resource ecological system was still the lowest.Additionally,the adaptability of the wa‐ter resource economic system exceeded that of the social system.From 2016 to 2020,the gap in adaptability of the water resource system to all three major constituent systems gradually narrowed.By 2020,the three sys‐tems entered a relatively balanced development stage,with the adaptability of the entire water resource system and the three major constituent systems maintaining a high level.②The economic system was significantly af‐fected by per capita GDP,per capita water resources,and the efficiency of economic water utilization.Addition‐ally,the social system was significantly affected by water consumption per unit of irrigation area.Meanwhile,the ecological system was significantly influenced by precipitation,water pollution discharge performance indi‐cators,and the structure optimization indicators of water supply.According to the evaluation results,we pro‐pose countermeasures and provide recommendations to optimize the overall layout of water resource alloca‐tion and promote the coordinated management of water resources in the Beijing-Tianjin-Hebei region.

Megalopolis:Analyze Beijing-Tianjin-Hebei region based on Urban Design Since 1945

This paper introduces the definition,the features,and advantages of megalopolis according to the book called Urban Design Since 1945,and compares the definition,features,advantages and problems of the megalopolis mentioned in the book with Beijing-Tianjin-Hebei(BTH)urban region.Although megalopolis solves different urban problems for regions,it still faces different problems.In the future,urban planners should pay attention to the sustainable development of urban ecology and make rational use of various resources.

A Brief Analysis of the Causes and Countermeasures of Fog-Haze in Beijing-Tianjin-Hebei Region

Since China broke the blockade and opened the country to the outside world, many township enterprises develop quickly. Together with the pollution caused by China’s coal-burning as the main source of national energy, the pollution caused by small and medium-sized enterprises in towns and villages due to their small investment, low technology level and weak environmental awareness, and the pollution caused by a sharp increase in motor vehicle emissions lead to the fact that fog-haze has been rampant in China’s cities and urban agglomerations for nearly two decades, especially in the Beijing-Tianjin-Hebei region. This paper sorted out the current situation of fog-haze and analyzed the causes of fog-haze from the two aspects of natural and man-made causes, discussed the harms of fog-haze to human body, environment and life, and put forward the concrete measures to solve the fog-haze problem.

Development of Agricultural Product Logistics in Tianjin in the Context of the Coordinated Development Strategy of Beijing-Tianjin-Hebei Region

Since February 26,2014,Chinese president Xi Jinping of the Central Committee of the Communist Party of China listened to the report on the coordinated development of Beijing-Tianjin-Hebei Region and delivered an important speech,and officially raised the coordinated development of Beijing-Tianjin-Hebei Region as a major national strategy,the integration of Beijing-Tianjin-Hebei Region has entered the"fast lane".Guided by accelerating the construction of agricultural product supply areas,agricultural high-tech industry demonstration areas,and agricultural product logistics center areas,Tianjin seizes the opportunity of coordinated development of Beijing-Tianjin-Hebei Region,brings into full play to the advantages of Tianjin s three-dimensional transportation network,perfect market system,high-quality port services,rapid growth of cold chain and e-commerce,to promote the faster and better development of Tianjin s agriculture.In addition,focusing on comprehensively improving Tianjin s regional agricultural product logistics service capabilities,Tianjin is establishing a distribution center for agricultural products,an e-commerce center,and a high-end agricultural product distribution center serving the Beijing-Tianjin-Hebei Region,to promote the construction of Tianjin agricultural product logistics center.

