TRACING OF ATMOSPHERIC AEROSOL SOURCES USING STABLE CARBON ISOTOPES

The identification of the pollution sources of incoming carbonaceous aerosols (total aerosol mass and PM2.5) at the Preila environment background station (Lithuania) during a winter period (2008) using the stable carbon isotope ratio delta C-13 is presented. For air mass transport analysis the Hybrid Single-Particle Lagrangian Integrated Trajectories (HYSPLIT) model was used. During the experiment the aerosol carbon isotopic ratio delta C-13 ranged from -24.0 +/- 0.1 to -30.9 +/- 0.2 parts per thousand. The measurement data of the total aerosol mass particle delta C-13 values had not shown a significant variation and did not depend on the air mass transport directions. The mean delta C-13 value of these aerosol particles was -25.5 +/- 0.7 parts per thousand. It can be attributed to the local aerosol particle origin and it is of the same order as that of marine aerosol PM2.5 delta C-13 values, The delta C-13 values for the aerosol particles PM2.5 transported from longer distances depended on the air mass transport directions. The mean value of delta C-13 (-30.9 +/- 0.2 parts per thousand) of aerosol particles in the continental air masses of the eastern direction was lower than that of aerosol particles in relatively clear marine air masses of the western direction (-24.0 +/- 0.1 to -25.4 +/- 0.3 parts per thousand). In the cases of other air mass transport events, samples (PM2.5) Collected at the Preila site were a mix of aerosol particles from the marine environment and anthropogenic (fossil fuel combustion products) pollution sources.