2021 - 2022

Air quality observations onboard commercial and targeted Zeppelin flights in Germany – a platform for high-resolution trace-gas and aerosol measurements within the planetary boundary layer
June 27, 2022

Air quality observations onboard commercial and targeted Zeppelin flights in Germany – a platform for high-resolution trace-gas and aerosol measurements within the planetary boundary layer

A Zeppelin airship was used as a platform for in situ measurements of greenhouse gases and short-lived air pollutants within the planetary boundary layer (PBL) in Germany.

Oxidation of low-molecular-weight organic compounds in cloud droplets: global impact on tropospheric oxidants
July 1, 2021

Oxidation of low-molecular-weight organic compounds in cloud droplets: global impact on tropospheric oxidants

In liquid cloud droplets, superoxide anion () is known to quickly consume ozone (O3(aq)), which is relatively insoluble. The significance of this reaction as a tropospheric O3 sink is sensitive to the abundance of and therefore to the production of its main precursor, the hydroperoxyl radical (HO2(aq)).

Oxidation of low-molecular-weight organic compounds in cloud droplets: development of the Jülich Aqueous-phase Mechanism of Organic Chemistry (JAMOC) in CAABA/MECCA (version 4.5.0)
July 1, 2021

Oxidation of low-molecular-weight organic compounds in cloud droplets: development of the Jülich Aqueous-phase Mechanism of Organic Chemistry (JAMOC) in CAABA/MECCA (version 4.5.0)

The Jülich Aqueous-phase Mechanism of Organic Chemistry (JAMOC) is developed and implemented in the Module Efficiently Calculating the Chemistry of the Atmosphere (MECCA; version 4.5.0). JAMOC is an explicit in-cloud oxidation scheme for oxygenated volatile organic compounds (OVOCs), suitable for global model applications.

The impact of organic pollutants from Indonesian peatland fires on the tropospheric and lower stratospheric composition
July 27, 2021

The impact of organic pollutants from Indonesian peatland fires on the tropospheric and lower stratospheric composition

The particularly strong dry season in Indonesia in 2015, caused by an exceptionally strong El Niño, led to severe peatland fires resulting in high volatile organic compound (VOC) biomass burning emissions.

Simulation of organics in the atmosphere: evaluation of EMACv2.54 with the Mainz Organic Mechanism (MOM) coupled to the ORACLE (v1.0) submodel
April 1, 2022

Simulation of organics in the atmosphere: evaluation of EMACv2.54 with the Mainz Organic Mechanism (MOM) coupled to the ORACLE (v1.0) submodel

An updated and expanded representation of organics in the chemistry general circulation model EMAC (ECHAM5/MESSy for Atmospheric Chemistry) has been evaluated.

Ubiquitous atmospheric production of organic acids mediated by cloud droplets
May 12, 2021

Ubiquitous atmospheric production of organic acids mediated by cloud droplets

Atmospheric acidity is increasingly determined by carbon dioxide and organic acid Among the latter, formic acid facilitates the nucleation of cloud droplets and contributes to the acidity of clouds and rainwate.

Particle-filter-based volcanic ash emission inversion applied to a hypothetical sub-Plinian Eyjafjallajökull eruption using the Ensemble for Stochastic Integration of Atmospheric Simulations (ESIAS-chem) version 1.0
February 3, 2022

Particle-filter-based volcanic ash emission inversion applied to a hypothetical sub-Plinian Eyjafjallajökull eruption using the Ensemble for Stochastic Integration of Atmospheric Simulations (ESIAS-chem) version 1.0

A particle-filter-based inversion system is presented, which enables us to derive time- and altitude-resolved volcanic ash emission fluxes along with its uncertainty. The system assimilates observations of volcanic ash column mass loading as retrieved from geostationary satellites.

GPU Optimizations for Atmospheric Chemical Kinetics
January 20, 2021

GPU Optimizations for Atmospheric Chemical Kinetics

We present a series of optimizations to alleviate stack memory overflow issues and improve overall performance of GPU computational kernels in atmospheric chemical kinetics model simulations.

