Seasonal analysis on organic aerosol chemical composition by TD-PTR-MS at Cabauw observatory
Abstract
A ten-month observation focused on seasonal variation of chemical composition of organic aerosols (OA) were performed with a thermal-desorption proton-transfer-reaction mass spectrometer (TD-PTR-MS) as a part of the European ACTRIS-2 program in Cabauw, a rural atmospheric observation site in the western part of the Netherlands (51.971 °N, 4.927 °E). The campaign took place from December 2015 to September 2016. 686 organic ions in the range of 31-653 Da were quantified during the whole campaign and the typically observed aerosol concentrations were up to 3 ug/m3. Meteorological data such as wind speed and precipitation showed strong negative correlation to the formation of organic aerosols. In summer, oxygenated hydrocarbon compounds reached 78%-79% of the total mass concentration, while the proportion decreased to 70% in winter, indicating more oxidization processes occurred under hot weather conditions. On the contrary, pure hydrocarbon compounds had higher contribution in winter than those of summer. In autumn with a hottest week of the year included, un-oxidized nitrogen containing compounds were two times higher than other periods. High proportion of un-oxidized nitrogen containing compounds coupled with relative lower O/C ratios indicate a high primary organic aerosols (POA) contribution to the total budget. High CO concentration and high temperature detected may point to biomass burning organic aerosols (BBOA). Nitrogen containing compounds ranged from 10% to 17% in our study, while the real concentration was underestimated due to identification selectivity and the loss of nitrogen containing compounds in inorganic phases. This indicates that nitrogen plays important roles on the formation of aerosols.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.A43K3203K
- Keywords:
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- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 0320 Cloud physics and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 0368 Troposphere: constituent transport and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 3311 Clouds and aerosols;
- ATMOSPHERIC PROCESSES