Construction and Implementation Approaches of Ecological Compensation Mechanism for Coordinated Control of Air Pollution in Beijing-Tianjin-Hebei Region

The spatial spillover of air pollution in Beijing-Tianjin-Hebei region makes the territorial governance model inefficient.At the same time,it is facing the contradiction between environmental governance and economic development.So far,there is still no regional long-term mechanism for coordinated governance of air pollution.Ecological compensation theory is becoming an effective guiding theory to coordinate economic and environmental benefits.There is relatively little research on ecological compensation mechanism in the coordinated control of regional air pollution.Ecological compensation mechanism is an effective tool to promote air pollution control.At the same time,regional cooperation can realize the efficient control of air pollution.Scientifically constructing the cross regional cooperative control model of Beijing,Tianjin and Hebei is a favorable way to implement comprehensive control of air pollution.This paper discusses the necessity of ecological compensation mechanism for regional coordinated control of air pollution.Referring to practical experience of provinces and cities that have implemented the ecological compensation mechanism for air pollution control,and the effective way to distribute the compensation amount,compensation subject and compensation standard determination method that can be implemented in Beijing-Tianjin-Hebei region are analyzed,further proposing an effective way to establish an ecological compensation mechanism for regional air pollution collaborative control according to its reality.

Assessing performance of cross-administrative environment governance based on PSR model:An empirical analysis of the Beijing-Tianjin-Hebei region

As an effective environment governance tool,environment governance performance evaluation is an important content and method to promote the modernization of environment governance system and governance ability.The environmental pollution of the Beijing-Tianjin-Hebei region has typical cross-administrative characteristics.Based on the analysis of the major environmental pollution problems in the Beijing-Tianjin-Hebei region,according to the international environment governance PSR model,a performance evaluation system that applies to the environment governance of Beijing-Tianjin-Hebei region is established.Meanwhile,the principal component analysis method is applied to conduct an empirical analysis of the environmental governance panel data for the 13 major cities in the Beijing-Tianjin-Hebei region from 2014 to 2016.The results show that most of the cities in the Beijing-Tianjin-Hebei region attach great importance to reduction of emission and pollutants,continuously alleviating the stress of environmental governance.However,the overall improvement of the environment governance performance in Beijing-Tianjin-Hebei region has presented a polarization imbalance.There is a clear tendency for subjective biases in the implementation of environment governance and a lack of comprehensive and systematic governance.According to the environment governance performance evaluation result of Beijing-Tianjin-Hebei region,the cross-administrative regional environment governance should improve the environment governance performance evaluation system as soon as possible,strengthen the consistency of the environment governance objectives,and implement comprehensive and systematic governance for the regional environment.

Measurement of Urban Economic Gravity of China’s Three Major Agglomerations and Its Implications for the Coordinated Development of the Beijing-Tianjin-Hebei Region

This paper adopts the perspective of urban economic linkage and the modified urban economic gravity model to conduct a comparative analysis of the economic gravity among cities in China’s three major urban agglomerations,including the Beijing-Tianjin-Hebei region,the Yangtze River Delta,and the Pearl River Delta.The results show that,despite the ever-tightening economic linkages among cities in the urban agglomerations,the development of the Beijing-Tianjin-Hebei region falls behind that of the Yangtze River Delta and the Pearl River Delta in terms of coordination,closeness,and balance.The economic linkages among cities in the Beijing-Tianjin-Hebei region are not as cohesive as they could be and display a significant“siphon effect”through Beijing and Tianjin as well as a prominently unidirectional economic flow.This study suggests that efforts should be put into directing the orderly flow of resources from Beijing and Tianjin to cities in Hebei and promoting a balanced economic flow among cities,thus facilitating the coordination of regional development.

Ecological compensation mechanism for Beijing-Tianjin-Hebei region based on footprint balance and footprint deficit

Construction of the ecological compensation mechanism is an important approach to put the“Beijing-Tianjin-Hebei Coordinated Development Plan”into practice and improve the ecological environment of the Beijing-Tianjin-Hebei region.This paper constructs an ecological compensation mechanism for the Beijing-Tianjin-Hebei region based on the footprint balance and footprint deficit after clarifying ecological governance objectives.First,this paper proposes to establish a uniform,hierarchical and classified supply mechanism of ecosystem services according to the classification of land resources,water resources and forest resources for the Beijing-Tianjin-Hebei region.Then,the“Authority with Corresponding Responsibility”for the supply of ecosystem services in the Beijing-Tianjin-Hebei region can be realized through a footprint balance and footprint deficit indicator circulation mechanism.Finally,the scientific and rational ecological compensation standard can be guaranteed through establishing the integrated governance mechanism for ecological compensation in the Beijing-Tianjin-Hebei region and improving the“ecological compensation standard”.The results of this paper can provide sound theoretical support for effectively promoting the improvement of ecosystem services and human well-being in the Beijing-Tianjin-Hebei region.

