0000000000535807

AUTHOR

C. O'dowd

showing 2 related works from this author

Characterization of the light-absorbing properties, chromophore composition and sources of brown carbon aerosol in Xi'an, northwestern China

2020

The impact of brown carbon aerosol (BrC) on the Earth's radiative forcing balance has been widely recognized but remains uncertain, mainly because the relationships among BrC sources, chromophores and optical properties of aerosol are poorly understood. In this work, the light absorption properties and chromophore composition of BrC were investigated for samples collected in Xi'an, northwestern China, from 2015 to 2016. Both absorption Ångström exponent (AAE) and mass absorption efficiency (MAE) show distinct seasonal differences, which could be attributed to the differences in sources and chromophore composition of BrC. Three groups of light-absorbing organics were found to be important Br…

Total organic carbonAtmospheric Science010504 meteorology & atmospheric sciencesAnalytical chemistrychemistry.chemical_elementCoal combustion products010501 environmental sciencesChromophoreRadiative forcing01 natural scienceslcsh:QC1-999Aerosollcsh:Chemistrychemistrylcsh:QD1-999Absorption (electromagnetic radiation)CarbonMass fractionlcsh:Physics0105 earth and related environmental sciencesAtmospheric Chemistry and Physics
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Summertime and wintertime atmospheric processes of secondary aerosol in Beijing

2020

Secondary aerosol constitutes a large fraction of fine particles in urban air of China. However, its formation mechanisms and atmospheric processes remain largely uncertain despite considerable study in recent years. To elucidate the seasonal variations in fine-particle composition and secondary aerosol formation, an Aerodyne quadrupole aerosol chemical speciation monitor (Q-ACSM), combined with other online instruments, was used to characterize the sub-micrometer particulate matter (diameter < 1 µm, PM1) in Beijing during summer and winter 2015. Our results suggest that photochemical oxidation was the major pathway for sulfate formation during summer, whereas aqueou…

Atmospheric Science010504 meteorology & atmospheric sciences010501 environmental sciencesParticulates01 natural scienceslcsh:QC1-999Aerosollcsh:Chemistrychemistry.chemical_compoundNitratechemistrylcsh:QD1-999Liquid water contentTRACEREnvironmental chemistryEnvironmental scienceRelative humidityComposition (visual arts)Sulfatelcsh:Physics0105 earth and related environmental sciencesAtmospheric Chemistry and Physics
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