Andrew Rickard

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William J Bloss

The University of Birmingham

Iain White

University of Leicester

Magda Claeys

Jean-Francois Doussin

Université Paris-Est Créteil

Hartmut Herrmann

Leibniz Institute for Tropospheric Research (IfT), Leipzig

B. Aumont

Jos Lelieveld

Max Planck Institute for Chemistry

Barbara Zielińska

Barry Lefer

University of Houston

Anne Monod

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Papers by Andrew Rickard

Distribution of gaseous and particulate organic composition during dark alpha-pinene ozonolysis

Secondary organic aerosol (SOA) affects atmospheric composition, air quality and radiative transf... more Secondary organic aerosol (SOA) affects atmospheric composition, air quality and radiative transfer. However major difficulties are encountered in the development of reliable models for SOA formation. Constraints on processes involved in SOA formation can be obtained by interpreting the speciation and evolution of organics in the gaseous and condensed phase simultaneously. In this study we investigate SOA formation from dark α-pinene ozonolysis with particular emphasis upon the mass distribution of gaseous and particulate organic species. A detailed model for SOA formation is compared with the results from experiments performed in the EUropean PHOtoREactor (EUPHORE) simulation chamber, including on-line gas-phase composition obtained from Chemical-Ionization-Reaction Time-Of-Flight Mass-Spectrometry measurements, and off-line analysis of SOA samples performed by Electrospray Ionisation Ion Trap Mass Spectrometry. The temporal profile of SOA mass concentration is relatively well reproduced by the model. Sensitivity analysis highlights the importance of the choice of vapour pressure estimation method. Comparisons of the simulated gaseous- and condensed-phase mass distributions with those observed show a generally good agreement. The simulated speciation has been used to (i) propose a chemical structure for the principal gaseous semi-volatile organic compounds and condensed monomer organic species and (ii) explore the possible contribution of a range of accretion reactions occurring in the condensed phase. We find that oligomer formation through esterification reactions gives the best agreement between the observed and simulated mass spectra.

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Insights into the Formation and Evolution of Individual Compounds in the Particulate Phase during Aromatic Photo-Oxidation

by Andrew Rickard and Amalia Munoz

Environmental science & technology, Jan 28, 2015

Secondary organic aerosol (SOA) is well-known to have adverse effects on air quality and human he... more Secondary organic aerosol (SOA) is well-known to have adverse effects on air quality and human health. However, the dynamic mechanisms occurring during SOA formation and evolution are poorly understood. The time-resolved SOA composition formed during the photo-oxidation of three aromatic compounds, methyl chavicol, toluene and 4-methyl catechol, were investigated at the European Photoreactor. SOA was collected using a particle into liquid sampler and analyzed offline using state-of-the-art mass spectrometry to produce temporal profiles of individual photo-oxidation products. In the photo-oxidation of methyl chavicol, 70 individual compounds were characterized and three distinctive temporal profile shapes were observed. The calculated mass fraction (Ci,aer/COA) of the individual SOA compounds showed either a linear trend (increasing/decreasing) or exponential decay with time. Substituted nitrophenols showed an exponential decay, with the nitro-group on the aromatic ring found to cont...

Quantifying the influence of boreal biomass burning emissions on tropospheric oxidant chemistry over the North Atlantic using BORTAS measurements

by Andrew Rickard and M. Parrington

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Aromatic Hydrocarbon Oxidation: The Contribution of Chamber Oxidation Studies

Nato Science Series: IV: Earth and Environmental Science, 2006

The Master Chemical Mechanism (http://mcm.leeds.ac.uk/MCM) has been updated to version MCMv3.1 in... more

A User-orientated Electronic Laboratory Notebook for Retrieval and Extraction of Provenance Information for EUROCHAMP-2

