Dynamics and impact of marine bioaerosols are still poorly understood. The sojourn time of airborne microorganisms can last to several days, so even transcontinental transport is likely to occur. Only little is known about bacterial communities of marine bioaerosol in terms of diversity community composition. Few recent studies showed that bioaerosols often exhibited a similar bacterial community as the subjacent ecosystems. We combined two different sampling strategies in our recent investigation. In order to elucidate the spatial variation, 36 samples were gathered during a ship cruise from the North Sea to the Baltic Sea in August 2011 using an impingement sampler (XMX/2L-MIL, Dycor, Canada). Furthermore, a one year survey is conducted to investigate temporal variation of bioaerosols at the offshore island Helgoland (German Bight, North Sea). The s amples were analysed with culture independent molecular methods. Quantification was carried out using q-PCR and C-FLAPS analysis. The community structure was analysed with ARISA-fingerprints. Phylogenetic analysis was performed via 454 16S tag-sequencing. First results showed high variation in spatial distributions, concerning the concentration of airborne bacteria, ranging from 10² to 105 cells per m-³. This is probably explained by the origin of sampled air parcels, correlated to the calculated backward trajectories, which also showed high variation. These results will be integrated within the context of the 454 sequencing data. Furthermore, results of the temporal aspect will be shown for the first time.