Long-term variability of inorganic ions in TSP at a remote background site in Japan (Wajima) from 2005 to 2015

Eleven years (2005–2015) of data from long-term monitoring at a Japanese remote background site in Wajima, were analyzed to investigate temporal trends and sources. Water-soluble inorganic ions (WSIIs) for aerosol chemical composition. The total WSIIs concentration was 7.93 ± 3.93 μg/m3, accounting 42.3% TSP mass, ranged 11.4 93.9%. SO42− is the most abundant ion, contributing WSII mass 18.0 79.8%, non-sea-salt (nss-) contributed 63.6% 99.6% SO42−, which related human activities on Asian continent effects marine precursors spring summer, respectively. NO3− NH4+ contribute 6.3 7.4% affected by long-range transport local sources as well. increasing trend Na+ Cl− indicates increased influence sea salt, caused more frequent strong winds. K+ mainly produced biomass burning with stable seasonal variation, Ca2+ characteristic ion dust has highest spring. Mg2+ comes minerals during This work describes detail annual change atmospheric particles Wajima area, characteristics, source contributions, provide comprehensive understanding variation particulate.