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30 December 2010, Volume 22 Issue 4 Previous Issue    Next Issue
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CLIMATE CHARACTERISTICS OF PRECIPITATION AND WIND AS WELL PRESSURE AND CLOUD AMOUNT AT THE ANTARCTIC GREATWALL STATION (1985-2008) AND ZHONGSHAN STATION (1989-2008) 2010, 22 (4):  321-333.  DOI: 10.3724/SP.J.1084.2010.00321 Abstract ( 2220 )   PDF (761KB) ( 1571 )   The variations and trends of monthly, seasonal and annual mean precipitation and wind as well pressure and cloud amount are presented by surface meteorological observation data from the Greatwall station(GW) and Zhongshan station(ZS) at the Antractic. The annual mean precipitation is 503mm and its interannual variation trend is negative(-27mm/10a) at GW. The variation rates of annual precipitation days at GW and ZS are -2.9d/10a and -12.1d/10a separately. The annual mean of humidity at GW and ZS is 88% and 58% separately. Its interannual variation trend is less different and less significant at the both station. The prevailing wind is northwest direction at GW and eastern direction at ZS. The annual mean of wind speed is 7.3 m/s and 7.1 m/s as well their variation trend is -0.09m/s/10a and -0.23m/s/10a separately for GW and ZS. The annual mean days of strong wind is 137d and recorded maximum wind speed is 37.2 m/s at GW, and 159d and recorded maximum wind speed is 50.3 m/s at ZS. The annual mean of pressure is 88% and 58%, and the variation rate is 0.65 hPa/10a and -0.80hPa/10a separately at GW and ZS. The trends is opposite and similar the pattern with wind and strong wind days and precipitation days at both station. The annual mean of cloud amount is 8.8和6.2 separately at GW and ZS. Its difference shows that both station located in the different climate zone. Related Articles | Metrics

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OBSERVATION OF THE POLAR IONOSPHERIC HEATING EXPERIMENT IN SUMMER 2009 2010, 22 (4):  334-347.  DOI: 10.3724/SP.J.1084.2010.00334 Abstract ( 2215 )   PDF (4657KB) ( 1314 )   Using the incoherent scatter radar, the polar ionospheric modification experiments are carried out in summer 2009 at Troms, Norway. The electron temperature enhancements in the heating campaign can be distinguished to two kinds: a small scale structure near 150km with a larger relative enhancement and a large scale structure between 150km-400km with a stronger absolute value. The percent of the temperature enhancement linearly increases with heating power in all the heating case, and the increase velocity decreases with the pump frequency increase. A clear 2D distribution can be found in measurement on August 15, and the preponderant direction of heating effects is close to field-aligned. The heating effects are obviously affected by the angle between heating beams and field-aligned. With the increase of the angle, the increment of temperature decay. Related Articles | Metrics

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A REVIEW OF RESEARCH ON LATE NEOPROTEROZOIC EARLY PALEOZOIC（PAN-AFRICAN）GRANITOIDS FROM EAST ANTARCTICA 2010, 22 (4):  348-374.  DOI: 10.3724/SP.J.1084.2010.00348 Abstract ( 2384 )   PDF (3757KB) ( 1429 )   There exist two Pan-African orogenic belts, i.e. Maud and Prydz belts, in East Antarctica. Numerous syn- to post-tectonic granitoids occur in these two orogenic belts. In this paper we summarized the published petrological, geochemical and geochronological data of Pan-African intrusive rocks from the different areas in East Antarctica. A comparative study on rock types, magma sources and tectonic settings were performed. The results show that most granitoids have an affinity of A- or S-type granites related to collisional orogeny, except for granitoids from the S?r Rondane Mountains being I-type granites. The Pan-African granitoid magmatism occurred between 600 and 500 Ma, largely coeval with regional high-grade metamorphism. Granitoid magmatism in two orogenic belts is probably related to post-collisional lithospheric thinning, magmatic underplating and crustal relaxation, which is expected in a typical collisional tectonic setting. Therefore, The Gondwana supercontinent was probably formed by the final juxtaposition between West Gondwana, Indian-Antarctic and Australian-Antarctic continental blocks along the two sutures (Maud and Prydz belts) during the Pan-African time. References | Related Articles | Metrics

