The MSA and nssSO 2- 4 concentration data from the ice cores and from atmospheric aerosols of the regions surrounding Weddell Sea have been analyzed in the present paper. The results suggest that the high concen...The MSA and nssSO 2- 4 concentration data from the ice cores and from atmospheric aerosols of the regions surrounding Weddell Sea have been analyzed in the present paper. The results suggest that the high concentration of biogenic sulphur in the snow and ice as well as in the atmospheric aerosols reflects the proximity of the Weddell Sea even though a distinct strength discrepancy exists in the productivity among the areas. The snow/ice shows that the production seems to be higher in the middle of the Antarctic Peninsula than near the Filchner Ronne ice shelf. Despite the factors impacting on the transportation and deposition processes of biogenic surlphur, the concentration of MSA and nssSO 2- 4 in snow and ice shows a regular spatial distribution: decreasing with the distance from the open sea and the altitude above sea level. Nevertheless, below a certain height, the “altitude effect” is no longer significant. The “displacement” of seasonality for MSA concentration observed in ice cores of the regions has been discussed. The “out of phase” pattern in surface layer is attributed to the modification by prevailing meteorological condition to the transport and deposition process; while “relocation” in the deep layers may be caused by migration, a mechanism for which is to be further investigated.The comparative study of the atmospheric and snow/ice samples implies that at the high altitude like the Weddell Sea the atmospheric signal of SO 2- 4 and MSA could be somewhat muted in the snow samples. But the seasonal variations in the airborn sulphate and MSA are reasonably well reproduced in the surface snow, for temporal and spacial distribution. The very close ratio of MSA to nssSO 2- 4 (or to SO 2- 4) of atmospheric aerosol and snow/ice sample is indicative of weak, if any, fraction between the two species during the scavenging and deposition processes. This could serve as the internal cause to explain the relative stable MSA/nssSO 2- 4 ratio, both for atmosphere and snow, an important regional specificity for the study of marine biogenic sulphur.展开更多
Observations of atmospheric methane-sulfonic acid（MSA） and non-sea-salt sulfate（nss-SO4^2-） from December 2010 to November 2011 at Zhongshan Station are presented in this paper. MSA and nss-SO4^2- average concentr...Observations of atmospheric methane-sulfonic acid（MSA） and non-sea-salt sulfate（nss-SO4^2-） from December 2010 to November 2011 at Zhongshan Station are presented in this paper. MSA and nss-SO4^2- average concentrations were 24.2 ± 37.9 ng·m^-3（0.5-158.3 ng·m^-3） and 53.0 ± 82.6 ng·m^-3（not detected [n.d.]） - 395.4 ng·m^-3）, respectively. Strong seasonal variations of MSA and nss-SO4^2-, with maxima in austral summer and minima in winter, were examined. The high concentrations of sulfur compounds in December may be attributed the dimethyl sulfide（DMS） emissions from the marginal ice zone, when open water near the sampling site was important in impacting the sulfur species of January and February at Zhongshan Station. In austral winter, there was almost no phytoplanktonic activity in offshore waters, and atmospheric sulfur compounds likely had long-range transport sources.展开更多
文摘The MSA and nssSO 2- 4 concentration data from the ice cores and from atmospheric aerosols of the regions surrounding Weddell Sea have been analyzed in the present paper. The results suggest that the high concentration of biogenic sulphur in the snow and ice as well as in the atmospheric aerosols reflects the proximity of the Weddell Sea even though a distinct strength discrepancy exists in the productivity among the areas. The snow/ice shows that the production seems to be higher in the middle of the Antarctic Peninsula than near the Filchner Ronne ice shelf. Despite the factors impacting on the transportation and deposition processes of biogenic surlphur, the concentration of MSA and nssSO 2- 4 in snow and ice shows a regular spatial distribution: decreasing with the distance from the open sea and the altitude above sea level. Nevertheless, below a certain height, the “altitude effect” is no longer significant. The “displacement” of seasonality for MSA concentration observed in ice cores of the regions has been discussed. The “out of phase” pattern in surface layer is attributed to the modification by prevailing meteorological condition to the transport and deposition process; while “relocation” in the deep layers may be caused by migration, a mechanism for which is to be further investigated.The comparative study of the atmospheric and snow/ice samples implies that at the high altitude like the Weddell Sea the atmospheric signal of SO 2- 4 and MSA could be somewhat muted in the snow samples. But the seasonal variations in the airborn sulphate and MSA are reasonably well reproduced in the surface snow, for temporal and spacial distribution. The very close ratio of MSA to nssSO 2- 4 (or to SO 2- 4) of atmospheric aerosol and snow/ice sample is indicative of weak, if any, fraction between the two species during the scavenging and deposition processes. This could serve as the internal cause to explain the relative stable MSA/nssSO 2- 4 ratio, both for atmosphere and snow, an important regional specificity for the study of marine biogenic sulphur.
基金supported by the National Natural Science Foundation of China (NSFC) (Grant nos. 41476172, 41230529, 40671062, and 41106168)the Chinese Polar Environment Comprehensive Investigation & Assessment Programs (Grant no. CHINARE2012-15 for 01-04-02, 02-01, and 03-0402)International Cooperation Programs, Chinese Arctic and Antarctic Adminstration (Grant nos. 2G22010, IC201201, IC201308, and IC201513)
文摘Observations of atmospheric methane-sulfonic acid（MSA） and non-sea-salt sulfate（nss-SO4^2-） from December 2010 to November 2011 at Zhongshan Station are presented in this paper. MSA and nss-SO4^2- average concentrations were 24.2 ± 37.9 ng·m^-3（0.5-158.3 ng·m^-3） and 53.0 ± 82.6 ng·m^-3（not detected [n.d.]） - 395.4 ng·m^-3）, respectively. Strong seasonal variations of MSA and nss-SO4^2-, with maxima in austral summer and minima in winter, were examined. The high concentrations of sulfur compounds in December may be attributed the dimethyl sulfide（DMS） emissions from the marginal ice zone, when open water near the sampling site was important in impacting the sulfur species of January and February at Zhongshan Station. In austral winter, there was almost no phytoplanktonic activity in offshore waters, and atmospheric sulfur compounds likely had long-range transport sources.
