Asia Pacific road transportation emissions, 1900–2050
We present an assessment of the historical and future emissions of on-road transportation and strategies to tackle emission challenges in Asia Pacific.
Avoiding high ozone pollution in Delhi, India
Quantify the influence of aerosol light extinction on surface ozone photochemistry, highlight controlling VOC for improving air quality in Delhi.
Vertical profile of particle hygroscopicity and CCN effectiveness during winter in Beijing: insight into the hygroscopicity transition threshold of black carbon
The critical coating thickness (MRc) defining the BC transition between being hydrophobic to hydrophilic was determined by combining HTDMA, CPMA and SP2 measurements.
An evaluation of source apportionment of fine OC and PM2.5 by multiple methods: APHH-Beijing campaigns as a case study
This paper reports an evaluation of multiple source apportionment methods for OC and PM2.5.
Diurnal and weekly patterns of primary pollutants in Beijing under COVID-19 restrictions
Restrictions on movement in Beijing to limit the COVID-19 epidemic tended to change the daily and weekly cycles of emissions of primary pollutants.
Tracer-based characterization of source variations of PM2.5 and organic carbon in Shanghai influenced by the COVID-19 lockdown
Contributions of primary and secondary sources to PM2.5 and organic carbon in Shanghai were quantified before and during the COVID-19 lockdown period.
Long-term trends in the contribution of PM2.5 sources to organic carbon (OC) in the Los Angeles basin and the effect of PM emission regulations
We investigated the long-term variations in the contributions of emission sources to ambient PM2.5 organic carbon (OC) in central Los Angeles (CELA) and Riverside using the Chemical Speciation Network (CSN) database in the 2005–2015 period.
Investigating the background and local contribution of the oxidants in London and Bangkok
Trends of oxidant levels in London and Bangkok roadside sites.
Simulation of primary and secondary particles in the streets of Paris using MUNICH
This study presents the new version of the local-scale model MUNICH, capable to represent the formation of secondary species in gas and particulate phases. A sensitivity test is performed to investigate the formation of secondary aerosols in streets.
Molecular characterization of size-segregated organic aerosols in the urban boundary layer in wintertime Beijing by FT-ICR MS
Our study provides unique information on the vertical profiles and size distribution of urban organic aerosols by FT-ICR MS.
Air quality and health benefits of China’s current and upcoming clean air policies
We estimated China's clean air policies could ensure majority population lives below 35μg m−3, avoiding ∼95.0 thousand premature deaths in 2030.
Formation and growth of sub-3 nm particles in megacities: impact of background aerosols
In polluted urban environments, background aerosols govern the formation and growth of sub-3 nm particles.
A component-specific exposure–mortality model for ambient PM2.5 in China: findings from nationwide epidemiology based on outputs from a chemical transport model
We conducted a whole-population-based epidemiology study using the Chinese Population Census of deaths and PM2.5 concentrations and components, during 2000–2010, to model how chemical composition affects the health impact of PM2.5 exposure.
Introductory Lecture: Air Quality in Megacities
Difference in ambient-personal exposure to PM2.5 and its health impact in local residents in urban and peri-urban Beijing, China: Results of the AIRLESS project
Multiphase chemistry experiment in Fogs and Aerosols in the North China Plain (McFAN): integrated analysis and intensive winter campaign 2018
PM2.5 Pollution in China’s Guanzhong Basin and US’s San Joaquin Valley Mega-Regions
The roles of suburban forest in controlling vertical trace gas and OH reactivity distributions – a case study for Seoul Metropolitan Area.
Insights into air pollution chemistry and sulphate formation from nitrous acid (HONO) measurements during haze events in Beijing
The persistence of a proxy for cooking emissions in megacities: a kinetic study of the ozonolysis of self-assembled films by simultaneous Small & Wide Angle X-ray Scattering (SAXS/WAXS) and Raman microscopy.
Is reducing new particle formation a plausible solution to mitigate particulate air pollution in Beijing and other Chinese megacities?
Using a coupled LES aerosol-radiation model to investigate the importance of aerosol-boundary layer feedback on a Beijing haze episode
Sources of non-methane hydrocarbons in surface air in Delhi, India
Variability of physical meteorology in urban areas at different scales: implications for air quality
About this collection
We are delighted to share with you a selection of the papers associated with a Faraday Discussion on Air quality in megacities. More information about the event may be found here: http://rsc.li/airquality-fd2020. Additional articles will be added to the collection as they are published. The final versions of all the articles presented and a record of the live discussions will be published after the event.
Chemistry plays a role both for the transported and the local emissions, and whereas for the primary (emitted) pollutants, concentrations are likely to be reduced proportionately with reductions in emissions, in the case of secondary pollutants formed within the atmosphere, the relationship between precursor emissions and reaction products is often strongly non-linear. This discussion aims to improve our understanding of the underlying processes responsible; an essential pre-requisite to developing the high quality numerical models of urban air pollutants which are required to develop and test mitigation strategies prior to implementation.