Seasonal characteristics of the physicochemical properties of North Atlantic marine atmospheric aerosols

• Published in: Journal of Geophysical Research
• Main Authors: Yoon, Y. J., Ceburnis, D., Cavalli, F., Jourdan, O., Putaud, J., Facchini, M., Decesari, S., Fuzzi, S., Sellegri, K., Jennings, S. G., O'Dowd, C. D.
• Other Authors: National University of Ireland Galway (NUI Galway), Korea Polar Research Institute (KOPRI), JRC Institute for Environment and Sustainability (IES), European Commission - Joint Research Centre Ispra (JRC), Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne 2017-2020 (UCA 2017-2020 )-Centre National de la Recherche Scientifique (CNRS), Istituto di Scienze dell'Atmosfera e del Clima Bologna (ISAC), Consiglio Nazionale delle Ricerche (CNR)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2007
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology; Aitken; North Atlantic
• Online Access: https://hal.science/hal-01982563; https://hal.science/hal-01982563/document; https://hal.science/hal-01982563/file/2005JD007044_Published.pdf; https://doi.org/10.1029/2005jd007044

International audience The aerosol size distribution modal diameters show seasonal variations, 0.031 mm in winter and 0.049 mm in summer for the Aitken mode and 0.103 mm in winter and 0.177 mm in summer for the accumulation mode. The accumulation mode mass also showed a seasonal variation, minimum in winter and maximum in summer. A supermicron sized particle mode was found at 2 mm for all seasons showing 30% higher mass concentration during winter than summer resulting from higher wind speed conditions. Chemical analysis showed that the concentration of sea salt has a seasonal pattern, minimum in summer and maximum in winter because of a dependency of sea-salt load on wind speeds. By contrast, the non-sea-salt (nss) sulphate concentration in fine mode particles exhibited lower values during winter and higher values during midsummer. The water soluble organic carbon (WSOC) and total carbon (TC) analysis also showed a distinctive seasonal pattern. The WSOC concentration during the high biological activity period peaked at 0.2 mgC m À3 , while it was lower than 0.05 mgC m À3 during the low biological activity period. The aerosol light scattering coefficient showed a minimum value of 5.5 Mm À1 in August and a maximum of 21 Mm À1 in February. This seasonal variation was due to the higher contribution of sea salt in the MBL during North Atlantic winter. By contrast, aerosols during late spring and summer exhibited larger angstrom parameters than winter, indicating a large contribution of the biogenically driven fine or accumulation modes. Seasonal characteristics of North Atlantic marine aerosols suggest an important link between marine aerosols and biological activity through primary production of marine aerosols.