A revised dry deposition scheme for land–atmosphere exchange of trace gases in ECHAM/MESSy v2.54
January 26, 2021

A revised dry deposition scheme for land–atmosphere exchange of trace gases in ECHAM/MESSy v2.54

Dry deposition to vegetation is a major sink of ground-level ozone and is responsible for about 20 % of the total tropospheric ozone loss. Its parameterization in atmospheric chemistry models represents a significant source of uncertainty for the global tropospheric ozone budget and might account for the mismatch with observations.

The global impacts of COVID-19 lockdowns on urban air pollution: A critical review and recommendations
April 2, 2021

The global impacts of COVID-19 lockdowns on urban air pollution: A critical review and recommendations

The coronavirus-19 (COVID-19) pandemic led to government interventions to limit the spread of the disease which are unprecedented in recent history; for example, stay at home orders led to sudden decreases in atmospheric emissions from the transportation sector.

Uptake of Water-soluble Gas-phase Oxidation Products Drives Organic Particulate Pollution in Beijing
March 22, 2021

Uptake of Water-soluble Gas-phase Oxidation Products Drives Organic Particulate Pollution in Beijing

Despite the recent decrease in pollution events in Chinese urban areas, the World Health Organization air quality guideline values are still exceeded. Observations from monitoring networks show a stronger decrease of organic aerosol directly emitted to the atmosphere relative to secondary organic aerosol (SOA) generated from oxidation processes.

Influence of aromatics on tropospheric gas-phase composition
February 23, 2021

Influence of aromatics on tropospheric gas-phase composition

Aromatics contribute a significant fraction to organic compounds in the troposphere and are mainly emitted by anthropogenic activities and biomass burning. Their oxidation in lab experiments is known to lead to the formation of ozone and aerosol precursors.

MesSBAR—Multicopter and Instrumentation for Air Quality Research
April 15, 2022

MesSBAR—Multicopter and Instrumentation for Air Quality Research

Air quality measurements usually consist of ground-based instrumentation at fixed locations. However, vertical profiles of pollutants are of interest for understanding processes, distribution, dilution and concentration.

Efficient Production of Carbonyl Sulfide in the Low-NOx Oxidation of Dimethyl Sulfide
January 19, 2022

Efficient Production of Carbonyl Sulfide in the Low-NOx Oxidation of Dimethyl Sulfide

The oxidation of carbonyl sulfide (OCS) is the primary, continuous source of stratospheric sulfate aerosol particles, which can scatter shortwave radiation and catalyze heterogeneous reactions in the stratosphere.

Unimolecular and water reactions of oxygenated and unsaturated Criegee intermediates under atmospheric conditions
February 25, 2022

Unimolecular and water reactions of oxygenated and unsaturated Criegee intermediates under atmospheric conditions

Ozonolysis of unsaturated hydrocarbons (VOCs) is one of the main oxidation processes in the atmosphere. The stabilized Criegee intermediates (SCI) formed are highly reactive oxygenated species that potentially influence the HOx, NOx and SOx cycles, and affect aerosol formation by yielding low-volatility oxygenated compounds.

Estimation of mechanistic parameters in the gas-phase reactions of ozone with alkenes for use in automated mechanism construction
May 11, 2022

Estimation of mechanistic parameters in the gas-phase reactions of ozone with alkenes for use in automated mechanism construction

Reaction with ozone is an important atmospheric removal process for alkenes. The ozonolysis reaction produces carbonyls and carbonyl oxides (Criegee intermediates, CI), which can rapidly decompose to yield a range of closed shell and radical products, including OH radicals.

Evaluation of the coupled high-resolution atmospheric chemistry model system MECO(n) using in situ and MAX-DOAS NO2 measurements
July 30, 2021

Evaluation of the coupled high-resolution atmospheric chemistry model system MECO(n) using in situ and MAX-DOAS NO2 measurements

We present high spatial resolution (up to 2.2×2.2 km2) simulations focussed over south-west Germany using the online coupled regional atmospheric chemistry model system MECO(n) (MESSy-fied ECHAM and COSMO models nested n times).

