Visibility-Based PM_2.5 Concentrations in China: 1957–1964 and 1973–2014

China established ground PM_2.5 monitoring network in late 2012 and hence the long-term and large-scale PM_2.5 data were lacking before 2013. In this work, we developed a national-scale spatiotemporal linear mixed effects model to estimate the long-term PM_2.5 concentrations in China from 1957 to 1964 and from 1973 to 2014 using ground visibility monitoring data as the primary predictor. The overall model-fitting and cross-validation <i>R</i>² is 0.72 and 0.71, suggesting that the model is not overfitted. Validation beyond the model year (2014) indicated that the model could accurately estimate historical PM_2.5 concentrations at the monthly (<i>R</i>² = 0.71) level. The historical PM_2.5 estimates suggest that air pollution is not a new environmental issue that occurs in the recent decades but a problem existing in a longer time before 1980. The PM_2.5 concentrations have reached 60–80 μg/m³ in the north part of North China Plain during 1950s–1960s and increased to generally higher than 90 μg/m³ during 1970s. The results also show that the entire China experienced an overall increasing trend (0.19 μg/m³/yr, <i>P</i> < 0.001) in PM_2.5 concentrations from 1957 to 2014 with fluctuations among different periods. This paper demonstrated visibility data allow us to understand the spatiotemporal characteristics of PM_2.5 pollution in China in a long-term

Energy’s Thirst for Water in China

Water scarcity and uneven water distribution pose significant challenges to sustainable development and energy production in China. Based on the International Energy Agency (IEA)’s energy strategy scenarios for China, we evaluated the water withdrawal for energy production from 2011 to 2030. The results show that the amount of water withdrawal will be increased by 77% in 2030, which will aggravate China’s water scarcity risk under current energy strategy. We also observed that 67% of the energy production in China occurs in areas that are facing water scarcity. Moreover, China’s 12th Five-Year Plan of Energy Development does not change the existing energy strategies, and the planned total energy production is much higher than the IEA’s projection, which will result in an increased demand for water resources. However, if China were to apply broad policies to reduce CO₂ emissions, the amount of water withdrawal would also decline compared with current energy strategy. Thus, reforming China’s energy structure and reducing energy usage are not only urgent because of climate challenges and air pollution but also essential to reducing the pressure of water scarcity

Drops of Energy: Conserving Urban Water to Reduce Greenhouse Gas Emissions

Water and energy are two essential resources of modern civilization and are inherently linked. Indeed, the optimization of the water supply system would reduce energy demands and greenhouse gas emissions in the municipal water sector. This research measured the climatic cobenefit of water conservation based on a water flow analysis. The results showed that the estimated energy consumption of the total water system in Changzhou, China, reached approximately 10% of the city’s total energy consumption, whereas the industrial sector was found to be more energy intensive than other sectors within the entire water system, accounting for nearly 70% of the total energy use of the water system. In addition, four sustainable water management scenarios would bring the cobenefit of reducing the total energy use of the water system by 13.9%, and 77% of the energy savings through water conservation was indirect. To promote sustainable water management and reduce greenhouse gas emissions, China would require its water price system, both for freshwater and recycled water, to be reformed

Policy Interactions and Underperforming Emission Trading Markets in China

Emission trading is considered to be cost-effective environmental economic instrument for pollution control. However, the ex post analysis of emission trading program found that cost savings have been smaller and the trades fewer than might have been expected at the outset of the program. Besides policy design issues, pre-existing environmental regulations were considered to have a significant impact on the performance of the emission trading market in China. Taking the Jiangsu sulfur dioxide (SO₂) market as a case study, this research examined the impact of policy interactions on the performance of the emission trading market. The results showed that cost savings associated with the Jiangsu SO₂ emission trading market in the absence of any policy interactions were CNY 549 million or 12.5% of total pollution control costs. However, policy interactions generally had significant impacts on the emission trading system; the lone exception was current pollution levy system. When the model accounted for all four kinds of policy interactions, the total pollution control cost savings from the emission trading market fell to CNY 39.7 million or 1.36% of total pollution control costs. The impact of policy interactions would reduce 92.8% of cost savings brought by emission trading program

How Do the Chinese Perceive Ecological Risk in Freshwater Lakes?

<div><p>In this study, we explore the potential contributions of a risk perception framework in understanding public perceptions of unstable ecosystems. In doing so, we characterize one type of common ecological risk– harmful algal blooms (HABs)–in four of the most seriously eutrophicated freshwater lakes in China. These lakes include Chaohu, Dianchi, Hongze, and Taihu, where a total of 2000 residents living near these sites were interviewed. Regional discrepancies existed in the pilot study regarding public perceptions of ecological changes and public concerns for ecological risk. Comparing HABs and other kinds of risks (earthquake, nuclear, and public traffic) through the psychometric paradigm method, <i>Knowledge</i>, <i>Effect</i>, and <i>Trust</i> were three key factors formulating the risk perception model. The results indicated that <i>Knowledge</i> and risk tolerance levels had significant negative correlations in the higher economic situation while correlations in the lower economic situation were significantly positive. <i>Effect</i> and risk tolerance levels had significant negative correlations in the high and middle education situation while correlations in the low education situation were close to zero or insignificant. For residents from Taihu with comparatively higher economic and educational levels, more investment in risk prevention measures and stronger policies are needed. And for residents from Hongze and Dianchi with comparatively low economic and educational levels, improvement of the government’s credibility (<i>Trust</i>) was the most important factor of risk tolerance, so efforts to eliminate ecological problems with the stepwise development of economic and educational levels should be implemented and gradually strengthened. In turn, this could prevent public discontent and ensure support for ecological protection policies.</p></div

Appendix B. The corresponding model equations for all defined activities with respect to the P metabolism model for the case study area of Shucheng County, China.

