Evaluation of isoprene degradation in the detailed tropospheric chemical mechanism, MCM v3, using environmental chamber data

Pinho, Paulo; Pio, Casimiro; Jenkin, Michael E.

doi:10.1016/j.atmosenv.2004.11.014

Cited by 55 publications

(48 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…To varying extents, such mechanisms also incorporate strategic simplifications to limit their overall size, which would otherwise include as many as 10 5 −10 6 reactions. The performance of these gas-phase mechanisms can be tested (and, if necessary, refined) using chamber data (e.g., Carter, 2000;Pinho et al, 2005Pinho et al, , 2006Pinho et al, , 2007. Such procedures have traditionally been focused on providing validated descriptions of ozone formation from the photooxidation of VOC/NO x mixtures, although the development of highly-instrumented chambers (see Table 2 in Sect.…”

Section: Generation Of Atmospheric Degradation Mechanisms For Vocsmentioning

confidence: 99%

The formation, properties and impact of secondary organic aerosol: current and emerging issues

et al. 2009

View full text Add to dashboard Cite

Abstract. Secondary organic aerosol (SOA) accounts for a significant fraction of ambient tropospheric aerosol and a detailed knowledge of the formation, properties and transformation of SOA is therefore required to evaluate its impact on atmospheric processes, climate and human health. The chemical and physical processes associated with SOA formation are complex and varied, and, despite considerable progress in recent years, a quantitative and predictive understanding of SOA formation does not exist and therefore represents a major research challenge in atmospheric science. This review begins with an update on the current state of knowledge on the global SOA budget and is followed by an overview of the atmospheric degradation mechanisms for SOA precursors, gas-particle partitioning theory and the analytical techniques used to determine the chemical composition of SOA. A survey of recent laboratory, field and modeling studies is also presented. The following topical and emerging issues are highlighted and discussed in detail: molecular characterization of biogenic SOA constituents, condensed phase reactions and oligomerization, the interaction of atmospheric organic components with sulfuric acid, the chemical and photochemical processing of organics in the atmospheric aqueous phase, aerosol formation from real plant emissions, interaction of atmospheric organic components with water, thermodynamics and mixtures in atmospheric models. Finally, the major challenges ahead in laboratory, field and modeling studies of SOA are discussed and recommendations for future research directions are proposed.

show abstract

Section: Generation Of Atmospheric Degradation Mechanisms For Vocsmentioning

confidence: 99%

The formation, properties and impact of secondary organic aerosol: current and emerging issues

et al. 2009

View full text Add to dashboard Cite

show abstract

“…While MEK mixing ratios in our study are relatively constant, MEK has been measured in many different ecosystems ranging from 0.073 ppb to 4 ppb. Therefore, it is important to consider the variability in this compound as MEK can lead to PAN and ozone formation in the atmosphere (Pinho et al, 2005). Photochemical odd-hydrogen production in the upper troposphere (Atkinson, 2000;Baeza Romero et al, 2005;De Gouw et al, 1999) can further enhance the MEK ozone forming potential (Folkins et al, 1998;Prather and Jacob, 1997).…”

Section: Remarks and Conclusionmentioning

confidence: 99%

“…The atmospheric degradation of MEK leads to acetaldehyde and formaldehyde formation. In the presence of NO x , MEK can lead to peroxyacetyl nitrate (PAN) and ozone formation (Grosjean et al, 2002;Pinho et al, 2005). In the upper troposphere, MEK photolyses and regenerates OH (Atkinson, 2000;Baeza Romero et al, 2005;De Gouw et al, 1999), as does acetone, potentially increasing ozone formation.…”