Analysis of the Higher Education Research in the Chengdu-Chongqing Region:A Comparative Perspective Based on Three Major Economic Circles in China

Drawing on literature regarding higher education research retrieved from the CNKI database from 1997 to 2021,this paper used CiteSpace to analyze the current status of higher education research in the Chengdu-Chongqing economic circle.By comparing it with that in the Beijing-Tianjin-Hebei region,the Guangdong-Hong Kong-Macao Greater Bay Area,and the Yangtze River Delta,this paper concluded that the level of higher education research within a region is in line with the level of the region’s economic and social development.As higher education research in the Chengdu-Chongqing economic circle draws more and more attention,its research areas and topics are becoming increasingly diversified.However,by comparison,the research in this region features a late start and lower participation of researchers and research institutions,resulting in insufficient research in both quantity and quality.Therefore,it is essential to encourage more experts and scholars to participate in higher education research in the Chengdu-Chongqing economic circle.Efforts should also be made to strengthen academic exchanges and cooperation between scholars in Chengdu and Chongqing and establish a long-term cooperation mechanism for higher education research between the two cities.Improved higher education research will definitely facilitate the construction of first-class universities,thus providing human capital and intellectual support for the construction of the Chengdu-Chongqing economic circle.

京津冀地区柴油移动燃烧源污染减排潜力预测

包含柴油车辆和柴油机械的柴油移动燃烧源是现阶段中国进一步持续改善空气质量的重点源。为探究京津冀地区柴油移动燃烧源的污染排放以及减排潜力,在估算2018年京津冀地区柴油车辆和柴油机械污染排放现状的基础上,设置基准情景和5种政策情景,预测2019—2030年不同情景下柴油燃烧源的污染排放趋势,对比分析不同地区、不同源的污染物减排潜力和不同减排措施对不同类型柴油燃烧源的减排效果。结果表明,京津冀地区2018年柴油燃烧源的CO、HC、NO_(x)和PM排放量分别为51.25、22.89、106.52和5.42万t。综合情景下,2030年CO、HC、NO_(x)和PM污染物排放量可分别比基准年减少52.03%、38.58%、71.88%和52.07%。淘汰高排放情景在短时间内的减排效果较好,而长期效果不佳,提升排放标准情景和推广新能源情景的减排潜力会逐年增加,对污染物有较好的减排作用,运输公转铁情景的减排潜力也较好,2030年能有效减少35.13%~45.81%的污染排放。综合情景下柴油车辆和柴油机械的最大减排潜力分别为91.55%和44.69%。此外,CO和NO_(x)的减排潜力主要来源于柴油车辆,而柴油机械对HC和PM的减排效果明显。与其他2个地区相比,天津市的污染减排效果较好,最大减排潜力为80.80%。分类型来看,柴油货车对污染物的减排贡献较大,尤其是重型货车。与工程机械相比,农业机械的污染减排贡献更大,尤其是联合收割机、农用水泵以及三轮车的减排贡献突出。研究结果可为制定柴油移动源的污染控制政策提供科学支持。

京津冀平原区冬季大气环境容量变化:观测与预估

本文基于ERA5再分析数据,探究了京津冀地区冬季大气环境容量(Atmosphere Environmental Capacity,AEC)的时空变化特征以及相关影响因子。结果表明,冬季AEC在京津冀地区表现为西南部低,北部高的分布特征,其低值集中在平原区。京津冀平原区AEC变化与东亚冬季风、边界层高度、边界层内平均风速以及通风强度密切相关。东亚冬季风强、边界层高度高、边界层内平均风速大以及通风强度强,使得AEC偏高,反之亦然。进一步利用区域气候模式RegCM4对3个CMIP5全球气候模式的动力降尺度进行模拟,预估了京津冀平原区冬季AEC在RCP4.5和RCP8.5情景下的变化。结果显示,与1986—2005年相比,两种情景下京津冀平原区冬季AEC在21世纪中、末期都将下降,其中末期下降幅度高于中期、RCP8.5情景下的变化大于RCP4.5情景。上述变化与东亚冬季风减弱、东亚西风急流北移、边界层高度降低以及边界层内平均风速减小有关。

