Non-Methane Volatile Organic Compounds in the Background Atmospheres of a Southern European Mountain Site (Mt. Cimone, Italy): Annual and Seasonal Variability
| Autor: | Michela Maione, F. Furlani, Martin L. Williams, Paolo Cristofanelli, Umberto Giostra, Jgor Arduini, Eleonora Lo Vullo |
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| Rok vydání: | 2016 |
| Předmět: |
Long-term observations
010504 meteorology & atmospheric sciences Range (biology) Air pollution 010501 environmental sciences medicine.disease_cause 01 natural sciences Pollution Mediterranean Basin Methane olatile hydrocarbons chemistry.chemical_compound chemistry Air quality Hydroxyl radical 13. Climate action Climatology medicine Environmental Chemistry Environmental science Seasonal cycle Air quality index 0105 earth and related environmental sciences |
| Zdroj: | Aerosol and Air Quality Research |
| ISSN: | 2071-1409 1680-8584 |
| DOI: | 10.4209/aaqr.2015.05.0364 |
| Popis: | Since January 2010 continuous high-frequency in situ measurements of a range of anthropogenic Non-Methane Volatile Organic Compounds (NMVOCs) has been carried out at the World Meteorological Organisation Global Atmospheric Watch observatory at Mt. Cimone, on the highest peak of the Italian Northern Apennines, at the border between the Po Valley and the Mediterranean Basin. Five-year (2010-2014) time series of eleven NMVOCs, including aromatic and aliphatic species, have been analysed in order to derive average mixing ratios and detect annual and seasonal variability. Recent studies conducted in Europe, mainly in urban areas, have reported a decrease in atmospheric NMVOCs. Here we investigate how the decline in emissions, due to the implementation of air pollution policies, is reflected in the annual variability of NMVOC mixing ratios measured at a regional background location. Analysis of temporal trends for wellmixed conditions showed statistically significant decreases in ethyne, n-pentane and ethyl-benzene, while no significant trends were found for propane, butanes, i-pentane, toluene and xylenes. The seasonal variability of NMVOCs has been studied showing clear seasonal cycles for longer lived compounds and cycles with smaller seasonal amplitudes for shorterlived species. We used the propane time series to describe the seasonal cycle and to verify to what extent the mixing ratios of propane have been depleted by OH oxidation. We found that, during the summer, different transport times to the receptors and different source distribution are the main responsible for the relatively low integrated OH concentrations at Mt. Cimone. |
| Databáze: | OpenAIRE |
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