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The Chinese Zhongshan Station in Antarctica and the stations in SvaDwd (Auroral station at Longyearbyen and NP station at Ny-Uesund) are closely magnetic conjugate. All of them are equipped similar measurement instruments dealing with upper atmospheric physics. Therefore, there is a good reason to conduct a cooperative research program between China and Norway to do the inter hemispheric comparisons of geospace environment in the polar regions. It will make significant contribution to further understanding of the coupled magnetosphere-ionsphere system. The scientific aims of the cooperative project are: to experimentally verify the modeled complicated conjugate relationship between Zhongshan Station in the Antarctic and Svalbard in the Arctic. To derive knowledge from the conjugate characteristics of auroral formations, ionospheric features and space plasma waves in the polar regions, which in turn will lead to better understanding of the solar wind-magnetosphere-ionosphere coupling processes. The proposed research contents, research methods and experimental techniques are discussed, and the manners of the cooperative research are suggested in the paper.
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Using the ground observation data at Zhongshan Station of Antarctica during July 13 to 17, 2000, the intense absorption events associated with the activities of the solar active region R9077 are analyzed. It was shown that an intense polar cap absorption event lasted more than 3 days, which was caused by the solar proton event associated with the X5/ 3B major flare at 1024 UT on July 13. The polar cap event started at about 1040 UT on July 14, and lasted to about 1940 UT on July 17, with a typical day night vaiiation At the same time, the intense solar activities extremely disturbed the magnetosphere, therefore aurora substorms occurred frequently. The energetic particle precipitation from the magnetosphere caused several absorption spikes superposing on the background of polar cap absorption. One distinct event is the absorption enhancement that started at about 0300 UT on July 15, reached its peak of 26 dB at about 0645 UT and rer covered at about 1110 UT on the same day, which was the strongest absorption event observed at Zhongshan Station since the imaging riometer installed in February, 1997. Another outstanding alsorption spike with pulsation occurred at about 1753 UT on 14th, its peak reached to 6 dB.
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In this paper we use the high-speed multrchannel meridian scanning photometer data and alhsky TV camera images to analyze the intensity variations of the postnoon auroral bright sports of 557. 7 nm and 630. 0 nm emissions. Several results can be obtained from this paper. (1) Bright spots are rather transient features lasting typically for only a few minutes. (2) The intensity of the postnoon bright spots of 557. 7 nm emissions can surpass 11 kR. The occurrence of the bright spots seems rather frequent. (3) The ratios of I(427. 8) /1(630. 0) and I(427. 8) /1(557. 7) during the bright spots occurring time show a positive peak and negative peak respectively. It qualitatively indicates that the average precipitating electron energies along the meridianal scan alcove Zhongshan Station increased as the bright spot appeared. And the intensification of the spot mainly was caused by the increasing of high energy (3-10 keV) flux. (4) Usually the bright spots are accompanied with the magnetic pulsation and the occurrence of multrband arcs.
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The fabrics and crystals of Bohai one-year ice show that the noncontinuous ice growth rate enables the level ice layers with different amount of air bubbles to be formed in lower part of an ice sheet which was clearly seen from CT technology; typical grain ice and columnar ice occur in the grey ice which grows in staJjle water; thaw refrozen ice and rafted ice have their specific crystal characters. On the Arctic sea ice, the ice core located at 72°24. 03/ N, 153°33. 994' Wand 2.2 m in length was a 3-year ice floe and a new sort of crystal was found, which is defined as refrozen clastic pieces. The crystal profile of the ice core 4.86 m in length located at 74°58. 614' N, 160°31. 830'W shows the evidence that ice ridge changed into hummock.
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Two induction magnetometers have been installed at Chinese Zhongshan Station and Australia Davis Station, Antarctica respectively. We adopt the cross-spectral analysis technique to analyze the data of the two induction magnetometers, in June, September, December 1996 and March 1997, and to investigate Pc5 frequency range pulsation (150-600 s) occurrence and propagation in cusp latitude. The results are summarized as follows: At ZhongsharrDavis Station, the magnetic pulsations in Pc5 frequency band can ocr curs over a wide time, hut more frequently at pre local magnetic noon and pre local magnetic midnight. The Pc5 pulsations have no significant seasonal variation in the amplitude, occurrence and propagation. The amplitude has a small peak at pre local magnetic noon and large value sometimes at pre local magnetic midnight. In daytime, the Pc5 pulsations propagate westward in morning and eastward in afternoon, and reversal at local magnetic noon. In nighttime, the Pc5 pulsations propagate westward before 20: 00 MLT and eastward after 20: 00 MLT. Near dusk time, the Pc5 pulsations propagate irregularly. These characteristics indicate that the Pc5 pulsations have different source at different local magnetic time.