2011 IEEE Seventh International Conference on eScience, 2011

This research is concerned with the design and evaluation of an Electronic Laboratory Notebook (E... more This research is concerned with the design and evaluation of an Electronic Laboratory Notebook (ELN) for the simulation of chemical processes. It provides quality provenance information for scientists wishing to compare simulation runs with in vitro experimental data. The research is grounded in the EUROCHAMP-2 community. The community uses a benchmark Master Chemical Mechanism (MCM) in order to undertake their

An improved dual channel PERCA instrument for atmospheric measurements of peroxy radicals

Journal of Environmental Monitoring, 2006

This paper describes a new dual-channel PEroxy RadiCal Amplification (PERCA) instrument, which ha... more This paper describes a new dual-channel PEroxy RadiCal Amplification (PERCA) instrument, which has been designed to improve the time resolution and signal to noise and to reduce the interference caused by variations in ambient ozone concentrations. The instrument was run at the Weybourne Atmospheric Observatory (WAO), North Norfolk, during WAOWEX (Weybourne Atmospheric Observatory Winter Experiment) in January/February 2002 and INSPECTRO (Influence of clouds on the spectral actinic flux in the lower troposphere) in September 2002. The performance of the instrument is assessed and compared to that of a single channel instrument. In particular, it is shown how the precision is greatly improved in fluctuating background ozone conditions. In addition the improved time response of the instrument allows changes in peroxy radical concentrations to be related to rapid changes in nitric oxide concentrations and the ozone photolysis frequency, j(O(1)D).

Architecture design of a user-orientated electronic laboratory notebook: A case study within an atmospheric chemistry community

Future Generation Computer Systems, 2013

ABSTRACT Data is particularly valuable to scientists when details of its provenance are known. Th... more ABSTRACT Data is particularly valuable to scientists when details of its provenance are known. This research concerned deploying a user-orientated electronic laboratory notebook (ELN) system within a scientific community. The ELN system supported the capture and retrieval of semantic metadata describing the provenance of the modelling activities of scientists within that community. The research was grounded within the atmospheric chemistry community but has applicability to other communities using an iterative model development process. The ELN system involved the automatic capture of metadata concerning the modelling process together with inline annotations added by the modeller explaining the reasoning for modelling decisions at each step of the process. A full realisation of the ELN system was built and evaluated by members of the atmospheric chemistry community. In order to promote reusability the ELN system architecture had domain-independent as well as domain-dependent elements. An ontology (in OWL) was used to ensure that the specific terminology of the community was used within the provenance metadata and also that it was used consistently. Other domain-independent elements of the architecture included a dynamic graphic interface that allowed the modeller to view his/her modelling history. This was recorded as a set of nodes each pointing to the stored provenance metadata associated with a specific simulation run. In addition, there was an innovative mechanism that enabled the modeller to navigate through the various nodes. The navigation process supported making comparisons between different nodes: a facility that users found particularly valuable. Members of the atmospheric chemistry community took part in a two-day summative evaluation of the ELN system. This confirmed its value to the modellers and it is now being introduced more widely across the modelling community. In addition, the research proposes a methodology for transferring this ELN system to other modelling communities making use of the domain-independent elements of the architecture.

Ozone photochemistry in boreal biomass burning plumes

by Andrew Rickard, M. Parrington, and J. Hopkins

Atmospheric Chemistry and Physics, 2013

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Radical Yields from the Ozonolysis of Small (C2-C6) Alkenes

Unsaturated VOCs, alkenes, are emitted to the atmosphere from a wide range of anthropogenic and n... more Unsaturated VOCs, alkenes, are emitted to the atmosphere from a wide range of anthropogenic and natural sources. They are significant primary pollutants in the boundary layer, contributing to total VOC emissions in urban air, where they may account for up to 30% of the total OH sink, however a key fate for alkenes is reaction with ozone, which may form

Quantifying the impact of BOReal forest fires on Tropospheric oxidants over the Atlantic using Aircraft and Satellites (BORTAS) experiment: Design, execution and science overview

by M. Parrington, Andrew Rickard, J. Hopkins, Grant Forster, S. O'Shea, and R. Purvis

