Mean ionospheric properties in winter at Zhongshan Station,Antarctica

ＭｅａｎｉｏｎｏｓｐｈｅｒｉｃｐｒｏｐｅｒｔｉｅｓｉｎｗｉｎｔｅｒａｔＺｏｎｇｓｈａｎＳｔａｔｉｏｎ，ＡｎｔａｒｃｔｉｃａTX＠刘顺林＠贺龙松＠刘瑞源ＭｅａｎｉｏｎｏｓｐｈｅｒｉｃｐｒｏｐｅｒｔｉｅｓｉｎｗｉｎｔｅｒａｔＺｈｏｎｇｓｈａｎＳｔａｔｉｏｎ，Ａｎ...     

Preliminary result of imaging riometer at Zhongshan Station, Antarctica

１ＩｎｔｒｏｄｕｃｔｉｏｎＺｈｏｎｇｓｈａｎＳｔａｔｉｏｎ（７６°２２′Ｅ,６９°２２′Ｓ）ｏｆＡｎｔａｒｃｔｉｃａｉｓｌｏｃａｔｅｄｉｎａｎｉｄｅａｐｌａｃｅｆｏｒｏｂｓｅｒｖｉｎｇｓｏｌａｒ－ｔｅｒｅｓｔｒｉａｌｐｈｅｎｏｍｅｎａ．ＡｔＺｈｏｎｇ...     

The characteristics of Pi2 pulsations at Zhongshan Station of Antarctica

In this paper Pi2 pulsations at Zhongshan Station of Antarctica are analyzed from October 1 - 31, 1996. Their characteristics e. g. occurrence frequency,frequency, and polarization are studied. The characteristics of Pi2 pulsations are summerized as follows: (1 ) Pi2 pulsations at Zhongshan Station usually take place from 2000 MLT to 0200 MLT; the main frequencies are between 6. 79 mHz and 13. 58mHZ; (2 ) Pi2 pulsations with low frequencies are dominent. The range of main frequencies becomes narrow at midnight; (3) The Polarization of Pi2 pulsations are almost linear; (4) About the orientation of major axes the NW-SE direction is dominent before 2200 MLT and NE-SW is dominent after 2200 MLT. The generation mechanism of Pi2 pulsations at Zhongshan Station is discussed theoretically.     

Polarization characteristics of Pc3 pulsations at Zhongshan Station of Antarctica

In this paper the data of geomagnetic pulsations at Zhongshan Station from February 3 to Novernber 30 in 1996 are analyzed in ordcr to study polarization characteristics of Zhongshan Station Pc3 pulsations which comprises the cusp Pc3 pulsation and the nightside Pc3 pulsation. For the cusp Pc3 pulsation. the right-handed polarization is always dominant. But their orientation of major axes of polarizations changes with season, NW-SE is dominant in summer and NE-SW in winter. For the nightside Pc3 pulsation,the right-handed with NE-SW is always dominant before midnight. But the left-handed with the mixing orientation of major axes is dominant in summer and the NE-SW with the mixing polarization sense is dominant in winter after midnight. It means that the two types of Zongshan Station Pc3 pulsations have different sources.     

Seasonal characteristics of F region in lower solar activity period at Zhongshan Station, Antarctica

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.     

Ionospheric absorption at Zhongshan Station, Antarctica during magnetic storms in early May, 1998

In the paper the high latitude ionospheric absorption events, monitored by an imaging riometer at Zhongshan Station, Antarctica, are examined during magnetic storms in early May, 1998. The storm absorption at ~0639 UT on May 2 was mainly an equatorward progressing absorption event, which were associated with a strong negative bay of the magnetic H component and with a large Pc3 range pulsation. There was a time lag of about 1. 5 hours between the onset of the ionospheric disturbance and the IMF southward turning in the solar wind. The event at 2222 UT on May 2 was a typical midnight absorption spike event. The absorption region took the form of an elongated strip with the length of 100 - 150 km and the width of 30 - 40 km. The absorption during 0830 - 1200 UT on May 6 was a polar cap absorption (PCA) event,caused by intense precipitation of high-energy protons erupted after a large solar flare explosion.     

