TRAQA

Proposed objectives

1- Characterisation of the dynamic processes of export of polluted air masses from the source regions of the basin

2- Quantification of exchanges between the boundary layer and the free troposphere

3- Lagrangian monitoring of the aging and mixing of pollution plumes in the lower troposphere

4- Analysis of the representativeness of the study cases over a longer period of time.

The TRAQA experiment was carried out by triggering intensive observation periods (POIs) on alert when conditions were favourable. A total of 7 POIs were conducted with nearly 60 h of aircraft flights and 5 boundary layer balloon flights. Thus, we documented a pollution episode in the Gulf of Genoa, an established moderate Mistral case, an extreme case of African dust, a case of pollution export from Barcelona to the Mediterranean Sea, and a case of Mistral departure. The remaining two OPIs, conducted under classical summer anticyclonic conditions, were devoted to airborne measurements of biogenic emissions from Mediterranean vegetation, and to regional documentation of the main sources of anthropogenic pollution on the northern Mediterranean coast.