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In this paper, the 18O distribution of surface water from the central sea areas of the Bering Sea and the Chukchi Sea was studied. The δ18O value of surface water from the Bering Sea is averagely - 0.5 ‰; the δ18O contents of the Chukchi Sea are distributionally lower in northeast and higher in southwest; the δ18O value at the margin of Canadian Basin is - 2.8 ‰, and averagely - 0.8 ‰ in the southern area of the Chukchi Sea. The δ18O vertical distribution in some deep water stations from the Chukchi Sea and the Bering Sea is also studied. In the southern margin of Canadian Basin, the δ18O value is - 2 ‰-3 ‰for surface layer and rises to 0 at 100 m depth layer. In the Bering Sea, the δ18O is about - 0.5 ‰ for surface layer and increases to 0 at the depth of 300 m. The NO tracer can reflect obviously three water masses vertically distributed in the central Bering Sea: the upper Bering water mass, the middle Bering water mass and the deep Pacific water mass. The distributive ranges of NO and temperature for the various water masses are T＜ 7 ℃, NO＞ 780 μmol/dm3 and T ≥7 ℃, NO＞ 650 μmol/dm3 for upper Bering water mass, T ＜ 4 ℃, 550＜ NO＜ 780 μmol/dm3 for middle Bering water mass, and T＜ 4 ℃, 330＜ NO＜ 550 Mmol/ elm for deep Pacific water mass. It is found from δ18O- S relation diagram and δ18O vertical profiles that the δ18O is al＞out + 0.3 ‰ from halocline layer till sea bottom. Its isotopic characteristics are the same as the Atlantic water, showing that the sea water comes from the north Atlantic. The freshwater enchmember of the Chukchi Sea in the survey period is ako explored.
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The Nippon/Norway Svalbard Meteor Radar(NSMR), has been in operation since March 2001. While primarily thought of as an instrument for examining mean wind, tidal and gravity wave neutral atmosphere dynamics in the upper mesosphere region, it is also possible to investigate spatial and temporal structure of temperature and windshear. Here, the radar itself is described followed by a presentation of these derived parameters.
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In this article we want to present the EISCAT SvaUwd Radar (ESR) in some detail, as well as some of the instruments of interest for ionospheric and magnetospheric research that are located in the vicinity of it. We particularly describe how this instrument cluster, close to the geomagnetic conjugate point of the Chinese Antarctic Zhongshan Statioru can contribute to inte「hemispheric coordinated studies of the polar ionosphere.
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This paper describes the Auroral Station in Adventdalen near Longyearbyen, Svalbard (78°N, 15°E). The main instruments at the site are for optical observation of aurora and airglow, hut magnetic and radar observations are also carried out. Emission spectra show the difference between the dayside and nightside optical aurora. A newly compiled mesospheric temperature series from the station is also presented, derived through 20 years of spectral measurements of the hydroxyl airglow layer.
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In 1999 summer, Chinese Arctic Research Expedition operated the Chukchi Sea. On Chinese icebreaker Xuelong, we made many highrresolution ozonesonds measurements. During the period from August 18 to 24, a synoptic scale observation was taken at 75°N, 160°W. Using the above data, together with TOMS total ozone and NCEP circulation data, we showed that atmospheric ozone amount experienced a high-low-high variation, with low-high-low tropopause altitude. Correlation analysis showed a close relation between the total ozone and ozone below 13 km, while the variation of the maximum concentration at aljout 20 km didn' t show any relation to the column ozone. In 500 hPa height maps, there was also the weak-strong-weak southwesterly pattern. Therefore we suggested that the synoptic system might he responsible to a low ozone advection during this ozone variation.
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Using the boundary layer observation data collected by "Arctie Upper Air Olr servation 1999" in Chinese Arctic Research Expedition 1999, a strong temperature inversion in summer is studied. It shows that the intensity (6.3 ℃/ (100 m)) is much stronger than the climatology average value in summer and winter. The temperature inversion took on a remarkable diurnal variation. The intensity of inversion gradually weakened from night to daytime.
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