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中国天山冰川区降水、积雪pH和电导率季节变化特征分析 总被引：1，自引：1，他引：0
根据乌鲁木齐河源区2003-2004年度的大气降水样品、1号冰川一个完整年周期的连续雪坑样品及哈密庙儿沟平顶冰川和奎屯51号冰川雪坑样品的pH和电导率资料,系统探讨大气降水、表层雪、雪坑样品中pH和电导率的季节变化特征和沉积过程中pH和电导率的变化特点,以及不同冰川区雪坑中pH值和电导率的空间差异。结果表明:大气降水及表层雪中pH和电导率有着相似的季节变化趋势,主要受冰川所在区域大气中可溶性离子浓度和沉积后过程的影响;对1号冰川大气降水、表层雪和雪坑样品中pH和电导率的对比分析发现,从降水到表层雪,最后到雪坑样品的演化过程中,pH和电导率均呈减小趋势,而且pH和电导率的最高值均出现在春季;自西向东随着地理环境的变化,雪坑中样品的pH值呈升高趋势,哈密庙尔沟平顶冰川最大,乌鲁木齐河源1号冰川次之,奎屯哈希勒根51号冰川最小,但电导率却呈现出了不同的变化规律。 相似文献
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积雪淋溶作用对冰川雪层内主要阴、阳离子记录的影响 总被引：12，自引：0，他引：12
利用乌鲁木齐河源１号冰川初始消融季节的连续雪坑离子浓度剖面,初步探讨本区冰川雪层中离子淋溶作用的特征及其对雪冰化学记录的影响。结果表明原始积雪内的大部分化学成分随融水向下渗浸,并富集在雪／冰界面处或附加冰内。当冰川消融进一步加剧,导致大部分离子成分随融水进入冰川径流,则会最终形成离子浓度很低的冰川冰,冰芯之定量记录将蜕变为定性结果。 相似文献
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天山东部冰川积雪中大气粉尘的沉积特征 总被引：3，自引：0，他引：3
对我国天山东部三个研究点乌鲁木齐河源1号冰川、奎屯哈希勒根51号冰川和哈密庙尔沟平顶冰川积雪中大气粉尘沉积进行了分析研究。微粒特征分析表明,自西向东随着研究点地理环境的变化,积雪中不溶微粒的质量浓度、沉积通量和体积粒径分布众数都表现出增高趋势：奎屯哈希勒根51号冰川最小,乌鲁木齐河源1号冰川次之,哈密庙尔沟平顶冰川最大;三个研究点粒径0．57〈d〈26μm微粒的平均质量浓度分别是969μg／kg、1442μg／kg、3690μg／kg,年均沉积通量分别是58．2μg／cm^2、72．1μg／cm^2、73．8μg／cm^2。表明,哈密冰川受粉尘源影响较大．而乌鲁木齐河源与奎屯河源区受影响则相对较小。雪坑微粒浓度剖面和离子相关性分析表明,天山东部冰川积雪中污化层富含亚洲粉尘的富Ca^2＋、Na^2＋矿物;微粒体积一粒径分布众数介于3-22μm．粒径分布显示了单结构模式。研究区最近4年积雪的污化层剖面揭示了春季零星的粉尘浓度峰值以及沉积数量上较大的年际变化,意味着天山东部雪冰中粉尘沉积对大气环境变化的敏感性。 相似文献
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北极Ｓｖａｌｂａｒｄ群岛Ｌｏｎｇｙｅａｒｂｙｅｎ地区３条冰川８个雪坑样品的分析结果表明,该地区冰川表层雪中海盐离子Ｃｌ－和Ｎａ＋占主导地位,其浓度远高于其它离子,而陆源Ｃａ２＋在雪坑秋季污化层中浓度远远高于其它层位,可作为雪坑定年中秋季层位的标志。在季节变化上,海盐离子和ＳＯ２－４、ＮＯ－３在春季和夏季表现为高值,这与冬春季节北大西洋风暴和中纬度人类污染物远距离传输到北极有关,也与夏季局地海洋性气团、大气中氧化作用、光电作用和清除速率有关。同全球的边远地区格陵兰、南极和青藏高原比较,Ｌｏｎｇｙｅａｒｂｙｅｎ地区雪中离子浓度水平较高,特别是海盐离子浓度远高于其它地区。 相似文献
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天山乌鲁木齐河源1号冰川的气候敏感性研究 总被引：6，自引：1，他引：5
依据山地冰川规模对于气候变化平衡态响应的一种统计模型,探讨了天山乌鲁木齐河源１号冰川东,西支在不同气候情景下的平衡态规模大小,根据该冰川的历史变化并应用这一统计模型,对于乌鲁木齐河源地区气候变化的趋势进行了研究。 相似文献
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天山东部冰芯pH值和电导率的大气环境空间差异 总被引：2，自引：1，他引：1
冰芯电导率是大气环境变化的替代性指标.对我国天山东部三个研究点奎屯哈希勒根48号冰川、乌鲁木齐河源1号冰川以及哈密庙儿沟平顶冰川粒雪芯中pH值和电导率的近期环境记录进行了分析研究.结果显示,三个研究点粒雪芯反映的近期pH值和电导率变化趋势不同:奎屯电导率随冰芯深度增加表现出升高趋势,哈密庙尔沟平顶冰川和乌鲁木齐河源1号冰川随冰芯深度增加表现出一定下降趋势;冰芯电导率平均值在哈密庙儿沟冰川最大,而其他两个点相对较小,这与矿物粉尘浓度和离子浓度的分布一致;雪冰电导率与粉尘及离子相关性分析表明,电导率主要受中亚粉尘活动影响,同时与Ca2+、Mg2+、Na+等相关性很高.通过比较显示,天山东部与我国西部其他研究点以及极地雪冰电导率的差异可以很好地反映大气环境的空间差异. 相似文献
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冰川及其径流对气候变化响应过程的模拟模型 总被引：3，自引：0，他引：3
用冰川动力模型对乌鲁木齐河源１号冰种东支进行模拟计算结果表明：１号冰川东支在维持目前气候变化水平下还将继续退缩到约１６００ｍ长度，若气温升高１℃，１号冰川将退缩为约只有３００ｍ长的悬冰川。 相似文献
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利用极光全天空摄象机１９９５年和１９９７年在南极中山站观测的极光数据,对中山站上空极光的出现情况进行了统计分析。在南极中山站,午后（磁地方时１４００～１８００ＭＬＴ）和子夜前后（２２００～０３００ＭＬＴ）出现极光的情况比较多,在傍晚（１８００～２２００ＭＬＴ）出现极光的情况要少一些;较强的极光主要也出现在午后和子夜附近。冕状极光主要出现在子夜附近和午后的极向侧和天顶,在傍晚出现很少;带状极光主要出现在午后和赤道侧的傍晚与子夜;极光浪涌主要出现在子夜前后;向日极光弧则主要出现在子夜前后,子夜前比子夜后多,极向和天顶比赤道侧多。除向日极光弧外,其它形态的极光在中山站的出现情况与Ｋｐ指数相关。中山站进入极光带的时间通常在午后,具体时间也与Ｋｐ指数有关 相似文献