Section: Introductionmentioning

confidence: 99%

Atmospheric mixing ratios of methyl ethyl ketone (2-butanone) in tropical, boreal, temperate and marine environments

et al. 2016

View full text Add to dashboard Cite

Abstract. Methyl ethyl ketone (MEK) enters the atmosphere following direct emission from vegetation and anthropogenic activities, as well as being produced by the gas-phase oxidation of volatile organic compounds (VOCs) such as nbutane. This study presents the first overview of ambient MEK measurements at six different locations, characteristic of forested, urban and marine environments. In order to understand better the occurrence and behaviour of MEK in the atmosphere, we analyse diel cycles of MEK mixing ratios, vertical profiles, ecosystem flux data, and HYSPLIT back trajectories, and compare with co-measured VOCs. MEK measurements were primarily conducted with protontransfer-reaction mass spectrometer (PTR-MS) instruments. Results from the sites under biogenic influence demonstrate that vegetation is an important source of MEK. The diel cycle of MEK follows that of ambient temperature and the forest structure plays an important role in air mixing. At such sites, a high correlation of MEK with acetone was observed (e.g. r 2 = 0.96 for the SMEAR Estonia site in a remote hemiboreal forest in Tartumaa, Estonia, and r 2 = 0.89 at the ATTO pristine tropical rainforest site in central Amazonia). Under polluted conditions, we observed strongly enhanced MEK mixing ratios. Overall, the MEK mixing ratios and flux data presented here indicate that both biogenic and anthropogenic sources contribute to its occurrence in the global atmosphere.

show abstract

“…Ecosystemscale fluxes of VOCs were calculated based on concentration gradients throughout the canopy and applying an Inverse Lagrangian Transport Model (Raupach, 1989, Nemitz et al, 2000, and Karl et al, 2004. The VOC fluxes were computed according to The parameterization of D was based on turbulence measurements inside and above the canopy and calculated using the far-and near-field approach described by Raupach (1989).…”

Section: Voc Gradient Fluxesmentioning

confidence: 99%

“…Brasseur et al, 1998;Bey et al, 2001;Kuhlmann et al, 2003) to simulate the tropical photo-reactor and assess how the oxidizing capacity of the remote tropical atmosphere is modulated by this compound. Isoprene chemistry schemes (Fan and Zhang, 2004;Carter and Atkinson, 1996;Pinho et al, 2005) are typically condensed so they can be incorporated in global and regional chemistry models. Most current lumped chemistry schemes include near explicit representation of the first and second generation oxidation products of isoprene (Emmons et al, 2009;Taraborelli et al, 2008;Emmerson and Evans, 2009).…”

Section: Introductionmentioning

confidence: 99%

Rapid formation of isoprene photo-oxidation products observed in Amazonia

et al. 2009

View full text Add to dashboard Cite

Abstract. Isoprene represents the single most important reactive hydrocarbon for atmospheric chemistry in the tropical atmosphere. It plays a central role in global and regional atmospheric chemistry and possible climate feedbacks. Photooxidation of primary hydrocarbons (e.g. isoprene) leads to the formation of oxygenated VOCs (OVOCs). The evolution of these intermediates affects the oxidative capacity of the atmosphere (by reacting with OH) and can contribute to secondary aerosol formation, a poorly understood process. An accurate and quantitative understanding of VOC oxidation processes is needed for model simulations of regional air quality and global climate. Based on field measurements conducted during the Amazonian Aerosol Characterization Experiment (AMAZE-08) we show that the production of certain OVOCs (e.g. hydroxyacetone) from isoprene photooxidation in the lower atmosphere is significantly underpredicted by standard chemistry schemes. Recently reported fast secondary production could explain 50% of the observed discrepancy with the remaining part possibly produced via a novel primary production channel, which has been proposed theoretically. The observations of OVOCs are also used to test a recently proposed HO x recycling mechanism via degradation of isoprene peroxy radicals. If generalized our observations suggest that prompt photochemical formation of OVOCs and other uncertainties in VOC oxidation schemes could result in uncertainties of modelled OH reactivity, potentially explaining a fraction of the missing OH sink over forests which has previously been largely attributed to a missing source of primary biogenic VOCs.

show abstract

Evaluation of isoprene degradation in the detailed tropospheric chemical mechanism, MCM v3, using environmental chamber data

Cited by 55 publications

References 26 publications

The formation, properties and impact of secondary organic aerosol: current and emerging issues

The formation, properties and impact of secondary organic aerosol: current and emerging issues

Atmospheric mixing ratios of methyl ethyl ketone (2-butanone) in tropical, boreal, temperate and marine environments

Rapid formation of isoprene photo-oxidation products observed in Amazonia

Contact Info

Product

Resources

About