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11.
1 IntroductionAlongwiththearrivalof2 3rdsolaractivepeakandthedevelopmentofthespacesci ence ,thescientistsaremoreandmoreinterestedintopicsofgeospaceeffectscausedbytheintensesolaractivities.Thegeospaceeffectsofseveralextremesolaractiveevents,suchasthe 1 993No…  相似文献   
12.
A new auroral imaging system is reported which is planned to be deployed at Zhongshan Station in Antarctica in the end of 2009. The system will focus on study of optical auroras in small scales and be called China' s Auroral Fine-structure Imaging System (CAFIS). The project of CAFIS is carried out by support of 'the tenth five-year plan for capacity building' of China. CAFIS will be a powerful groundbased platform for aurora observational experiments. Composing and advantages of CAFIS are introduced in this brief report. Some potential study topics involved CAFIS are also considered.  相似文献   
13.
南极的日地物理观测研究   总被引:3,自引:0,他引:3  
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14.
南极中山站的f_0F2特征   总被引:3,自引:0,他引:3       下载免费PDF全文
本文利用电离层数字测高仪 (DPS - 4)所测的f0 F2和从美国NOAA和DMSP卫星观测估算的半球功率指数和午夜极光区赤道侧边界纬度等资料 ,考察中山站电离层的极区特征。结果表明 ,冬季中山站电离层内的电离生成主要取决于从磁层沉降的粒子。在太阳活动和地磁变化宁静环境下 ,磁正午极隙区内的软粒子是最主要的电离源 ,它能使f0 F2达全天的最大值 ;上、下午各有数小时处于极光带内时 ,高能粒子的电离作用也很重要 ;夜间进入极盖区后 ,电子密度则很低。夏季太阳辐射电离效应使f0 F2值比冬季增加 1- 1 .5MHz,而其日变化的最大值时间也提前了 1- 2hr。发生很大扰动时 ,极隙区和极光带的位置均向低纬方向移动。若中山站日间也处于极盖区内时 ,电子密度会大幅度下降 ,并常接收不到电离层回波的信号。在中等扰动环境下情况更加复杂。由于高纬电离层对流速度很高 ,离子 /中性分子间的碰撞复合系数就很大。热层中性大气全球经向环流对高纬电离层电子密度的增加无显著作用。磁暴期间中午从极隙区向南的等离子体对流对中山站f0 F2的增高也无明显影响。  相似文献   
15.
MeanionosphericpropertiesinwinteratZongshanStation,AntarcticaTX@刘顺林@贺龙松@刘瑞源MeanionosphericpropertiesinwinteratZhongshanStation,An...  相似文献   
16.
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 variation. 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 recovered 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 absorption spike with pulsation occurred at about 1753 UT on 14th, its peak reached to 6 dB.  相似文献   
17.
A new auroral imaging system is reported which is planned to be deployed at Zhongshan Station in Antarctica in the end of 2009.The system will focus on study of optical auroras in small scales and be called China' s Auroral Fine-structure Imaging System(CAFIS).The project of CAFIS is carried out by support of 'the tenth five-year plan for capacity building' of China.CAFIS will be a powerful ground-based platform for aurora observational experiments.Composing and advantages of CAFIS are introduced in this brief report.Some potential study topics involved CAFIS are also considered.  相似文献   
18.
A new auroral imaging system is reported which is planned to be deployed at Zhongshan Station in Antarctica in the end of 2009.The system will focus on study of optical auroras in small scales and be called China' s Auroral Fine-structure Imaging System(CAFIS).The project of CAFIS is carried out by support of 'the tenth five-year plan for capacity building' of China.CAFIS will be a powerful ground-based platform for aurora observational experiments.Composing and advantages of CAFIS are introduced in this...  相似文献   
19.
南极中山站冬季电离层的平均特性   总被引:7,自引:3,他引:7       下载免费PDF全文
本文利用南极中山站的数字式电离层垂直测高仪1995年的频高图资料,对中山站上空冬季电离层的一些平均特性进行了初步分析。中山站冬季电离层F层很不稳定,其日变化比较明显,foF2的月中值在0900UT出现极大并在1400UT附近出现次极大。最大值在0900UT(磁中午)附近,这是极隙区软电子沉降、极区等离子体对流和光辐射电离效应等诸多因素综合作用的结果,形成了所谓的磁中午异常。在2000~0100UT之间foF2数值较小,可能是由于这段时间中山站正处于电离层极洞区域。Es层几乎每天都可以观测到,在1700UT附近出现机率较高,并且foEs数值较大,多数为极光型Es,主要是由于极光粒子沉降引起的。电离层E层的变化相对平缓。  相似文献   
20.
太阳活动低年南极中山站电离层F层的平均特性   总被引:9,自引:5,他引:4       下载免费PDF全文
根据1995-1997年3年中山站数字式电离层测高仪的数据,分析了中山站不同季 节F层的临频变化特点.中山站夏季主要受太阳光光化电离的影响,F层临频随地方时的变 化与中纬台站相似;两分季,极隙区软电子沉降的作用显著,F层临频随磁地方时而变化,有 较明显的磁中午现象.冬季,太阳全天处于地平线以下,中山站F层临频的变化主要受极隙 区软电子沉降和极区等离子体漂移的影响,其峰值变化处于碰中午和地方时中午之间.中山 站夏季全天都能观测到F层的存在;两分季F层在地方时子夜附近的出现率较少;冬季月份 在磁地方时午后和子夜F层出现率明显减少,这可能与南半球冬季的高纬槽和极洞有关.对 F层不均匀区的分析认为,中山站在t_(LT)为16:00左右处于极光带赤道侧,20:00左右进入极盖 区。  相似文献   
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