Magnetotelluric sounding study in the region of Zhongshan Station，East Antarctica

ＭａｇｎｅｔｏｔｅｌｌｕｒｉｃｓｏｕｎｄｉｎｇｓｔｕｄｙｉｎｔｈｅｒｅｇｉｏｎｏｆＺｈｏｎｇｓｈａｎＳｔａｔｉｏｎ，ＥａｓｔＡｎｔａｒｃｔｉｃａＫｏｎｇＸｉａｎｇｒｕ（孔祥儒）ａｎｄＺｈａｎｇＪｉａｎｊｕｎ（张建军）（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｐｈ...     

南极长城站和中山站的近期气候变化及其对南极涛动的响应

利用长城和中山站的多种气象观测资料,揭示了南极气候在近15—30年全球气候变化关键时期的最新动态及其对南极涛动变化的响应。结果显示,近15年来,位于南极半岛地区的长城站增暖趋势减缓且有变冷迹象,并伴随气压下降和降水增多的趋势,表明全球增暖停滞期南极半岛经历了与过去几十年长期趋势有所不同的新变化,而位于南极大陆沿海的中山站气象要素变化趋势相对平缓,表明南极半岛和南极大陆气候变化特征存在显著的区域性差异。两站多个气象要素与南极涛动指数显著相关,两站温度与南极涛动相关关系相反等研究事实说明了两站气候与南极涛动及其对应的大气环流区域特征有着密切的联系。     

Comparison of temperature extremes between Zhongshan Station and Great Wall Station in Antarctica

Although temperature extremes have led to more and more disasters, there are as yet few studies on the extremes and many disagreements on temperature changes in Antarctica. Based on daily minimum, maximum, and mean air temperatures(Tmin, Tmax, Tmean) at Great Wall Station(GW) and Zhongshan Station(ZS), we compared the temperature extremes and revealed a strong warming trend in Tmin, a slight warming trend in Tmean, cooling in Tmax, a decreasing trend in the daily temperature range, and the typical characteristic of coreless winter temperature. There are different seasonal variabilities, with the least in summer. The continentality index and seasonality show that the marine air mass has more effect on GW than ZS. Following the terminology of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change(IPCC AR5), we defined nine indices of temperature extremes, based on the Antarctic geographical environment. Extreme-warm days have decreased, while extreme-warm nights have shown a nonsignificant trend. The number of melting days has increased at GW, while little change at ZS. More importantly, we have found inverse variations in temperature patterns between the two stations, which need further investigation into the dynamics of climate change in Antarctica.     

东南极夏季中山站邻近固定冰DMS、DMSP分布初探

中国第30次南极科学考察期间,在中山站邻近固定冰区采集了两支海冰冰芯并首次分析其中的DMS、DMSP含量。结果表明,两支冰芯上层均含有较高浓度的DMSP+DMS,分别高达114.93及134.41 nmol·L-1。冰芯中DMS、DMSP+DMS浓度随深度的增加而递减。两支冰芯顶部DMSP+DMS高值的成因不同,冰芯1主要受藻类活动影响而产生DMSP+DMS高值,冰芯2主要是由于雪层及薄冰层阻碍,致使DMS在冰芯顶部聚集产生DMS高值。因为海冰底部较高生物量的海冰融化进入水体,所观测的剩余海冰底部Chl a、DMSP+DMS值均较低。在海冰的融化过程中,卤道内的卤水可发生垂向运输,致使冰芯中Chl a、DMSP+DMS的垂直分布有所不同。冰芯的Chl a、DMSP+DMS总量分别为6.79和10.20、51.83和88.41μmol·m-2,与前人研究结果比较,在海冰融化过程中,海冰中Chl a、DMSP+DMS总量变化的总趋势是递减的。     

Intensity variations of the postnoon auroral bright spots observed at Zhongshan Station, Antarctica on August 8, 1999

In this paper we use the high speed multi channel meridian scanning photometer data and all sky 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)/I(630.0) and I(427.8)/I(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 above 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 multi band arcs.     

