The atmospheric aerosol over Siberia, as seen from the 300 m ZOTTO tower

This report describes a unique setup for aerosol measurements at the new long-term Tall Tower monitoring facility near Zotino, Siberia (ZOTTO). Through two inlets at 50 and 300 m aerosol particle number size distributions are measured since September 2006 in the size range 15–835 nanometer dry diameter. Until the end of May 2007 total number (N300) concentrations at 300 m height ranged between 400 cm-3 (5%) and 4000 cm-3 (95%) with a median of 1200 cm-3, which is rather high for a nearly uninhabited boreal forest region during the low productivity period of the year. Fitting 1-h average distributions with a maximum of four lognormal functions yielded frequent ultrafine modes below 20 nm at 50 m height than at 300 m, whereas the latter height more frequently showed an aged nucleation mode near 30 nm. The positions of Aitken (≈80 nm) and accumulation modes (≈210 nm) were very similar at both inlet heights, the very sharp latter one being the most frequent of all modes. The encouraging first results let us expect exciting newfindings during the summer period with frequent forest fires and secondary particle sources from vegetation emissions

Particle number emission rates of aerosol sources in 40 German households and their contributions to ultrafine and fine particle exposure

More representative data on source-specific particle number emission rates and associated exposure in European households are needed. In this study, indoor and outdoor particle number size distributions (10–800 nm) were measured in 40 German households under real-use conditions in over 500 days. Particle number emission rates were derived for around 800 reported indoor source events. The highest emission rate was caused by burning candles (5.3 × 1013 h−1). Data were analyzed by the single-parameter approach (SPA) and the indoor aerosol dynamics model approach (IAM). Due to the consideration of particle deposition, coagulation, and time-dependent ventilation rates, the emission rates of the IAM approach were about twice as high as those of the SPA. Correction factors are proposed to convert the emission rates obtained from the SPA approach into more realistic values. Overall, indoor sources contributed ~ 56% of the daily-integrated particle number exposure in households under study. Burning candles and opening the window leads to seasonal differences in the contributions of indoor sources to residential exposure (70% and 40% in the cold and warm season, respectively). Application of the IAM approach allowed to attribute the contributions of outdoor particles to the penetration through building shell and entry through open windows (26% and 15%, respectively). © 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Lt

Aerosol pollution maps and trends over Germany with hourly data at four rural background stations from 2009 to 2018

A total of 10 years of hourly aerosol and gas data at four rural German stations have been combined with hourly back trajectories to the stations and inventories of the European Emissions Database for Global Atmospheric Research (EDGAR), yielding pollution maps over Germany of PM10, particle number concentrations, and equivalent black carbon (eBC). The maps reflect aerosol emissions modified with atmospheric processes during transport between sources and receptor sites. Compared to emission maps, strong western European emission centers do not dominate the downwind concentrations because their emissions are reduced by atmospheric processes on the way to the receptor area. PM10, eBC, and to some extent also particle number concentrations are rather controlled by emissions from southeastern Europe from which pollution transport often occurs under drier conditions. Newly formed particles are found in air masses from a broad sector reaching from southern Germany to western Europe, which we explain with gaseous particle precursors coming with little wet scavenging from this region. Annual emissions for 2009 of PM10, BC, SO2, and NOx were accumulated along each trajectory and compared with the corresponding measured time series. The agreement of each pair of time series was optimized by varying monthly factors and annual factors on the 2009 emissions. This approach yielded broader summer emission minima than published values that were partly displaced from the midsummer positions. The validity of connecting the ambient concentration and emission of particulate pollution was tested by calculating temporal changes in eBC for subsets of back trajectories passing over two separate prominent emission regions, region A to the northwest and B to the southeast of the measuring stations. Consistent with reported emission data the calculated emission decreases over region A are significantly stronger than over region B

Mobiler Aerosolstandard - Entwicklung eines mobilen Aerosolstandards

Ein mobiler Aerosolstandard für ultrafeine Partikel wurde als neue Möglichkeit zur Qualitätskontrolle für innovative Umweltmessungen in Luftgütemessnetzen entwickelt. Die Bestimmung der Anzahl ultrafeiner Partikel in Ergänzung zur Überwachung von Feinstaub PM10 oder PM2.5 eröffnet neue Möglichkeiten, die Luftqualität zukünftig besser beurteilen zu können. Ultrafeine Partikel sind ein zweckmäßiger Indikator, um z. B. die positive Wirkung einer Umweltzone in Luftreinhalteplänen nachzuweisen

