Abstract. A total of 10 years of hourly aerosol and gas data at four rural German stations have been combined with
hourly back trajectories to the stations and inventories of the European Emissions Database for Global
Atmospheric Research (EDGAR),
yielding pollution maps over Germany of PM10, particle number concentrations, and
equivalent black carbon (eBC). The maps reflect aerosol emissions modified with atmospheric
processes during transport between sources and receptor sites. Compared to emission maps, strong
western European emission centers do not dominate the downwind concentrations because their
emissions are reduced by atmospheric processes on the way to the receptor area. PM10,
eBC, and to some extent also particle number concentrations are rather controlled by emissions
from southeastern Europe from which pollution transport often occurs under drier conditions. Newly
formed particles are found in air masses from a broad sector reaching from southern Germany to
western Europe, which we explain with gaseous particle precursors coming with little wet scavenging
from this region. Annual emissions for 2009 of PM10, BC, SO2, and NOx were
accumulated along each trajectory and compared with the corresponding measured time series. The
agreement of each pair of time series was optimized by varying monthly factors and annual factors
on the 2009 emissions. This approach yielded broader summer emission minima than published values
that were partly displaced from the midsummer positions. The validity of connecting the ambient concentration and
emission of particulate pollution was tested by calculating temporal changes in eBC for subsets of
back trajectories passing over two separate prominent emission regions, region A to the northwest
and B to the southeast of the measuring stations. Consistent with reported emission data the
calculated emission decreases over region A are significantly stronger than over region B.