Abstract. Aerosol and rain sampling in two size fractions was carried out at a rural site located
on the coast of the eastern Mediterranean, Erdemli, Turkey
(36∘33′54′′ N, 34∘15′18′′ E). A total of 674
aerosol samples in two size fractions (337 coarse, 337 fine) and 23
rain samples were collected between March 2014 and April 2015. Samples were
analyzed for NO3-, NH4+ and ancillary water-soluble ions
using ion chromatography and water-soluble total nitrogen (WSTN) by applying a
high-temperature combustion method. The mean aerosol water-soluble organic nitrogen (WSON) was
23.8 ± 16.3 nmol N m−3, reaching a maximum of
79 nmol N m−3, with about 66 % being associated with coarse
particles. The volume weighted mean (VWM) concentration of WSON in rain was
21.5 µmol N L−1. The WSON contributed 37 and 29 % to the
WSTN in aerosol and rainwater, respectively. Aerosol WSON concentrations
exhibited large temporal variation, mainly due to meteorology and the origin
of air mass flow. The highest mean aerosol WSON concentration was observed in
the summer and was attributed to the absence of rain and resuspension of
cultivated soil in the region. The mean concentration of WSON during dust
events (38.2 ± 17.5 nmol N m−3) was 1.3 times higher than that
of non-dust events (29.4 ± 13.9 nmol N m−3). Source
apportionment analysis demonstrated that WSON was originated from
agricultural activities (43 %), secondary aerosol (20 %), nitrate
(22 %), crustal material (10 %) and sea salt (5 %). The dry and wet
depositions of WSON were equivalent and amounted to 36 % of the total
atmospheric WSTN flux.
Atmospheric Water Soluble Organic Nitrogen (WSON) over marine environments: a global perspective