Observational Subseasonal Variability of the PM_(2.5) Concentration in the Beijing-Tianjin-Hebei Area during the January 2021 Sudden Stratospheric Warming

It is still not well understood if subseasonal variability of the local PM_(2.5) in the Beijing-Tianjin-Hebei(BTH)region is affected by the stratospheric state.Using PM_(2.5) observations and the ERA5 reanalysis,the evolution of the air quality in BTH during the January 2021 sudden stratospheric warming(SSW)is explored.The subseasonal variability of the PM_(2.5) concentration after the SSW onset is evidently enhanced.Stratospheric circumpolar easterly anomalies lasted for 53 days during the January-February 2021 SSW with two evident stratospheric pulses arriving at the ground.During the tropospheric wave weakening period and the intermittent period of dormant stratospheric pulses,the East Asian winter monsoon weakened,anomalous temperature inversion developed in the lower troposphere,anomalous surface southerlies prevailed,atmospheric moisture increased,and the boundary layer top height lowered,all of which favor the accumulation of pollutant particulates,leading to two periods of pollution processes in the BTH region.In the phase of strengthened East Asian winter monsoon around the very beginning of the SSW and another two periods when stratospheric pulses had reached the near surface,opposite-signed circulation patterns and meteorological conditions were observed,which helped to dilute and diffuse air pollutants in the BTH region.As a result,the air quality was excellent during the two periods when the stratospheric pulse had reached the near surface.The increased subseasonal variation of the regional pollutant particulates after the SSW onset highlights the important role of the stratosphere in the regional environment and provides implications for the environmental prediction.

Problems and Countermeasures of Beijing-Tianjin-Hebei's location

Regional economic integration is the main trend in the world,the region participate inthe international competition as a whole.China has formed Yangtze River Delta and Pearl River Delta region which have showed strong competitive and plays an important role in enhancing theoverall competitiveness of a country.As the third largest area,Beijing-Tianjin-Hebei'slocation is very important,Beijing,Tianjin and regional development has also attracted great attention of national leaders,China will enhance the economic development of Beijing,Tianjin region to the national strategic level,However,the process of economic integration in Beijing,Tianjin and regional development has been relatively slow,Hebei Province in Beijing and the day Tianjin two big cities have been developing weak,Beijing City,but also faced with the problem of excessive development,This paper points out the problems faced by the integration of Beijing,Tianjin,and puts forward some countermeasures,hoping to discuss how to promote the integration process.

Multi-scale coupling analysis of urbanization and ecosystem services supply-demand budget in the Beijing-Tianjin-Hebei region, China

Rapid economic development and human activities have severely affected ecosystem function.Analysis of the spatial distribution of areas of rapid urbanization is the basis for optimizing urban-ecological spatial design.This paper evaluated the spatial distribution of urbanization in the Beijing-Tianjin-Hebei(BTH)region,and then quantified the ecosystem services(ES)budget in the region based on an ES supply and demand matrix.The results showed that(1)urbanization patterns in the BTH region were relatively stable from 2000 to 2015,with clear patterns of low levels of urbanization in the northwest and high levels in the southeast;(2)areas with positive ES budget values were found throughout the region,except in built-up areas,with high ES supply areas concentrated in the northwest,and high ES demand areas in the southeast;(3)at both the county and prefecture-city levels,urbanization had negative,positive,and negative correlations with ES supply,demand,and budget,respectively;(4)the coupling coordination degree(CCD)increased,with high CCD values in the southeast.Based on these results,policy recommendations include strengthening rational land-use planning and ecosystem management,promoting the coordinated development of the economy and ecological function,and coordinating the provision of production-life-ecological functions.