Arctic Aerosols: Composition, Sources and Transport

摘要: Arctic aerosols originate from anthropogenic, marine and terrestrial soil sources as well gas to particle conversion of gaseous sulphur, nitrogen hydrocarbon compounds. The anthropogenic aerosol commonly known haze peaks in concentration (SO4 = 1.5 4 μg m−3) the northern lower troposphere (0 5 km) about November May. It is a minimum summer (~ 0.1 m−3). composition varies with size. Below 1 μm diameter, they are predominantly acidic sulphates black carbon inclusions half particles. Above μm, consist mainly sea salt derived particles that have been modified by reaction sulphur compounds organic gases form formate acetate. Wind blown dust transported southern desert spring months April May when storms most common source regions transport north still strong. Sea peak mostly period October result stormier conditions oceans during winter year longer residence times arctic air than summer. Anthropogenic primary constituents (i.e. those released directly into atmosphere no precursors atmosphere), such carbon, Pb V, high December March while not only component but also precursor SO4 tend over convert at polar sunrise. Halogens Br I origin different seasonal cycle above. Both sunrise has secondary September October. sulphuric acid implicated tropospheric ozone depletion ocean. region markedly altitude, phenomenon critical understanding deposited glaciers. glaciers range altitude 1.6 km on Ellesmere Island 3 Greenland 5.5 Mt. Logan Canadian Rockies. At altitudes winter, materials favours Eurasian sources. As increases potential expands include North American southeast Asian well. This qualitative picture consistent lead isotope observations Arctic.