Atmospheric Chemistry and Physics, 2013

ABSTRACT We describe the design and execution of the BORTAS (Quantifying the impact of BOReal for... more ABSTRACT We describe the design and execution of the BORTAS (Quantifying the impact of BOReal forest fires on Tropospheric oxidants using Aircraft and Satellites) experiment, which has the overarching objective of understanding the chemical aging of airmasses, containing the emission products from seasonal boreal wildfires, and how they impact downwind atmospheric composition. The central focus of the experiment was a two-week deployment of the UK BAe-146-301 Atmospheric Research Aircraft (ARA) over eastern Canada. This was complemented by ground-based measurements at the Dalhousie University Ground Station (DGS) and the University of Toronto, enhanced ozonesonde launches, measurements on the Pico Mountain Atmospheric Observatory in the Azores, and coordinated space-borne measurements. Integration of these data has helped us to describe pollution plumes from wildfires on a wide spectrum of temporal and spatial scales. These data are interpreted using a range of chemistry models, from a near-explicit gas-phase chemical mechanism to a regional and global model of atmospheric transport and lumped chemistry, and data assimilation tools. We also provide a brief science overview of the project, providing the platform for co-submitted science abstracts.

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Online and offline mass spectrometric study of the impact of oxidation and ageing on glyoxal chemistry and uptake onto ammonium sulfate aerosols

by Andrew Rickard, Robert M Healy, and Emanuela Finessi

Faraday Discussions, 2013

Recent laboratory and modelling studies have shown that reactive uptake of low molecular weight a... more Recent laboratory and modelling studies have shown that reactive uptake of low molecular weight alpha-dicarbonyls such as glyoxal (GLY) by aerosols is a potentially significant source of secondary organic aerosol (SOA). However, previous studies disagree in the magnitude of the uptake of GLY, the mechanism involved and the physicochemical factors affecting particle formation. In this study, the chemistry of GLY with ammonium sulfate (AS) in both bulk laboratory solutions and in aerosol particles is investigated. For the first time, Aerosol Time of Flight Mass Spectrometry (ATOFMS), a single particle technique, is used together with offline (ESI-MS and LC-MS2) mass spectrometric techniques to investigate the change in composition of bulk solutions of GLY and AS resulting from aqueous photooxidation by OH and from ageing of the solutions in the dark. The mass spectral ions obtained in these laboratory studies were used as tracers of GLY uptake and chemistry in AS seed particles in a series of experiments carried out under dark and natural irradiated conditions at the outdoor European Photo-reactor (EUPHORE). Glyoxal oligomers formed were not detected by the ATOFMS, perhaps due to inefficient absorption at the laser wavelength. However, the presence of organic nitrogen compounds, formed by reaction of GLY with ammonia was confirmed, resulting in an increase in the absorption efficiency of the aerosol, and this increased the number of particles successfully ionised by the ATOFMS. A number of light absorbing organic nitrogen species, including 1H-imidazole, 1H-imidazole-2-carboxaldehyde, 2,2&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;-bis-imidazole and a glyoxal substituted 2,2&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;-bisimidazole, previously identified in aqueous laboratory solutions, were also identified in chamber aerosol and formed on atmospherically relevant timescales. An additional compound, predicted to be 1,2,5-oxadiazole, had an enhanced formation rate when the chamber was open and is predicted to be formed via a light activated pathway involving radical oxidation of ammonia to hydroxylamine, followed by subsequent reaction with glyoxal to form an intermediate glyoxime.

Distribution of gaseous and particulate organic composition during dark alpha-pinene ozonolysis

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Insights into the Formation and Evolution of Individual Compounds in the Particulate Phase during Aromatic Photo-Oxidation

by Andrew Rickard and Amalia Munoz

Environmental science & technology, Jan 28, 2015