Characteristics Of Soluble Ions In Aerosols On Glacier No.1at The Headwater Of Urumqi River, Tianshan Mountains, China

Global and regional climate change is a major issue for human beings. As animportant factor, aerosol impacts on climate undoubtedly, and it needs for furtherresearch. Study aerosol in glacier area, can not only understand the background ofambient air affected by human activities, but also rebuilt aerosol variation in historyaccording to the records which reserved in the snow and ice of glacier. Furthermore,the glacier area (Urumqi Glacier No.1) is adjacent to source area of central Asian dust,study aerosol in the area can provide basic data for dust transport mechanism. InUrumqi Glacier No.1, a typical glacier area of Tianshan Mountain,155aerosolsamples were collected in2003,2004,2007, and soluble ions (Ca2+, SO42-, NO3-,NH4+, Na+, Mg2+, K+, Cl-) in these samples were detected. Through analyzing theconcentrations of these ions, some important results were gotten and listed below:(1) The average concentration of soluble ions is2.759μg/m3. NO3-, SO42-, Ca2+and CO32-are major composition, account for about82%of the total water-solubleions.Ambient air condition of the glacier area is alkaline.(2) Seasonal change of total soluble ions with downward tendency: summer,autumn, spring, winter. Concentrations of Ca2+, SO42-, CO32-, NH4+, Na+, Mg2+, K+, Cl-in different seasons are all downward tendency: summer, spring, autumn, winter.However, NO3-presents the downward tendency: autumn, summer, spring, winter.(3) Inter annual variation of total soluble ions is:2007>2004>2003, butdifferent ion does not correspond to this tendency. The changes of these ions can beroughly divided into four groups: the first is NO3-, SO42-and NH4+, they all have thehighest annual average concentration in2007; The second is Ca2+, CO32-and Mg2+,annual average concentration reaches high in2004and2007,2003is the lowest; Thethird is Na+and Cl-, conform the annual average concentration tendency:2003>2007>2004; the fourth is K+, its average concentration is very low, and no obvious change.(4) Concentrations of soluble ions mainly depend on the strength of dust.Gas-to-particle transformation which affected by the temperature and humidity is alsoan important factor for seasonal changes of these ions. Anthropogenic aerosol which produced by human activities such as transportation, industry and grazing near theglacier area play a main role on ambient air environment. Furthermore, biomasscombustion, decomposition of dead animals around or in the glacier area can not beneglect.(5) The main sources of these ions in glacier area including: Natural source (dustand salt lake); Anthropogenic source (cement and quarrying industry); Mix source(fossil fuel combustion, biomass burning, rotting of organisms). According to the airmass trajectory clustering analysis, Urumqi Glacier No.1is mainly under control bythree airflows which come from southwest, west and northwest. The three airflowspass through Ili River Valley or Ala Mountain Pass and reach to the surface of glacierarea. About4000m (Above Sea Level, ASL), large amount of dusts are carried by theflow and it will strongly impact ambient air environment of the glacier area.