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Petrology and mineralogy of the Grove Mountains(GRV)024237 ureilite from Antarctica 2010, 22 (4):  375-385.  DOI: 10.3724/SP.J.1084.2010.00375 Abstract ( 2231 )   PDF (6054KB) ( 1358 )   GRV024237 was found at the No.4 moraine, Grove Mountains, Antarctica in the 19th Chinese Antarctic Research Expedition(CHINARE). GRV024237 consists of granular assemblage of olivine(60vol%), pigeonite(30vol%), the grain boundaries are black and filled by opaque minerals(10 vol%). 120°junctions are common. The chemical compositions of olivine are obviously zonal distribution. The values of olivine Fa are varied between 6.2 and 16.77 from the grain’s rim to core. However, the Fs of pigeonite are quite homogenous, which are between 14.0 and 15.5. The opaque minerals are black carbonaceous material, troilite and Fe-Ni metal. Based on our study, GRV024237 is a monomict ureilite, which is suffered light shock metamorphism and experienced partial melting. References | Related Articles | Metrics

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Variations of phosphatase activity in the soils impacted by seabird guano and its affecting factors 2010, 22 (4):  386-396.  DOI: 10.3724/SP.J.1084.2010.00386 Abstract ( 1867 )   PDF (646KB) ( 1427 )   Phosphatase plays an important role in microbial liberation of phosphorus in the soil systems. In this paper, the tundra ornithogenic soils were used to study the variations of the alkaline phosphatase activity (APA) with depths. Simultaneously, the organic carbon, total nitrogen, phosphorus, pH in the soils were also analyzed in these soils. The correlation between APA and soil chemical properties was discussed. In almost all soil profiles, the variations of APA showed the same patterns, the maximum appeared in the surface soils, and APA decreased with the soil depth. The APA ranged from 1.00 ppm to 1403.49 ppm with the average of about 408.31 ppm. APA showed a significant positive correlation with soil organic carbon (r=0.70, p<0.01) and nitrogen content (r=0.43, p<0.01), indicating that soil carbon and nitrogen contents were predominant factors affecting APA in polar soils. In addition, APA also positively correlated with inorganic phosphorus (r=0.40, p<0.05), organic phosphorus and total phosphorus（r=0.39, p<0.05）, suggesting that various forms of phosphorus, to some extent, affect APA in the soil systems. APA showed a significant negative correlation with Cu and Zn contents in the soils, indicating that Cu and Zn might inhibit APA in the polar soils. Our results showed that APA can be used as an important indicator of soil fertility in polar regions. Related Articles | Metrics

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DOM GENERATION AND PRECISION ANALYSIS OF FILDES PENINSULA BASED ON QUICKBIRD IMAGES 2010, 22 (4):  397-403.  DOI: 10.3724/SP.J.1084.2010.00397 Abstract ( 1826 )   PDF (1331KB) ( 1394 )   Fildes Peninsula is one of the most significant regions for polar scientific research. The high resolution digital orthoimage map(DOM) of this region provides important information. However, influenced by the quality of ground control points(GCPs) and DEM , the existed DOMs are inadequately precised for high accuracy application. Regarding this, this paper addresses DOM generation based on QuickBird images of Fildes Peninsula. Combined with the GCPs collected during CHINARE-25 and the DEM created from the 1:20000 topographic map, the ortho rectification model and height displacement are meliorated. The result shows that the plane error of the image is less than 1 meter, which can meet the requirements of 1:5000 remote sensing cartographic map. References | Related Articles | Metrics

