2025
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Plain Language Summary
Navarro-Barbosa et al. (2025)
Brown carbon (BrC) absorbs ultraviolet (UV) and visible light, influencing climate. This study explores BrC’s imaginary refractive index (k) using data from 12 European sites. Residential emissions are a major organic aerosol (OA) source in winter, while secondary organic aerosol (SOA) dominates in summer. Source-specific k values were derived, improving model accuracy. The findings highlight BrC’s climate impact and emphasize source-specific constraints in atmospheric models.
2024
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PM2.5 Concentration Gap Reduction between Typical Urban and Nonurban China from 2000 to 2023
Guo et al. (2024)
Since 2013, stringent clean air initiatives have significantly improved air quality in China. Utilizing fine particulate matter (PM2.5) and its chemical composition data from 2000 to 2023, we observed a reduction in the disparity of PM2.5 concentrations between urban and non-urban areas. This reduction is linked to stricter emission controls in urban areas and the relocation of some emission sources to non-urban areas. However, the specific chemical constituents of PM2.5 and the driving factors behind these changes remain to be fully elucidated. This study analyzes the proportions of PM2.5 components in major cities such as Beijing, Shanghai, and Guangzhou and their surrounding non-urban areas.
Unveiling the health impacts of air pollution transport in China
Ding et al. (2024)
The transport of atmospheric pollutants plays a pivotal role in regional air pollution, highlighting critical concerns over the unequal health outcomes that arise from such transport. The intensification of control measures necessitates a national perspective to comprehend the health impacts due to pollution transport. Our study establishes an integrated assessment framework that combines an emission-concentration response surface model with a health impact evaluation model to analyse the nationwide health impacts of PM2.5 and O3 pollution transport across China’s 31 provinces.
FUME 2.0 – Flexible Universal processor for Modeling Emissions
Belda et al. (2024)
For modeling atmospheric chemistry, it is necessary to provide data on emissions of pollutants. These can come from various sources and in various forms, and preprocessing of the data to be ingestible by chemistry models can be quite challenging. We developed the FUME processor to use a database layer that internally transforms all input data into a rigid structure, facilitating further processing to allow for emission processing from the continental to the street scale.
Cloud response to co-condensation of water and organic vapors over the boreal forest
Heikkinen et al. (2024)
The organic vapor condensation with water vapor (co-condensation) in rising air below clouds is modeled in this work over the boreal forest where the air is rich in organic vapors. We show that the number of cloud droplets can increase by 20 % if considering co-condensation. The enhancements are even larger if the air contains many small, naturally produced aerosol particles. Such conditions are most frequently met in spring in the boreal forest.
Bartík et al. (2024)
The presented study deals with the attribution of fine particulate matter (PM2.5) concentrations to anthropogenic emissions over Central Europe using regional-scale models. It calculates the present-day contributions of different emissions sectors to concentrations of PM2.5 and its secondary components. Moreover, the study investigates the effect of chemical non-linearities by using multiple source attribution methods and secondary organic aerosol calculation methods.
Savenets et al. (2024)
Wildfires frequently occur in Ukraine during agricultural open-burning seasons in spring and autumn. High aerosol concentrations from fire emissions can significantly affect meteorological processes via direct and indirect aerosol effects. To study these impacts, we selected a severe wildfire episode from April 2020 in the Chornobyl Exclusion Zone (CEZ) and its surrounding area as a case study.
Kulmala et al. (2024)
Atmospheric new particle formation (NPF), together with secondary production of particulate matter in the atmosphere, dominates aerosol particle number concentrations and sub-micron particle mass loads in many environments globally. In this opinion paper, we describe the paradigm shift to understand NPF in a continuous way instead of using traditional binary event–non-event analysis.
Heslin-Rees (2024)
Light-absorbing atmospheric particles (e.g. black carbon – BC) exert a warming effect on the Arctic climate. We show that the amount of particle light absorption decreased from 2002 to 2023. We conclude that in addition to reductions in emissions of BC, wet removal plays a role in the long-term reduction of BC in the Arctic, given the increase in surface precipitation experienced by air masses arriving at the site. The potential impact of biomass burning events is shown to have increased.