The digital mapping produced with satellite image of the Zhongshan Station area in Antarctica

ＴｈｅｄｉｇｉｔａｌｍａｐｐｉｎｇｐｒｏｄｕｃｅｄｗｉｔｈｓａｔｅｌｌｉｔｅｉｍａｇｅｏｆｔｈｅＺｈｏｎｇｓｈａｎＳｔａｔｉｏｎａｒｅａｉｎＡｎｔａｒｃｔｉｃａＳｕｎＪｉａｂｉｎｇ（孙家）ａｎｄＧａｎＸｉｎｚｈｅｎｇ（甘信铮）（ＷｕｈａｎＴｅｃｈｎｉ...     

A study on nano－ and microdiatoms in the intertidal zones of Zhongshan Station，Antarctica

Ａｓｔｕｄｙｏｎｎａｎｏ－ａｎｄｍｉｃｒｏｄｉａｔｏｍｓｉｎｔｈｅｉｎｔｅｒｔｉｄａｌｚｏｎｅｓｏｆＺｈｏｎｇｓｈａｎＳｔａｔｉｏｎ，ＡｎｔａｒｃｔｉｃａＺｈｕＧｅｎｈａｉ（朱根海）；ＬｕＤｏｕｄｉｎｇ（陆斗定）ａｎｄＷａｎｇＺｉｐａｎ（王自磐）（Ｓ...     

南极拉斯曼丘陵中山站地区Rb含量初步调查

利用手持快速矿石分析仪(NITON XL3t-500S GOLDD)对拉斯曼丘陵中山站附近出露的基岩进行测试, 初步调查结果显示该地区有明显的Rb元素富集。测试了17个样品, 其中12个的Rb含量达到了0.04%, 1个样品的Rb含量达到0.1%以上。分析测试样品特征, 并结合拉斯曼丘陵地质特征发现, 拉斯曼丘陵地区Rb的富集与含黑云母的泛非期伟晶岩墙关系密切, 而且粒度越大Rb含量越高, 类比推测该区域Rb元素富集潜力巨大, 有必要继续开展相应的地质调查工作, 进一步探讨其富集成因和规律。     

快速城镇化过程中的中国城镇土地利用特征

主要利用国土资源部土地利用变更调查数据, 从城镇土地数量、人均城镇土地、城镇 建设占地、城镇内部用地结构和城镇土地空间格局及其时空变化等方面分析了中国城镇化快 速发展阶段的城镇土地利用现状, 并将这一阶段的主要城镇土地利用问题归结为总量失控、 粗放利用、影响宏观经济平稳运行、影响耕地保护和粮食安全、危及社会和谐发展、土地利 用结构失调, 以及生态环境恶化等方面, 最后从合理引导城镇扩张并加强农地保护、优化区 域和城镇内部用地结构布局、多手段节约集约利用城镇土地、统筹协调区域城乡居民点建设 用地, 以及防治并举促进城镇土地生态良性化等角度探讨了城镇化健康发展的用地策略。     

基于工业结构特征的中国地区能源消费强度差异分析

本文从工业结构演变的角度分析地区能源消费强度差异,利用工业特征偏向指数对地区能源消费强度与工业结构之间的关系进行了定量分析,并通过建立地区能源消费强度影响因素的回归分析模型,重点考察了近几年中国地区工业结构能源消耗特征演变对地区能源消费强度差异的影响。研究表明,近几年来中国工业结构能耗特征的变化,对地区能源消费强度差异有重要影响。在中西部地区发挥资源和成本优势、大规模承接东部沿海地区产业转移的过程中,呈现出中西部地区工业结构高耗能化、东部地区工业结构低耗能化的演进态势,而高耗能的工业结构决定了较高的能源消费强度。政府在制定节能减排政策、进行节能目标分解时,要正确认识中西部地区工业结构演变的客观规律与发展阶段,根据各地区能源消费强度的变化特点,制定有区别的区域节能目标和政策措施。     