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A study of water properties and convection under sea ice in winter Amundsen Gulf 2010, 22 (4):  404-414.  DOI: 10.3724/SP.J.1084.2010.00404 Abstract ( 1715 )   PDF (1920KB) ( 1580 )   The convection under sea ice in winter Amundsen Gulf without solar heating is studied. The data we used are from Circumpolar Flaw Leads System Study project (CFL) during the time of polar night from November 2007 to the end of January 2008. It is shown that the vertical haline convection is the main character of the sea water in winter time in this region. The thickness of the mixed layer varies from meters to tens of meters. No static instability is found, i.e. the density of the water in mixed lyaer is lower than that of the water below. Unlike the convection others studied, the convection we observed is caused by continual released haline parcel. The temperature of the water in the mixed layer is almost at the freezing point, which is the result of the haline/density convection during the period of the ice formation. Below the mixed layer, there is a warm layer. But the temperature decreased with time during the observation period. We think, the main reason for it is the energy exchange with the water in mixed layer. According to the results, the salinity and thickness of the mixed layer coincide in early winter, while the thickness decreased in late winter with the salinity increasing. We also analyzed the temperature and salinity data from 3 stations which are coarsely at the same position and found that the salinity of the mixed layer increased and the temperature of the warm layer decreased during the observation period. Related Articles | Metrics

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ARCTIC ENVIRONMENTAL CHANGE ON CHINA′S NON TRADITIONAL SECURITY 2010, 22 (4):  415-422.  DOI: 10.3724/SP.J.1084.2010.00415 Abstract ( 2212 )   PDF (354KB) ( 2582 )   With the warming of global environmental issues, Arctic environmental change is paid more and more attention by the international community. China,which is a near-Arctic country, is greatly influenced by the change. The paper will analyse the impact which the Arctic environmental change may influence on China from environmental security, economic security, resource security, and other non-traditional security factors. From environmental security, the Arctic environmental change will have a direct threat to the future on the ecological environment. The Arctic sea ice could be melt by rising temperatures which will lead to a huge social and economic harm in China; From the economic safety, Arctic environmental change will bring the full opening of the Arctic channel, which may be an opportunity for China's development in the future, but if China wants to shipping in the Arctic resource development on a slice will have multiple obstacles; From resource security, the rich Arctic is significant to China. However, given the current problems in China's participation in the Arctic, even if the resources can be a well developed, it is mainly vested in the Arctic countries. China energy supply will be controlled by others, which can not fundamentally protect the safety of China's energy strategy. Related Articles | Metrics

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Monitoring and distribution system about TEC of polar ionosphere Song-Tao AI Ze-Min WANG 2010, 22 (4):  423-430.  DOI: 10.3724/SP.J.1084.2010.00423 Abstract ( 2451 )   PDF (730KB) ( 2506 )   Polar regions are ideal places to investigate physical phenomenon of higher atmosphere and solar-terrestrial relationship, and GPS-based TEC extraction has advantages of high precision, all weather and large field, so it is significant to research polar ionosphere using GPS. Monitoring and distribution system about TEC, designed in this paper, contains data transmission, data processing, data distribution. Data transmission contains satellites network and formats conversion. Data processing means by using the GPS dual-frequency data, VTEC of single station is calculated, with DCB solved first and twice modeling second. The result shows that this method reflects value and variation of TEC exactly. Data distribution means real-time online inquiry service, supported by Chinese Polar Scientific Expedition Management Information System. Related Articles | Metrics

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REVIEW OF THE CURRENT STATUS AND FUTURE DEVELOPMENT OF ANTARCTIC SPECIALLY MANAGED AREA 2010, 22 (4):  431-440.  DOI: 10.3724/SP.J.1084.2010.00431 Abstract ( 1931 )   PDF (2269KB) ( 1607 )   Antarctic specially managed areas (ASMAs) play an important role of the system of Antarctic environment protection, which covers over 50,000 square kilometers. According to the text released by the Antarctic Treaty Secretariat (ATS), we briefly introduce the current status , preparation of management plans and proposed procedures of the ASMAs.Up to Antarctic Treaty Consultative Meeting XXXII, there are seven ASMAs designated and sixteen proponents , mainly include Australia and USA. China is one of the proponents of Antarctic specially managed area in Larsemann Hills, East Antarctica. In addition, The paper proposes the problems with solutions and analysis the development of ASMAs. Related Articles | Metrics