Akritidis et al. (2024)
Long-term exposure to ambient ozone (O3) is associated with excess respiratory mortality. Pollution emissions, demographic, and climate changes are expected to drive future ozone-related mortality. Here, we assess global mortality attributable to ozone according to an Intergovernmental Panel on Climate Change (IPCC) Shared Socioeconomic Pathway (SSP) scenario applied in Coupled Model Intercomparison Project Phase 6 (CMIP6) models, projecting a temperature increase of about 3.6 °C by the end of the century.
2023
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Casqero-Vera et al. (2023)
Aliaga et al. (2023)
Kulmala et al. (2023)
This is the first study of the effect of mineral dust on the inhibition/promotion of new particle formation (NPF) events in different dust-influenced areas. Unexpectedly, the research shows that the occurrence of NPF events is highly frequent during mineral dust outbreaks, occurring even during extreme dust outbreaks. It also shows that the occurrence of NPF events during mineral dust outbreaks significantly affects the potential cloud condensation nuclei budget.
We introduce a novel method for evaluating days when small particles are formed in the atmosphere. Instead of the traditional binary division between event and non-event days, our method, known as “nano ranking analysis”, provides a continuous, non-categorical metric for each day. By utilizing data from Hyytiälä, Finland, we show that our approach effectively quantifies these events. This innovative method paves the way for a deeper understanding of the factors influencing particle formation.
To be able to meet global grand challenges, we need comprehensive open data with proper metadata. In this opinion paper, we describe the SMEAR (Station for Measuring Earth surface – Atmosphere Relations) concept and include several examples (cases), such as new particle formation and growth, feedback loops and the effect of COVID-19, and what has been learned from these investigations. The future needs and the potential of comprehensive observations of the environment are summarized.
Zhou et al. (2023)
A Green Sahara with enhanced rainfall and larger vegetation cover existed in northern Africa about 6000 years ago. Biosphere–atmosphere interactions are found to be critical to explaining this wet period. Based on modeled vegetation reconstruction data, dust emissions and aerosol formation are simulated, which are key factors in biosphere–atmosphere interactions. The results also provide a benchmark of aerosol climatology for future paleo-climate simulation experiments.
Sink, Source or Something In-Between? Net Effects of Precipitation on Aerosol Particle Populations
Khadir et al. (2023)
Atmospheric aerosols, clouds, and precipitation play a significant role in Earth’s temperature regulation and air quality. While clouds and precipitation help remove particles from the atmosphere, recent research suggests rain could also introduce new particles. However, the extent of this particle source and its impact on climate are still unknown. This study analyzes years of observational data from clean environments and discovered that after precipitation, new particles were sometimes added to the surface atmosphere. The findings highlight the importance of considering how clouds and rain recycle particles when studying air quality and climate.
Okuljar et al. (2023)
Highly oxygenated organic molecules (HOMs) form secondary organic aerosol that affects air quality and health. This study demonstrates that in a moderately polluted city with abundant vegetation, the composition of HOMs is largely controlled by the effect of NOx on the biogenic volatile organic compound oxidation. Comparing the results from two nearby stations, the results show that HOM composition and formation pathways can change considerably within small distances in urban environments.
Things are not always as they first seem in ambient aerosol measurements. Observations of decreasing particle sizes are often interpreted as resulting from particle evaporation. This paper shows that such observations can counter-intuitively be explained by particles that are constantly growing in size. This requires one to account for the previous movements of the observed air. Our explanation implies a larger number of larger particles, meaning more significant effects of aerosols on climate and health.
Toward a versatile spaceborne architecture for immediate monitoring of the global methane pledge
Wang et al. (2023)
Substantial advances have been made in recent years toward detecting and quantifying methane super-emitters from space. However, such advances have rarely been expanded to measure the global methane pledge because large-scale swaths and high-resolution sampling have not been coordinated. Here we present a versatile spaceborne architecture that can juggle planet-scale and plant-level methane retrievals, challenge official emission reports, and remain relevant for stereoscopic measurements.
Bornstein and Baklanov (2023)