The seasonal characterization of dust days, mass concentration and dry deposition of atmospheric aero-sols were investigated using the historical data of dust days observed over Qingdao during the period from 1961 to ...The seasonal characterization of dust days, mass concentration and dry deposition of atmospheric aero-sols were investigated using the historical data of dust days observed over Qingdao during the period from 1961 to 2001 and ground-based aerosol sampling data collected in the period from May 2001 to November 2002. In Qingdao most of the dust days occurred in spring and in winter and no dust days existed in summer. The seasonal variation of the uplifting dust day over Qingdao was in phase with that analyzed over North China. The mean mass concentration of the total suspended particles (TSP) in spring, summer, autumn and winter was respectively 300, 110, 113 and 185 mg.m-3. The values and phase of the seasonal oscillation for fine particles were very similar to those for coarse particles except for the month March, during which the concentration of the coarse particles was about 4 times as high as that of the fine parti-cles. Comparison between seasonal variation of mass concentration of aerosols and dust days indicated that high frequency of uplifting dust day was accompanied by high TSP mass concentration. The TSP mass concentration meas-ured by the low-volume instrument was about 30% lower than that measured by high-volume instrument, though the two data sets are highly correlated (correlation coefficient=0.89). The dry deposition flux during the observation period from May 2001 to November 2002 ranged from 0.06 to 0.2 g.m-2.d-1 with a mean value of 0.13 g.m-2.d-1, which was about 1/3 as that over Beijing.展开更多
文摘The seasonal characterization of dust days, mass concentration and dry deposition of atmospheric aero-sols were investigated using the historical data of dust days observed over Qingdao during the period from 1961 to 2001 and ground-based aerosol sampling data collected in the period from May 2001 to November 2002. In Qingdao most of the dust days occurred in spring and in winter and no dust days existed in summer. The seasonal variation of the uplifting dust day over Qingdao was in phase with that analyzed over North China. The mean mass concentration of the total suspended particles (TSP) in spring, summer, autumn and winter was respectively 300, 110, 113 and 185 mg.m-3. The values and phase of the seasonal oscillation for fine particles were very similar to those for coarse particles except for the month March, during which the concentration of the coarse particles was about 4 times as high as that of the fine parti-cles. Comparison between seasonal variation of mass concentration of aerosols and dust days indicated that high frequency of uplifting dust day was accompanied by high TSP mass concentration. The TSP mass concentration meas-ured by the low-volume instrument was about 30% lower than that measured by high-volume instrument, though the two data sets are highly correlated (correlation coefficient=0.89). The dry deposition flux during the observation period from May 2001 to November 2002 ranged from 0.06 to 0.2 g.m-2.d-1 with a mean value of 0.13 g.m-2.d-1, which was about 1/3 as that over Beijing.
