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In the paper, by use of the monthly mean temperature data of 12 stations in the vicinity of Antarctic Peninsula, the temperature series during 1903-2000 is founded and the interdecadal oscillation of the temperature are discussed. The results indicate that 1) There are three jumps during 1919-1923, 1947-1953 and 1976-1982 in recent hundred years and the stable climate step between two jump points lasted about 30 years. 2) Annual mean temperature is increased by 0.730℃ in an echelon during 1903 - 2000, the warming extent is dissimilarity in each season, the maximum of warming is in the winter and the minimum of warming is in summer. 3) The ice decline trend is presented in the index of Ice concentration in the vicinity sea of Antarctic Peninsula, which shows a - 0.2053/10a drop, and the decrease trend of the ice concentration index in summer half year (Dec-May) is found much more obviously than that in winter half year (Jun - Nov). 4) There is better negative relationship between the temperature and the Ice concentration index in Antarctic Peninsula and its vicinity sea, which correlation coefficient of is exceed the significance level of 5% in summer, autumn and annual.
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Abundance, biomass and composition of the ice algal and phytoplankton communities were investigated in the southeastern Laptev Sea in spring 1999. Diatoms dominated the algal communities and pennate diatoms dominated the diatom population. 12 dominant algal species occurred within sea ice and underlying water column, including
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107 strains producing protease were screened from 260 strains of Antarctic psychrophilic bacteria, among which proteolytic activity of five strains was more than 45 U ml-1. The 16S rRNA gene sequences homology and phylogenetic analysis of five Antarctic psychrophilic bacteria showed that NJ276, NJ5-9, NJ16-70, NJ345 belonged to the described genus
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The reconstruction of air trapped in ice cores provides us the most direct information about atmospheric CH4 variations in the past history. Ice core records from the "Three Poles (Antarctica, Greenland and Tibetan Plateau)" reveal the detailed fluctuations of atmospheric CH4 concentration with time and are allowed to quantify the CH4 differences among latitudes. These data are indispensably in the farther study of the relationship between greenhouse gases and climatic change, and of the past changes in terrestrial CH4 emissions. Ice cores reconstruction indicates that atmospheric CH4 concentration has increased quickly since industrialization, and the present day’s level of atmospheric CH4 (1800 pp-bv) is unprecedented during the past Glacial-Interglacial climate cycles.
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The concentrations of organic carbon(OC) and elemental carbon(EC)in total suspended particle (TSP) were investigated at Ny-Ålesund, Svalbard in a two-week campaign. The levels of OC and EC are 0.86 ± 0.27 pgm-3 (mean ± standard deviation) and 0.19 ± 0.10 /igm-3, respectively. Back trajectory analysis of air masses arriving at Ny-Ålesund reveals that long-range transport of polluted air play insignificant role in OC and EC levels, to which the potential influence of the local contamination were ascribed. The average OC/EC ratio is 5.41, suggesting the presence of the secondary organic aerosols. The estimated second' ary organic carbon (SOC) in TSP is 0.59 μg/m3. accounting for 64% Vo of the total organic carbon.
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Based on the Germany Koldwey Station's 1994-2003 conventional ob-servation hourly data, this paper conducts a statistical analysis on the short-term climate characteristics for an arctic tundra region (Ny-Ålesund island) where our first arctic expedition station (Huanghe Station) was located. Affected by the North Atlantic warming current, this area has a humid temperate climate, and the air temperature at Ny-Ålesund rose above 0℃ even during deep winter sea-son during our research period. The wind speed in this area was low and appeared most at southeast direction. We find that the temperature at Ny-Ålesund rose in the faster rate (0.68℃/10 a) than those at the whole Arctic area. Compared with the floating ices where our expedition conducted in the Arctic, Ny-Ålesund was warmer and more humid and had lower wind speed. Comparison of the near surface air temperature derived by NCEP/NCAR reanalysis to the conventional measurements conducted at the Koldwey site in Ny-Ålesund area shows a good a-greement for winter season and a significant difference for summer season.
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The elemental and isotopic signatures in the sediments influenced by seal excrement on Antarctic Fildes Peninsula are examined for their potential palaeoecological applications. The seal hair abundance in sediments exhibits re-markable fluctuation versus depth, indicating similar changes in historical popula-tions of the seals visiting the marine terrace. The combination of δ13C, total or-ganic carbon concentration (TOC), total nitrogen concentration (TN) and atomic C/N ratio shows that the organic matters in sediments with numerous seal hairs have a marine origin and are predominantly derived from seal excrements. The large δ15N values in sediments are attributed to trophic enrichment and NH3 vol-atilization processes. The large variations in the δ15N values and the negative cor-relation between the δ15N values and the seal hair abundances seem to be the re-sults of changes in the paleoclimates and the volatilization rates of the ammonia produced in the seal excrements. The 87Sr/86 Sr ratios in the acid-soluble fraction of sediments are interpreted as a mixture of the ones from the seal excrements (30% - 50%) and the chemically weathered local bedrocks (70% - 50%). The cal-culated proportion of seal-derived Sr based on the 87Sr/86 Sr ratios has a signifi-cant correlation with seal hair abundances in sediments. These results suggest that δ15N values and the 87Sr/86 Sr ratios in the acid-soluble fraction of sediments were influenced by seal excrements, similar to seal hair numbers, and thus can potentially be used to estimate the historical seal population in the Antarctic re-gion.
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