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    30 March 1962, Volume 23 Issue 1-English Previous Issue    Next Issue

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    PROGRESS AND PROSPECTS IN CHINESE ANTARCTIC SURVEYING, MAPPING AND REMOTE SENSING STUDIES
    E Dongchen&ZHANG Shengkai
    2012, 23 (1-English):  1-8.  DOI: 10.3724/SP.J.1085.2012.00001
    Abstract ( 2118 )   PDF (218KB) ( 1766 )  

    The Antarctic surveying, mapping and remote sensing is one of the important parts of Chinese Antarctic geoscience researches. Since the first Chinese National Antarctic Research Expedition (CHINARE) in 1984, the Chinese Antarctic surveying, mapping and remote sensing has been 25 years and made some progress. During 1980’s, the geodetic datum, height systems and absolute gravity datum were established in the Great Wall Station and Zhongshan Station. Great contributions were made for the constructions of the Chinese Great Wall Station, Zhongshan Station and Kunlun Station. The geodetic control network and gravity network were established in the King George Islands, Grove Mountains and Dome A. More than 200000 km2 areas were mapped using satellite image data, aerophotogrametry and in situ data. The permanent GPS stations and tide gauges were established in both Great Wall Station and Zhongshan Station. The plate motion, the precise satellite orbit determination, the gravity field, the sea level change and the GPS application in atmosphere studies were carried out. Based on the remote sensing techniques, the ice sheet and glacier movements, the distributions of blue ice and ice crevasse and mass balance studies were made. The polar digital and visual mapping techniques were introduced, the polar survey space database were built, the Chinese polar scientific expedition management information system and Chinese PANDA plan display platform were developed, which provide technique support for the Chinese polar management. Finally, the prospects of Chinese Antarctic surveying, mapping and remote sensing are put forward.

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    Articles
    The intensity ratio I (5577)/I (4278) at Zhongshan Station in Antarctica
    HU Guoyuan, AI Yong & ZHANG Hong
    2012, 23 (1-English):  9-11.  DOI: 10.3724/SP.J.1085.2012.00009
    Abstract ( 2030 )   PDF (186KB) ( 986 )  

    The auroral intensity ratios at Zhongshan station on April 8, 1999 were discussed, together with the variety of penetrated electron energy, it is concluded that the ratios of I(557.7nm)/I(427.8nm) during quiet period varied from 5 to 22, as well as I(630.0nm)/I(427.8 nm) from 1 to 2.76, and the cause for the change was not the atomic oxygen concentration variety, but the penetrated electron energy variety or other mechanisms; the ratios decreased sharply during the auroral substorm, varied from 1.66 to 6.5 and 0.071 to 1 respectively, which mainly caused by the increase of penetrated electron energy. At the beginning of the auroral substorm, the ratios reached its minimum; means that the penetrated electron energy got its maximum, while auroral substorm wear off, the penetrated electron energy come back to the level of pre-substorm.

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    The distribution and demography of Euphausia superba in Prydz Bay during the austral summer 2002
    LIU Yongqin, SUN Song, ZHANG Yongshan & LIU Huilian
    2012, 23 (1-English):  12-18.  DOI: 10.3724/SP.J.1085.2012.00012
    Abstract ( 1477 )   PDF (381KB) ( 786 )  

    This study documents horizontal distribution and demography of Antarctic krill (Euphausia superba Dana), which collected by IKMT along three transects from the Prydz Bay during January 2002. E. superba dominated south of 64°S, and few krill was found north of 64°S. The average density/biomass, estimated from trawl catches, was 68.85 ind/1000 m3 or 24.16 g/1000 m3. The four stations with highest values were located in the open sea. Body length ranged from 30 to 55 mm (N = 1758), with a mean of 38.45 ± 3.68 mm (SD). The overall sex ratio was 1:1, 47.6% females (31.9% sub-adults and 5.7% adults), 46.6% males (42.7% sub-adults and 3.9% adults), while 5.8% were juveniles. The population structure of E. superba showed geographical difference. The high proportion of juvenile, low sexual maturity stage of male and good growth condition was found in the western part of the survey area, and the reverse was presented in the eastern part. The latitudinal difference was found at stations along 70.5°E and 73°E: the body length was small and sex ratio was high in the region of high latitude, while the size was large and sex ratio was low in the region of low latitude.

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    The adaptation of Arctic phytoplankton to low light and salinity in Kongsfjorden(Spitsbergen)
    CUI Shikai, HE Jianfeng, HE Peimin, ZHANG Fang, LIN Ling & MA Yuxin
    2012, 23 (1-English):  19-24.  DOI: 10.3724/SP.J.1085.2012.00019
    Abstract ( 1812 )   PDF (243KB) ( 1332 )  

    Abstract The basic environmental variables and adaptability of phytoplankton communities to low light and salinity were studied with incubation experiments in Kongsfjorden, a high Arctic fjord of Spitsbergen, in late summer 2006. The results showed a significant halocline occurred in the water column. The depths of euphotic zone were between 25 m and 30 m with a decrease tendency from outer fjord to inner fjord. The chlorophyll peaks were observed in water column between 10 and 20 m depths. The experiment results illustrate that, the chlorophyll a concentrations maintain or decrease slightly in darkness after one-day or one-week incubation. The chlorophyll a concentrations showed an initial decline when exposed to nature light after one-week incubation in darkness, and then increase significantly. In the salinity experiment, the maximal growth rate was observed at a dilution ratio 10%, however, higher dilution ratios (≥40%) had a obvious negative effect on phytoplankton growth. The study reveals the phytoplankton in fjord in late summer have the ability of darkness adaption. It also suggests that the inflow of glacial melting water is helpful for phytoplankton growth in outer fjord where the dilution rates are low.