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The auroral data observed by all sky TV camera during 1995 and 1997 at Zhongshan Station of Antarctica are used to analyze the statistic characteristics of the aurora over Zhongshan Station. Around postnoon (1200 - 1600UT ) and midnight (2000 - 0100 UT ), the aurora appears more frequently and stronger than those in evening (1600- 2000UT ). The corona type auroras mainly occur at poleward and overhead of Zhongshan Station during postnoon and around midnight. The hand type auroras mainly appear during postnoon. while during evening and around midnight only appear at equatorward. The active surges mostly appear around midnight,while the transpolar arcs mainly occur after midnight. Except for the transpolar arcs. the occurrences of the other three type auroras are related with Kp index. Usually Zhongshan Station enters the auroral oval at postnoon,the exact time depends on Kp index. 相似文献
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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 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
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Day-side aurora phenomena are examined by using TV image data obtained at Ny-Alesund in Svalbard, Godhavn in Greenland and Zhongshan Station,Antarctica. Results are summarized as follows. During the quiet period, in the pre-and post-noon sectors. (1) Weak arc (Sun-aligned arc), (2) Corona aurora and (3) Band aurora are observed in these stations. During disturbed period,Corona aurora and Band aurora are also observed in the pre- and post-noon sectors. However. bright discrete aurora. instead of weak arc (Sun-aligned arc). develops from thc night side oval in the dawn and dusk sectors. Pre-noon corona and post-noon band aurora are observed in the lower latitude as compared with the location of those auroras during the quiet period. 相似文献
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本文利用北极黄河站三波段全天空成像仪（ASI）的高分辨率的地面极光观测数据,联合欧洲非相干散射雷达（EISCAT）Svalbard雷达（ESR）,超级双子极光雷达网（SuperDARN）雷达等观测,研究了发生在2003年12月22日0900-1010 UT时间段内极区电离层极光和等离子体的变化特征。研究发现在不同行星际磁场（IMF）条件下,黄河站极光ASI均观测到了一系列极向运动极光结构（PMAFs）,其特征为极光在赤道向一侧点亮后向高纬扩展。这些PMAFs都伴随有明显的粒子沉降特征,且在IMF北向时该粒子沉降能达到更低的电离层E层区域,而此时这些PMAFs相应位置的高纬电离层出现了一个典型反向对流涡,这是高纬（尾瓣）重联的典型特征之一。这些结果表明北向IMF条件下的这些PMAFs是由高纬重联所产生。在IMF南向时,黄河站观测到的PMAFs可跨越更广的地磁纬度,表明其演化时间亦较长,其相应区域的电离层特征也表明该PMAFs由日侧磁层顶低纬磁重联所产生。 相似文献
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Seasonal characteristics of F region in lower solar activity period at Zhongshan Station, Antarctica 
