English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

High-resolution aerosol mass spectrometer measurements were performed,for the first time, at the Mt. Cimone Global Atmosphere Watch (GAW) stationbetween June and July 2012, within the EU project PEGASOS and theARPA–Emilia-Romagna project SUPERSITO. Submicron aerosol was dominated byorganics (63 %), with sulfate, ammonium and nitrate contributing theremaining 20, 9 and 7 %, respectively. Organic aerosol (OA) was ingeneral highly oxygenated, consistent with the remote character of the site;our observations suggest that oxidation and secondary organic aerosol (SOA)formation processes occurred during aerosol transport to high altitudes. Allof the aerosol component concentrations as well as the OA elemental ratiosshowed a clear daily trend, driven by the evolution of the planetaryboundary layer (PBL) and by the mountain wind regime. Higher loadings andlower OA oxidation levels were observed during the day, when the site waswithin the PBL, and therefore affected by relatively fresh aerosoltransported from lower altitudes. Conversely, lower loadings and higher OAoxidation levels were observed at night, when the top of Mt. Cimone residedin the free troposphere although affected by the transport of residuallayers on several days of the campaign. Analysis of the elemental ratios ina Van Krevelen space shows that OA oxidation follows a slope comprisedbetween −0.5 and −1, consistent with addition of carboxylic groups, with orwithout fragmentation of the parent molecules. The increase of carboxylicgroups during OA ageing is confirmed by the increased contribution oforganic fragments containing more than one oxygen atom in the freetroposphere night-time mass spectra. Finally, positive matrix factorizationwas able to deconvolve the contributions of relatively fresh OA (OOAa)originating from the PBL, more aged OA (OOAb) present at high altitudesduring periods of atmospheric stagnation, and very aged aerosols (OOAc)transported over long distances in the free troposphere

Organic aerosol evolution and transport observed at Mt. Cimone (2165 m a.s.l.), Italy, during the PEGASOS campaign