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A diagnostic study is made on the characteristics of regional difference of the Antarctic climatic change and the temporal and spatial multiplicity of the climatic change trend by using the temperature data for 1957 - 1993 from Antarctic and its vicinity, the data of sea ice northern boundary for 1973 - 1992 and the data of Antarctic total ozone for 1957 - 1992. The results show that there exists obvious regional difference for Antarctic climatic change, the climatic system is very complicated 9 and there were spatial and temporal multiplicity for temperature and ozone during the last 35 a and for Antarctic sea ice during the last 20 a. In recent years, the change of Antarctic temperature is not the same as global temperature. This kind of change and difference can not be easily explained by global greenhouse effect.
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The MSA and nssSO42- 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 vsnow/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 nssSO42- 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 SO42- 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 nssSO42- (or to SO42-) 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/nssSO42- ratio, both for atmosphere and snow, an important regional specificity for the study of marine biogenic sulphur.
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Stratigraphic variations of 18O/16O ratios of winter-accumulated snow at an alpine temperate glacier correspond to temporal patterns of local climatic variations. Although the snow is influenced by percolation and homogenization processes, the isotope stratigraphy in the glacier's accumulation area is not destroyed during the first part of summer. Below the equilibrium line altitude, rapid melting results in isotopic homogenization. Variation of δ18O values in the firn are relatively small.
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Weathering process of rocks in Antarctica can be accelerated by the colonization of lichens, which dominate surface vegetation and endolithic communities respectively in the maritime Antarctic and in Antarctic cold deserts. The effects of lichens on their substrate rocks can be attributed to both physical and chemical causes. As the result of the weathering induced by lichens, the surface corrosion and exfoliation of colonized rocks occur. The mobilization of iron in the rock-forming minerals and the precipitation of poorly ordered iron oxides are investigated. Furthermore, the neoformation of crystalline metal oxalates and secondary clay minerals are identified in the colonized rocks. Due to unique climatic conditions, the biotic weathering process of rocks in Antarctica somewhat differs from that of other regions of the world.
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An imaging riometer with 8×8 antenna array was installed successfully at Zhongshan Station, Antarctica in January 1997. The structure and working principle of the instrument are described. The first set of observation data is analyzed and the quiet day curve(QDC) are deduced. Preliminary results show that cosmic noise absorption is very different between night side and magnetic noon. In night side, there are often short-duration impulsive absorption events with a large absorption area in the northern side of the station, stretching in an east-west direction. In magnetic noon the absorption event is continuous, which lasts for more than 1 h with the absorption area strengthening in the northern and southern sides and weakening in the middle. It is thought that the absorption is caused by aurora particle precipitation in night side and by soft particle precipitation or convection in cusp at magnetic noon.
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The some trace elements in the Antarctic and Arctic snow, ice, water were studied using the methodology and theory of water vapor chemistry. The concentrations of ions Zn2+, Cd2+, Pb2+, Cu2+, Sn4+, Bi3+ in Antarctic and Arctic snow a significant spatial similarity; they are also close to those defined elsewhere on the basic of studies of water vapor chemistry: on average Zn2+ 5.0 μg/L, Cd2+ 0.080 μg/L, Pb2+ 0.030 μg/L, Cu2+ 0.70 μg/L, Sn4+ 0.99 μg/L, Bi3+ 0.18 μg/L. Apparently, the ion concentration in the Antarctic and Arctic region represent natural baseline values and are controlled by natural water cycles.
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The some trace elements in the Antarctic and Arctic snow, ice, water were studied using the methodology and theory of water vapor chemistry. The concentrations of ions Zn2+, Cd2+, Pb2+, Cu2+, Sn4+, Bi3+ in Antarctic and Arctic snow a significant spatial similarity; they are also close to those defined elsewhere on the basic of studies of water vapor chemistry: on average Zn2+ 5.0 μg/L, Cd2+ 0.080 μg/L, Pb2+ 0.030 μg/L, Cu2+ 0.70 μg/L, Sn4+ 0.99 μg/L, Bi3+ 0.18 μg/L. Apparently, the ion concentration in the Antarctic and Arctic region represent natural baseline values and are controlled by natural water cycles.
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The relationship of ECM with ice acidity and impurities concentrations are much different between the Qinghai-Tibetan Plateau and the polar regions. On the Qinghai-Tibetan Plateau, ECM is dependent on the mineral ions (i. e., Ca2+, Mg2+, SO42-, etc.) mainly derived from crustal sources, thus displays a positive linear correlation between ECM and these ions. While in polar ice sheets, however, ECM of snow and ice is mainly dependent on the acidic roots such as Cl-, SO42- and NO3- that mostly come from ocean. Therefore, there is good relationship between ECM and concentration of H+. However, the relationship between ECM and major ions has complicated geographical differentiation in the whole Arctic. For instance, there no longer exits the same simple relationship in the central Arctic as that in the Greenland Ice Sheet, probably due to the disturbance of Arctic haze. In general, ECM of snow and ice is a potential indicator of atmospheirc envirmment of cold regions.
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The relationship between polar sea ice anomalies and the precipitation and temperature anomalies over China is investigated by performing singular value decomposition (SVD) analyses. The first three coupling modes have been studied. Analyses show that there exist key areas of polar sea ice which are highly related with the precipitation and temperature anomalies over China. Different spatial anomaly patterns of these areas of polar sea ice are followed by different spatial anomaly patterns of the precipitation and temperature over China.
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Snow samples collected from two snow pits (2.5 m and 3.5 m deep) along the route of the 1996/1997 Chinese Antarctic Inland Expedition in Princess Elizabeth Land, East Antarctica, have been analyzed for chemical composition and oxygen isotope ratio. Annul accumulation layers can be well-identified based on fluctuations of major anions (especially Cl-) and δ18O. However, no obvious seasonal variations of cation concentrations were found in the profiles. The results provide a useful tool for dating the snow stratum in this region. High sulfate (SO42-) concentrations found in the two snow-pit profiles for the periods of 1992 - 1995 may be due to the June 1991 Pinatubo (Philippines) volcanic eruption and August 1991 Cerro Hudson eruption in Chile.
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In this paper, the characteristics of change in the Antarctic sea ice area are analysed by using the observed data from 1973 - 1986. The analysed results show that the monthly and annual change of the Antarctic sea ice area is obvious, the biggest change value is in 160°E - 120°W and 60°W - 100°E, the smallest value is in 110°E - 160°E and 120°W - 60°W. The relation between the Antarctic sea ice area and the Sea Surface Temperature (SST) in tropical Pacific is close, and the relation between the Antarctic sea ice area in each longitude belt and SST in tropical Pacific shows a clear difference. It is obvious that the Antarctic sea ice areas in 0° - 90°E and 100°E - 110°W have a different feedbacking relation with SST in the tropical Pacific. The notable relationship occurs in the 3-4 and 41-45 months, that quite tallies with the occurrence of El Nino.
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