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    Grove Mountains (GRV) 024237: A New Ureilite from Antarctica
    JIANG Xiaoying, WANG Guiqin, WANG Daode & MIAO Bingkui
    2012, 23 (1-English):  25-29.  DOI: 10.3724/SP.J.1085.2012.00025
    Abstract ( 1823 )   PDF (241KB) ( 967 )  

    Ureilite, a special group of achondrites, has both the characteristics of differentiated meteorites and those of primary chondrites. GRV 024237 is an ureilite which was found in the 19th Chinese Antarctic Research Expedition (CHINARE), at the No.4 moraine, Grove Mountains, Antarctica. GRV 024237 mainly consists of coarse granular assemblages of olivine (60 vol%), pigeonite (30 vol%) and opaque mineral (10 vol%). Black grain boundaries are filled by carbonaceous material with a trace of troilite and nickel-iron metal, and 120°junctions are common. The Fa of olivine composition varies from 6.2 to 16.77 from its rim to core, but pyroxene is uniform in composition with Fs 14.0 to 15.5. The opaque phases are mainly graphite, troilite and Fe-Ni metal. GRV 024237 has normal extinction, net-like iron or limonite veins, no diamond and moderate FeO /MgO(Fo 84.8/Fa15.2)ratio. According to different model for sub-group classification, GRV 024237 is a typical monomict ureilite,and it belongs type I and group 2.

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    Temperature biases in modeled polar climate and adoptions of physical parameterization schemes
    LIU Xiying, ZHAO Jiahua, Xia Huasheng, BAI Tonggui & ZHANG Tao
    2012, 23 (1-English):  30-40.  DOI: 10.3724/SP.J.1085.2012.00030
    Abstract ( 1979 )   PDF (501KB) ( 1035 )  

    An annual cycle of atmospheric variations for 1989 in the Arctic had been simulated with WRF model with extension for polar climate. A severe cold bias was found around cold center in surface air temperature over the Arctic Ocean compared with results from ERA-Interim reanalysis. Four successive numerical experiments have been carried out to find out the reasons. The results show that, sea ice albedo scheme has the biggest influence in summer and the effect of cloud microphysics scheme is significant in both summer and winter. The effect of phase transition between ice and water has the biggest influence over the region near the sea ice edge in summer and gives little contribution to the improvement of the severe cold bias. The original rude consideration of albedo parameterization in surface process scheme is the main reason for the large simulated cold bias of cold center in summer. With another land surface scheme other than the one in control run, the cold biases of simulated surface air temperature over the Arctic Ocean is reduced greatly with a value up to 10 K at most, implying that land surface scheme is critical for polar climate simulation.

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    Content Analysis of documents using neural networks: A study of Antarctic Science Research articles published in international journals
    DASTIDAR,Prabir G & JHA,Deepak Kumar
    2012, 23 (1-English):  41-46.  DOI: 10.3724/SP.J.1085.2012.00041
    Abstract ( 2025 )   PDF (169KB) ( 1189 )  

    Content analysis of 25 years of research papers emanating from Antarctic science research was done. Neural network based algorithm-CATPAC was used for the analysis. 10942 research articles published in Science Citation Indexed (SCI) journals were used for this study. Normalized co-word matrix from 35 most-used significant words were used to study the semantic association between the words. Structural equivalence blocks were constructed from the 35 most-used words. Four-block model solution was found to be optimum. The density table of words was dichotomized using the mean density of the table to derive the binary matrix, which was used to construct the network map. Network maps represent thematic character of the blocks. The blocks showed preferred connection in establishing semantic relationship with other blocks, characterizing thematic composition of Antarctic science research. The analysis provided an analytical framework for carrying out dynamic analysis of the content of articles.

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    Trends
    Dome Argus: Ideal site for deep ice drilling
    TANG Xueyuan, SUN Bo, LI Yuansheng, LI Xin & CUI Xiangbin
    2012, 23 (1-English):  47-54.  DOI: 10.3724/SP.J.1085.2012.00047
    Abstract ( 1903 )   PDF (237KB) ( 1134 )  

    Dome A is the highest dome summit in the East Antarctic ice sheet and may represent a potential site for drilling deep ice cores containing old climate records. None of the existing sites with site selection are discussed. In this review, based on International Partnerships in Ice Core Sciences (IPICS), we present a perspective on recent developments in glaciological research at Dome A. This involves testing ideas behind drilling and their related goals, which have been involved in many glaciological branches. To select a suitable drilling site with a deep ice core, information pertaining to meteorology, glacial landforms, ice thicknesses, subglacial topography, ice velocity, internal structures, and others has been gathered. Focusing on the drilling issues, we systematically discuss the merits and motivations of potential drilling sites around Dome A. Among the sites of interest, we find that the location of the Kunlun station is superior for carrying out the first deep ice core drilling campaign. We also emphasize and assess the need to obtain a replicate core for investigating the dynamics and evolution of climate change.

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