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下载免费PDF全文 Based on data of Digisonde Portable Sounder-4 (DPS-4 ) in 1995 -1997. we have analyzed the seasonal variations of F region at Zhongshan Station (69. 4°S,76. 4°E ). During the summer of Zhongshan Station, F region ionization is mainly controlled by the solar ultraviolet radiation. Similar to the phenomena in mid-latitude area, the value f0F2 is changed with local time. During equinox scasons, soft electron precipitation from the cusp/cleft region seems significant, f0F2 is changed with rnagnetic local time, and shows the magnetic noon phenomenon. In winter. the effect of the solar radiation on the F region is less than that of summer. Instead, F region is affected by particle precipitation from cusp/cleft region as well as polar plasma convection, there fore, the diurnal variation of f0F2 is more complex and shows two peaks. F region occurs all day in summer. and seldom appears at midnight in equinox.In winter, F region shows two minimums, one is at midnight and the other is at afternoon cusp. Further analysis of the F region spread indicates that in winter the aurora oval passes over the Zhongshan Station is at 1100 UT - 1500 UT. 相似文献
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介绍了成像式宇宙噪声接收机在中山站的部署,分析了首批观测数据,得出中山站区宇宙噪声静日曲线。分析表明,观测期间中山站区的宇宙噪声吸收事件夜间与白天显著不同。在夜间,吸收事件呈脉冲式,持续时间为数分钟,吸收区域常在站区北侧出现,沿东西方向伸展;在磁中午附近,吸收事件持续时间在１小时以上,吸收区域南北侧较强,中央较弱。可以认为,夜间吸收区域对应着极光带,其吸收由极光粒子沉降引起;在磁中午,吸收区域对应着极隙区,其吸收可能与极隙区粒子沉降和对流有关。 相似文献
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通过观测的极光与地磁扰动之间关系的分析,初步得出了南极中山站夜间（１１～２４ＵＴ左右）强、中、弱极光出现的频次在时间上的分布规律与地磁场扰动的关系,弱极光１０时开始出现, １５时左右频次达到高峰;中等极光１１时开始,１２到１９时出现的频次平稳, ２１到２２时频次达到高峰;强极光１６时开始, ２０到２１时极光频次达到高峰。各类极光出现的频次在时间上的分布与其所对应的地磁场扰动基本上是一致的,弱极光伴随着地磁场扰动幅度小;强极光伴随着地磁场扰动幅度大。极光的开始时间和地磁场扰动的时间不完全对应,这与极光的变化状态有关,这种变化状态受复杂的空间物理过程控制。 相似文献
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The vertical temperature profiles of snow and sea ice have been measured in the Arctic during the 2nd Chinese National Arctic Research Expedition in 2003(CHINARE2003).The high-resolution temperature profile in snow is solved by one-dimensional heat transfer equation.The effective heat diffusivity,internal heat sources are identified.The internal heat source refers to the penetrated solar radiation which usually warms the lower part of the snow layer in summer.By temperature gradient analysis,the zero level can be clarified quantitatively as the boundary of the dry and wet snow.According to the in situ time series of vertical temperature profile,the time series of water content in snow is obtained based on an evaluation method of snow water content associated with the snow and ice physical parameters.The relationship of snow water content and snow temperature and temporal-spatial distribution of snow water content are presented 相似文献
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《极地研究》2002,13(1):67-74
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, but 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. 相似文献