Ion — particle interactions during particle formation and growth at a coniferous forest site in central Europe

In this work, we examined the interaction of ions and neutral particles during atmospheric new particle formation (NPF) events. The analysis is based on simultaneous field measurements of atmospheric ions and total particles using a neutral cluster and air ion spectrometer (NAIS) across the diameter range 2–25 nm. The Waldstein research site is located in a spruce forest in NE Bavaria, Southern Germany, known for enhanced radon concentrations, presumably leading to elevated ionization rates. Our observations show that the occurrence of the ion nucleation mode preceded that of the total particle nucleation mode during all analyzed NPF events. The time difference between the appearance of 2 nm ions and 2 nm total particles was typically about 20 to 30 min. A cross correlation analysis showed a rapid decrease of the time difference between the ion and total modes during the growth process. Eventually, this time delay vanished when both ions and total particles did grow to larger diameters. Considering the growth rates of ions and total particles separately, total particles exhibited enhanced growth rates at diameters below 15 nm. This observation cannot be explained by condensation or coagulation, because these processes would act more efficiently on charged particles compared to neutral particles. To explain our observations, we propose a mechanism including recombination and attachment of continuously present cluster ions with the ion nucleation mode and the neutral nucleation mode, respectively

Ultrafine particles in cities

Ultrafine particles (UFPs; diameter less than 100 nm) are ubiquitous in urban air, and an acknowledged risk to human health. Globally, the major source for urban outdoor UFP concentrations is motor traffic. Ongoing trends towards urbanisation and expansion of road traffic are anticipated to further increase population exposure to UFPs. Numerous experimental studies have characterised UFPs in individual cities, but an integrated evaluation of emissions and population exposure is still lacking. Our analysis suggests that the average exposure to outdoor UFPs in Asian cities is about four-times larger than that in European cities but impacts on human health are largely unknown. This article reviews some fundamental drivers of UFP emissions and dispersion, and highlights unresolved challenges, as well as recommendations to ensure sustainable urban development whilst minimising any possible adverse health impacts

Aerosol Particle and Black Carbon Emission Factors of Vehicular Fleet in Manila, Philippines

Poor air quality has been identified as one of the main risks to human health, especially in developing regions, where the information on physical chemical properties of air pollutants is lacking. To bridge this gap, we conducted an intensive measurement campaign in Manila, Philippines to determine the emission factors (EFs) of particle number (PN) and equivalent black carbon (BC). The focus was on public utility jeepneys (PUJ), equipped with old technology diesel engines, widely used for public transportation. The EFs were determined by aerosol physical measurements, fleet information, and modeled dilution using the Operational Street Pollution Model (OSPM). The results show that average vehicle EFs of PN and BC in Manila is up to two orders of magnitude higher than European emission standards. Furthermore, a PUJ emits up to seven times more than a light-duty vehicles (LDVs) and contribute to more than 60% of BC emission in Manila. Unfortunately, traffic restrictions for heavy-duty vehicles do not apply to PUJs. The results presented in this work provide a framework to help support targeted traffic interventions to improve urban air quality not only in Manila, but also in other countries with a similar fleet composed of old-technology vehicles

Ultrafine particles in cities

Peer reviewe

A holistic modeling framework for estimating the influence of climate change on indoor air quality

The IPCC 2021 report predicts rising global temperatures and more frequent extreme weather events in the future, which will have different effects on the regional climate and concentrations of ambient air pollutants. Consequently, changes in heat and mass transfer between the inside and outside of buildings will also have an increasing impact on indoor air quality. It is therefore surprising that indoor spaces and occupant well-being still play a subordinate role in the studies of climate change. To increase awareness for this topic, the Indoor Air Quality Climate Change (IAQCC) model system was developed, which allows short and long-term predictions of the indoor climate with respect to outdoor conditions. The IAQCC is a holistic model that combines different scenarios in the form of submodels: building physics, indoor emissions, chemical-physical reaction and transformation, mold growth, and indoor exposure. IAQCC allows simulation of indoor gas and particle concentrations with outdoor influences, indoor materials and activity emissions, particle deposition and coagulation, gas reactions, and SVOC partitioning. These key processes are fundamentally linked to temperature and relative humidity. With the aid of the building physics model, the indoor temperature and humidity, and pollutant transport in building zones can be simulated. The exposure model refers to the calculated concentrations and provides evaluations of indoor thermal comfort and exposure to gaseous, particulate, and microbial pollutants.Peer reviewe