Publications related to Extreme events in total ozone over Arosa---Part 2: Fingerprints of atmospheric dynamics and chemistry and effects on mean values and long-term changes

Nanocluster Aerosols from Ozone-Human Chemistry Are Dominated by Squalene-Ozone Reactions

Dusan Licina, Shen Yang

Nanocluster aerosols (NCAs,

Amer Chemical Soc2024

Nanocluster aerosol formation via ozone chemistry on worn clothing: Influence of environmental parameters

Dusan Licina, Shen Yang

Nanocluster aerosols (NCA, particles

Pergamon-Elsevier Science Ltd2024

Influence of Ventilation on Formation and Growth of 1-20 nm Particles via Ozone-Human Chemistry

Dusan Licina, Shen Yang, Marouane Merizak, Meixia Zhang

Ozone reaction with human surfaces is an important source of ultrafine particles indoors. However, 1-20 nm particles generated from ozone-human chemistry, which mark the first step of particle formation and growth, remain understudied. Ventilation and indo ...

Amer Chemical Soc2024

Squalene Depletion in Skin Following Human Exposure to Ozone under Controlled Chamber Conditions

Shen Yang

A major component of human skin oil is squalene, a highly unsaturated hydrocarbon that protects the skin from atmospheric oxidants. Skin oil, and thus squalene, is continuously replenished on the skin surface. Squalene is also quickly consumed through reac ...

Amer Chemical Soc2024

Modelling the coupled mercury-halogen-ozone cycle in the central Arctic during spring

Jenny Thomas, Julia Schmale, Ivo Fabio Beck, Hélène Paule Angot

Near-surface mercury and ozone depletion events occur in the lowest part of the atmosphere during Arctic spring. Mercury depletion is the first step in a process that transforms long-lived elemental mercury to more reactive forms within the Arctic that are ...

2023

Nitrogen oxides in the free troposphere: implications for tropospheric oxidants and the interpretation of satellite NO2 measurements

Ilann Ernest Valentin Bourgeois

Satellite-based retrievals of tropospheric NO(2)columns are widely used to infer NOx (equivalent to NO + NO2) emissions. These retrievals rely on model information for the vertical distribution of NO2. The free tropospheric background above 2 km is particu ...

Copernicus GmbH2023

Arctic tropospheric ozone: assessment of current knowledge and model performance

Luca Pozzoli, Jakob Boyd Pernov, Ilann Ernest Valentin Bourgeois

As the third most important greenhouse gas (GHG) after carbon dioxide (CO2) and methane (CH4), tropospheric ozone (O3) is also an air pollutant causing damage to human health and ecosystems. This study brings together recent research on observations and mo ...

Copernicus Publications2023

Critical Review on Bromate Formation during Ozonation and Control Options for Its Minimization

Urs von Gunten

Ozone is a commonly applied disinfectant and oxidantin drinkingwater and has more recently been implemented for enhanced municipalwastewater treatment for potable reuse and ecosystem protection. Onedrawback is the potential formation of bromate, a possible ...

AMER CHEMICAL SOC2023

Evaluation of the role of superoxide radical as chain carrier for the formation of hydroxyl radical during ozonation

Gang Yu, Urs von Gunten, Yan Wang

Superoxide radicals (O-2(center dot-)) have been suggested as an important chain carrier in the radical chain reaction that promotes ozone (O-3) decomposition to hydroxyl radicals ((OH)-O-center dot) during ozonation. However, due to the difficulty in meas ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Widespread detection of chlorine oxyacids in the Arctic atmosphere

Julia Schmale, Ivo Fabio Beck, Hélène Paule Angot

Observations are reported of HClO3 and HClO4 in the atmosphere and their widespread occurrence over the pan-Arctic during spring, providing further insights into atmospheric chlorine cycling in the polar environment. ...

Nature Portfolio2023

Low ozone dry deposition rates to sea ice during the MOSAiC field campaign: Implications for the Arctic boundary layer ozone budget

Julia Schmale, Ivo Fabio Beck, Hélène Paule Angot

Dry deposition to the surface is one of the main removal pathways of tropospheric ozone (O3). We quantified for the first time the impact of O3 deposition to the Arctic sea ice on the planetary boundary layer (PBL) O3 concentration and budget using year-ro ...

2023

Substantial contribution of iodine to Arctic ozone destruction

Julia Schmale, Ivo Fabio Beck, Lubna Dada, Hélène Paule Angot

Unlike bromine, the effect of iodine chemistry on the Arctic surface ozone budget is poorly constrained. We present ship-based measurements of halogen oxides in the high Arctic boundary layer from the sunlit period of March to October 2020 and show that io ...

2022

Key challenges for tropospheric chemistry in the Southern Hemisphere

Julia Schmale

This commentary paper from the recently formed International Global Atmospheric Chemistry (IGAC) Southern Hemisphere Working Group outlines key issues in atmospheric composition research that particularly impact the Southern Hemisphere. In this article, we ...

2022

Exploring the link between austral stratospheric polar vortex anomalies and surface climate in chemistry-climate models

Nora Bergner

Extreme events in the stratospheric polar vortex can lead to changes in the tropospheric circulation and impact the surface climate on a wide range of timescales. The austral stratospheric vortex shows its largest variability in spring, and a weakened pola ...

Copernicus GmbH2022

Synthetic chemistry with nitrous oxide and triazenes

Iris Roswitha Landman

Nitrous oxide (N2O) has gained much interest because of its physiological effects ("laughing gas") and its negative environmental impact ("greenhouse gas", "ozone-depleting substance"): It has a lifetime of more than 100 years in the atmosphere. Its persis ...

EPFL2022

Ozonation of organic compounds in water and wastewater: A critical review

Urs von Gunten, Sung Eun Lim

Ozonation has been applied in water treatment for more than a century, first for disinfection, later for oxidation of inorganic and organic pollutants. In recent years, ozone has been increasingly applied for enhanced municipal wastewater treatment for eco ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Application of UV absorbance and electron-donating capacity as surrogates for micropollutant abatement during full-scale ozonation of secondary-treated wastewater

Urs von Gunten

Ozonation of secondary-treated wastewater for the abatement of micropollutants requires a reliable control of ozone doses. Changes in the UV absorbance of dissolved organic matter (DOM) during ozonation allow to estimate micropollutant abatement on-line an ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Optical properties and photochemical production of hydroxyl radical and singlet oxygen after ozonation of dissolved organic matter

Frank Jonathan Leresche, Urs von Gunten

This study focuses on the effects of ozonation on the optical and photochemical properties of dissolved organic matter (DOM). Upon ozonation, a decrease in light absorption properties of DOM was observed concomitantly with a large increase in singlet oxyge ...

ROYAL SOC CHEMISTRY2021

Ozone Initiates Human-Derived Emission of Nanocluster Aerosols

Dusan Licina, Shen Yang

Nanocluster aerosols (NCAs, particles

AMER CHEMICAL SOC2021

Ozone concentration measured during the Arctic Ocean 2018 expedition

Julia Schmale, Andrea Baccarini

Ozone was measured with a 2B Technology ozone monitor (model 205). The concentration is reported as a mixing ratio in parts per billion [ppb], at 60 seconds average. Ozone is a trace gas that can be formed directly in the troposphere (the most important fo ...

2020