Modeling exceptional high concentrations of carbonaceous aerosols observed at Pic du Midi in spring–summer 2003: Comparison with Sonnblick and Puy de Dôme

Carbonaceous aerosols have been sampled weekly in 2002 and 2003 at Pic du Midi (PdMO), an isolated high-altitude Pyrenean station. High concentrations of both black carbon (BC) and total organic carbon (OC) have been observed during the exceptional prolonged warm dry spell over western Europe in spring–summer 2003, culminating during the first 2 weeks in August. The aerosol ORISAM-TM4 global model [Guillaume, B., Liousse, C., Rosset, R., Cachier, H., Van Velthoven, P., Bessagnet, B., Poisson, N., 2007. ORISAM-TM4: a new global sectional multi-component aerosol model including SOA formation—focus on carbonaceous BC and OC aerosols. Tellus B 59, 283–302.], together with new updated European emission inventories, appears apt to closely simulate at this PdMO site the BC and OC aerosol components during the whole 2002–2003 period, including the August 2003 heat wave. Further, ORISAM-TM4 provides unique detailed information on both primary and secondary OC fractions together with differentiated aerosol secondary anthropogenic (SOAA) vs. biogenic OC (SOAB) contributions, not accessible to measurements. Such comparisons have been extended to two other high-altitude European sites of the CARBOSOL programme, Sonnblick (Austrian Alps) and Puy de Dôme (central France). At these two sites, the agreement between simulations and measured values is clearly not so close as at PdMO, with systematic more elevated measured values of both BC and OC, presumably due to local and regional sources.