~(10)Be exposure ages of Quaternary Glaciers in Antarctica

In situ terrestrial cosmogenic nuclides(TCN) have been widely applied to date the ages of Quaternary glacial deposits in Antarctica and plays an important role in reconstructing the glacial evolution and climate change. It helps to understand the Antarctic ice sheet's evolution process in Quaternary and shed light on the application of Cosmogenic Nuclide exposure dating technique in glacial geomorphology. In this paper, we retrieved 49510 Be age samples in Antarctica from literature published between 2004 and 2020 and recalculated the TCN ages using version 3.0 online calculator of Cosmic-Ray Produced Nuclide Systematics on Earth(CRONUS-Earth). Several conclusions can be drawn from the results:(1) 75% of the exposure ages are younger than 400 ka, and 91% younger than 1, 100 ka. Northern Antarctic Peninsula exposure result is visibly younger than the main glaciers area in East Antarctica due to climate change and geological evaluation since the LGM(Last Glacial Maximum).(2) TCN ages are relevant to the samples' relative positions in the Antarctic continent, but a relationship between their ages and elevations is yet to be determined based on the collected data.     

Reconstruction of the Ross Ice Drainage System, Antarctica, at the Last Glacial Maximum

We present here a revised reconstruction of the Ross ice drainage system of Antarctica at the last glacial maximum (LGM) based on a recent convergence of terrestrial and marine data. The Ross drainage system includes all ice flowlines that enter the marine Ross Embayment. Today, it encompasses one-fourth of the ice-sheet surface, extending far inland into both East and West Antarctica. Grounding lines now situated in the inner Ross Embayment advanced seaward at the LGM (radiocarbon chronology in Denton and Marchant 2000 and in Hall and Denton 2000a, b), resulting in a thick grounded ice sheet across the Ross continental shelf. In response to this grounding in the Ross (and Weddell) Embayment, ice-surface elevations of the marine-based West Antarctic Ice Sheet were somewhat higher at the LGM than at present (Steig and White 1997; Borns et al. 1998; Ackert et al. 1999). At the same time, surface elevations of the East Antarctic Ice Sheet inland of the Transantarctic Mountains were slightly lower than now, except near outlet glaciers that were dammed by grounded ice in the Ross Embayment. The probable reason for this contrasting behavior is that lowered global sea level at the LGM, from growth of Northern Hemisphere ice sheets, caused widespread grounding of the marine portion of the Antarctic Ice Sheet, whereas decreased LGM accumulation led to slight surface lowering of the interior terrestrial ice sheet in East Antarctica. Rising sea level after the LGM tripped grounding-line recession in the Ross Embayment, which has probably continued to the present day (Conway et al. 1999). Hence, gravitational collapse of the grounded ice sheet from the Ross Embayment, accompanied by lowering of the interior West Antarctic ice surface and of outlet glaciers in the Transantarctic Mountains, occurred largely during the Holocene. At the same time, increased Holocene accumulation caused a slight rise of the inland East Antarctic ice surface.     

Ground－based measurements of column abundance of ozone and UV－B radiation over Zhongshan Station，Antarctica in the 1993＂OzoneHole＂

Ｇｒｏｕｎｄ－ｂａｓｅｄｍｅａｓｕｒｅｍｅｎｔｓｏｆｃｏｌｕｍｎａｂｕｎｄａｎｃｅｏｆｏｚｏｎｅａｎｄＵＶ－ＢｒａｄｉａｔｉｏｎｏｖｅｒＺｈｏｎｇｓｈａｎＳｔａｔｉｏｎ,Ａｎｔａｒｃｔｉｃａｉｎｔｈｅ１９９３＂ＯｚｏｎｅＨｏｌｅ＂ＺｈｏｕＸｉｕｊｉ（...