Observation of Brown carbon in PM revealing effects of source-dependence and aging on light absorption.

Organic aerosol (OA) in atmospheric fine particulate matter (PM) has significant impacts on human health, the atmospheric environment, and climate change. Light-absorbing OA, referred to as brown carbon (BrC), is non-negligible during atmospheric processes. However, seasonal and day-night variations, as well as the identification of key driving factors for the dynamic changes in BrC optical properties during continuous haze episodes, remain inadequately understood.

Gridded mobile source emissions with multiple processes and pollutants from 2011 to 2020 in China.

Accurate and comprehensive estimation of mobile source (MS) emissions is essential for air quality management and atmospheric research. However, existing emission inventories often lack sufficient coverage of MS categories, emerging pollutants, and newly developed model parameterizations. Here, we present the Gridded Mobile-source Emission Dataset (GMED), a model-ready emission inventory with detailed source classification and multi-pollutant coverage.

Control of toxicity of fine particulate matter emissions in China.

Fine particulate matter (particulate matter with a diameter of 2.5 μm or less; PM) causes millions of premature deaths globally, but not all particles are equally harmful. Current air-pollution control strategies, prioritizing PM mass reduction, have provided considerable health benefits but further refinements based on differences in the toxicity of various emission sources may provide greater benefits.

Aerosol Water Content Drives Changes in Hydroxymethanesulfonate in Beijing Winter from 2015 to 2021.

Hydroxymethanesulfonate (HMS) is an abundant secondary organosulfur aerosol during winter in the North China Plain, while the variation and affecting factors of HMS with implementing clean air actions remain unclear. Here, we conducted long-term field measurements in Beijing during the winter, including Phase I (2015-2017) and Phase II (2018-2021). Our results showed that HMS concentrations decreased significantly in Phase I, consistent with changes in PM, organic matter (OM), and sulfate, and showed an increasing trend in Phase II in contrast to the decreasing trend of PM, OM, and sulfate.

Strategies for climate-resilient global wind and solar power systems.

Climate change may amplify the frequency and severity of supply-demand mismatches in future power systems with high shares of wind and solar energy. Here we use a dispatch optimization model to assess potential increases in hourly costs associated with the climate-intensified gaps under fixed, high penetrations of wind and solar energy generation. We further explore various strategies to enhance system resilience in the face of future climate change.

Environmental catalytic city: New engine for air pollution control.

Air pollution is a major challenge to the improvement of urban environmental quality. The control of air pollution still faces severe challenges, especially in developing countries, such as ozone pollution control. Ozone is a typical secondary air pollutant, and its formation chemistry from its precursors (NO and volatile organic compounds) is highly nonlinear, which caused the emission reduction of its precursors is not always effective and therefore new assisted approaches to control of ozone pollution are needed.

Insights into transportation CO emissions with big data and artificial intelligence.

The ever-increasing stream of big data offers potential for deep decarbonization in the transportation sector but also presents challenges in extracting interpretable insights due to its complexity and volume. This overview discusses the application of transportation big data to help understand carbon dioxide emissions and introduces how artificial intelligence models, including machine learning (ML) and deep learning (DL), are used to assimilate and understand these data. We suggest using ML to interpret low-dimensional data and DL to enhance the predictability of data with spatial connections across multiple timescales.

Global readiness for carbon neutrality: From targets to action.

The global push for carbon neutrality highlights the need for rigorous assessments of whether national efforts align with stated targets. However, existing evaluations often prioritize commitments over tangible progress, lacking comprehensive and transparent metrics. To bridge this gap, we develop a multidimensional indicator system that evaluates targets, policies, actions, and effectiveness across key areas, including policy implementation, technology deployment, financial investment, and international cooperation.

Enhanced CH emissions from global wildfires likely due to undetected small fires.

Monitoring methane (CH) emissions from terrestrial ecosystems is essential for assessing the relative contributions of natural and anthropogenic factors leading to climate change and shaping global climate goals. Fires are a significant source of atmospheric CH, with the increasing frequency of megafires amplifying their impact. Global fire emissions exhibit large spatiotemporal variations, making the magnitude and dynamics difficult to characterize accurately.

The 2023 report of the synergetic roadmap on carbon neutrality and clean air for China: Carbon reduction, pollution mitigation, greening, and growth.

The response to climate change and air pollution control demonstrates strong synergy across scientific mechanisms, targets, strategies, and governance systems. This report, based on a monitoring indicator system for coordinated governance of air pollution and climate change, employs an interdisciplinary approach combining natural and social sciences. It establishes 20 indicators across five key areas: air pollution and climate change, governance systems and practices, structural transformation and technologies, atmospheric components and emission reduction pathways, and health impacts and co-benefits.