A comparison between mobile and stationary gas chromatography–mass spectrometry devices for analysis of complex volatile profiles
November 17, 2022

A comparison between mobile and stationary gas chromatography–mass spectrometry devices for analysis of complex volatile profiles

On-site analysis of volatile organic compounds (VOCs) with miniaturized gas chromatography–mass spectrometry (GC–MS) systems is a very rapidly developing field of application. While, on the one hand, major technological advances are improving the availability of these systems on the market, on the other hand, systematic studies to assess the performance of such instruments are still lacking.

Observational Insights into Isoprene Secondary Organic Aerosol Formation through the Epoxide Pathway at Three Urban Sites from Northern to Southern China
March 2, 2022

Observational Insights into Isoprene Secondary Organic Aerosol Formation through the Epoxide Pathway at Three Urban Sites from Northern to Southern China

Isoprene is the most abundant precursor of global secondary organic aerosol (SOA). The epoxide pathway plays a critical role in isoprene SOA (iSOA) formation, in which isoprene epoxydiols (IEPOX) and/or hydroxymethyl-methyl-α-lactone (HMML) can react with nucleophilic sulfate and water producing isoprene-derived organosulfates (iOSs) and oxygen-containing tracers (iOTs), respectively.

How alkaline compounds control atmospheric aerosol particle acidity
October 15, 2021

How alkaline compounds control atmospheric aerosol particle acidity

The acidity of atmospheric particulate matter regulates its mass, composition, and toxicity and has important consequences for public health, ecosystems and climate. Despite these broad impacts, the global distribution and evolution of aerosol particle acidity are unknown.

An improved representation of fire non-methane organic gases (NMOGs) in models: emissions to reactivity
September 19, 2022

An improved representation of fire non-methane organic gases (NMOGs) in models: emissions to reactivity

Fires emit a substantial amount of non-methane organic gases (NMOGs), the atmospheric oxidation of which can contribute to ozone and secondary particulate matter formation. However, the abundance and reactivity of these fire NMOGs are uncertain and historically not well constrained. In this work, we expand the representation of fire NMOGs in a global chemical transport model, GEOS-Chem.

Total OH reactivity over the Amazon rainforest: variability with temperature, wind, rain, altitude, time of day, season, and an overall budget closure
April 26, 2021

Total OH reactivity over the Amazon rainforest: variability with temperature, wind, rain, altitude, time of day, season, and an overall budget closure

The tropical forests are Earth's largest source of biogenic volatile organic compounds (BVOCs) and thus also the largest atmospheric sink region for the hydroxyl radical (OH). However, the OH sink above tropical forests is poorly understood, as past studies have revealed large unattributed fractions of total OH reactivity.

Cryptogamic organisms are a substantial source and sink for volatile organic compounds in the Amazon region
December 21, 2021

Cryptogamic organisms are a substantial source and sink for volatile organic compounds in the Amazon region

Cryptogamic organisms such as bryophytes and lichens cover most surfaces within tropical forests, yet their impact on the emission of biogenic volatile organic compounds is unknown. These compounds can strongly influence atmospheric oxidant levels as well as secondary organic aerosol concentrations, and forest canopy leaves have been considered the dominant source of these emissions.

Ecosystem fluxes during drought and recovery in an experimental forest
December 16, 2021

Ecosystem fluxes during drought and recovery in an experimental forest

Severe droughts endanger ecosystem functioning worldwide. We investigated how drought affects carbon and water fluxes as well as soil-plant-atmosphere interactions by tracing 13CO2 and deep water 2H2O label pulses and volatile organic compounds (VOCs) in an enclosed experimental rainforest.

Measurement report: Observation-based formaldehyde production rates and their relation to OH reactivity around the Arabian Peninsula
December 1, 2021

Measurement report: Observation-based formaldehyde production rates and their relation to OH reactivity around the Arabian Peninsula

Formaldehyde (HCHO) is the most abundant aldehyde in the troposphere. While its background mixing ratio is mostly determined by the oxidation of methane, in many environments, especially in the boundary layer, HCHO can have a large variety of precursors, in particular biogenic and anthropogenic volatile organic compounds (VOCs) and their oxidation products.

Last Modified: 11.09.2024