The corresponding model equations for all defined activities with respect to the P metabolism model for the case study area of Shucheng County, China

Estimating Ground-Level PM_2.5 in China Using Satellite Remote Sensing

Estimating ground-level PM_2.5 from satellite-derived aerosol optical depth (AOD) using a spatial statistical model is a promising new method to evaluate the spatial and temporal characteristics of PM_2.5 exposure in a large geographic region. However, studies outside North America have been limited due to the lack of ground PM_2.5 measurements to calibrate the model. Taking advantage of the newly established national monitoring network, we developed a national-scale geographically weighted regression (GWR) model to estimate daily PM_2.5 concentrations in China with fused satellite AOD as the primary predictor. The results showed that the meteorological and land use information can greatly improve model performance. The overall cross-validation (CV) <i>R</i>² is 0.64 and root mean squared prediction error (RMSE) is 32.98 μg/m³. The mean prediction error (MPE) of the predicted annual PM_2.5 is 8.28 μg/m³. Our predicted annual PM_2.5 concentrations indicated that over 96% of the Chinese population lives in areas that exceed the Chinese National Ambient Air Quality Standard (CNAAQS) Level 2 standard. Our results also confirmed satellite-derived AOD in conjunction with meteorological fields and land use information can be successfully applied to extend the ground PM_2.5 monitoring network in China

Informing Urban Flood Risk Adaptation by Integrating Human Mobility Big Data During Heavy Precipitation

Understanding the impact of heavy precipitation on human mobility is critical for finer-scale urban flood risk assessment and achieving sustainable development goals #11 to build resilient and safe cities. Using ∼2.6 million mobile phone signal data collected during the summer of 2018 in Jiangsu, China, this study proposes a novel framework to assess human mobility changes during rainfall events at a high spatial granularity (500 m grid cell). The fine-scale mobility map identifies spatial hotspots with abnormal clustering or reduced human activities. When aggregating to the prefecture-city level, results show that human mobility changes range between −3.6 and 8.9%, revealing varied intracity movement across cities. Piecewise structural equation modeling analysis further suggests that city size, transport system, and crowding level directly affect mobility responses, whereas economic conditions influence mobility through multiple indirect pathways. When overlaying a historical urban flood map, we find such human mobility changes help 23 cities reduce 2.6% flood risks covering 0.45 million people but increase a mean of 1.64% flood risks in 12 cities covering 0.21 million people. The findings help deepen our understanding of the mobility pattern of urban dwellers after heavy precipitation events and foster urban adaptation by supporting more efficient small-scale hazard management

Can China Comply with Its 12th Five-Year Plan on Industrial Emissions Control: A Structural Decomposition Analysis

China’s rapid economic growth has caused serious environmental problems, resulting in the implementation of two major measuresend-of-pipe facilities and the phasing out of backward capacityto reduce China’s industrial emissions as part of its 11th Five-Year Plan (FYP, 2006–2010). It is important to determine whether China can meet the targets set forth in its 12th FYP (2011–2015) for industrial pollution reduction using these same solutions. In this paper, structural decomposition analysis (SDA) was used to identify the contributions of the adopted measuresas well as other underlying factorsand to evaluate the feasibility of the reduction target in China’s 12th FYP. Results show that the decrease in major industrial pollutant emissions achieved during the 11th FYP resulted from improved technological efficiency, including end-of-pipe abatement efficiency and pollutant generation intensity. The same measures adopted during China’s 12th FYP can address the problem of industrial wastewater emissions resulting from economic growth when the economic structure is kept constant. But it may not fulfill its commitment of reducing industrial atmospheric pollutants emissions unless the economic structure and growth patterns are drastically reformed

Effect of Lead Pollution Control on Environmental and Childhood Blood Lead Level in Nantong, China: An Interventional Study

Children’s blood lead levels and prevalence of lead poisoning in China are significantly higher than in developed countries, though a substantial decrease has been observed. Since 2011, strict lead control policies in lead-related industries have been implemented in China, but the success of these policies is unknown. In this study, we collected environmental samples, questionnaire data, and blood samples from 106 children from 1 to 14 years old, before and after implementation of lead-usage control policy in wire rope factories by local government in Zhuhang, Nantong in 2012. Results showed that, one year after the lead control, lead concentrations sharply decreased in both environmental and biological samples with a decrease of 0.43 μg/m³ (−84.3%) in ambient air samples, 0.22 mg/kg (−36.1%) in vegetable samples, 441.1 mg/kg (−43.7%) in dust samples, and 6.24 μg/dL (−51.5%) in childhood blood lead levels (BLL). This study demonstrates the success of lead control policies in promoting the prevention and control of childhood lead poisoning in Nantong, China