Features of particle-phase PAHs from traffic emissions using tunnel measurement and urban roadside observation in China.

Vehicle emissions are recognized as a primary source of particle-phase polycyclic aromatic hydrocarbons (PAHs), significant contributors to the hazardous properties of PM. This study investigates the profiles of PAHs through measurements conducted in a tunnel and an urban roadside environment in 2020. We quantified real-world vehicle emission factors for mixed fleets in the Zhongshu tunnel in Guizhou, southwest China, and found that the total PAHs had an emission factor of 8.

Molecular Characterization of Organosulfur and Organonitrogen Compounds in Summer and Winter PM via UHPLC-Q-Orbitrap MS/MS.

Organosulfur and organonitrogen compounds (OrgSs and OrgNs) notably influence haze formation, reflecting the intricacies of sulfur and nitrogen chemistry in the atmospheric process. Despite this, a comprehensive understanding of OrgSs and OrgNs remains elusive. Here, we conducted molecular analyses of OrgSs and OrgNs in PM concurrently during three haze episodes in winter and summer from 2016 to 2019.

Ship emission variations during the COVID-19 from global and continental perspectives.

The COVID-19 pandemic and the International Maritime Organization's (IMO) 2020 fuel-switching policy have profoundly impacted global maritime activities, leading to unprecedented changes in shipping emissions. This study aimed to examine the effects from different scales and investigate the underlying drivers. The big data model Ship Emission Inventory Model (SEIM) was updated and applied to analyze the spatiotemporal pattern of global ship emissions as well as the main contributors in 2019 and 2020.

Key factors in epidemiological exposure and insights for environmental management: Evidence from meta-analysis.

In recent years, the precision of exposure assessment methods has been rapidly improved and more widely adopted in epidemiological studies. However, such methodological advancement has introduced additional heterogeneity among studies. The precision of exposure assessment has become a potential confounding factors in meta-analyses, whose impacts on effect calculation remain unclear.

Low-condensation diesel use contributes to winter haze in cold regions of China.

The application of low-condensation diesel in cold regions with extremely low ambient temperatures (-14 to -29 °C) has enabled the operation of diesel vehicles. Still, it may contribute to heavy haze pollution in cold regions during winter. Here we examine pollutant emissions from low-condensation diesel in China.

Synergistic reduction of air pollutants and carbon dioxide emissions in Shanxi Province, China from 2013 to 2020.

Synergistic reduction of air pollutants and carbon dioxide (CO) emissions is currently a key environmental policy in China, yet provincial-level studies remain scarce. To fill the gap, this study developed a coupled emission inventory from 2013 to 2020 in Shanxi, a coal-dependent province critical to China's energy security. This facilitated the investigation of emission trends, primary sources, synergistic effects, and spatial distribution.

Trends and drivers of anthropogenic NO emissions in China since 2020.

Nitrogen oxides (NO), significant contributors to air pollution and climate change, form aerosols and ozone in the atmosphere. Accurate, timely, and transparent information on NO emissions is essential for decision-making to mitigate both haze and ozone pollution. However, a comprehensive understanding of the trends and drivers behind anthropogenic NO emissions from China-the world's largest emitter-has been lacking since 2020 due to delays in emissions reporting.

Cost-effectiveness uncertainty may bias the decision of coal power transitions in China.

A transition away from coal power always maintains a high level of complexity as there are several overlapping considerations such as technical feasibility, economic costs, and environmental and health impacts. Here, we explore the cost-effectiveness uncertainty brought by policy implementation disturbances of different coal power phaseout and new-built strategies (i.e.

Atmospheric impacts and regulation framework of shipping emissions: Achievements, challenges and frontiers.

Currently, over 80% of the international trade volume is carried by sea. Marked by persistent growth, evident atmospheric impacts, intricate mitigation challenges, international shipping has been recognized as one of the most "hard-to-abate" sectors gathering increasing attention from both academic community and governmental sectors in recent years. Against the backdrop of the ambitious climate and clean air objectives, the quantitative shipping emission characterization, impact assessment and policy effectiveness research are not only fundamental to understand the status quo and ramifications of shipping emissions but also beneficial for future emission regulations.

VOC and IVOC emission features and inventory of motorcycles in China.

How did the motorcycle emissions evolve during the economic development in China? To address data gaps, this study firstly measured the volatile organic compound (VOC) and intermediate-volatility organic compound (IVOC) emissions from motorcycles. The results confirmed that the emission control of motorcycles, especially small-displacement motorcycles, significantly lagged behind other gasoline-powered vehicles. For the China IV motorcycles, the average VOC and IVOC emission factors (EFs) were 2.