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1.
极地气象考察与全球变化研究   总被引:1,自引:0,他引:1  
南极和北极是地球上的气候敏感地区,也是多个国际计划研究全球气候变化的关键地区。极地包含了大气、海洋、陆地、冰雪和生物等多圈层相互作用的全部过程,在全球气候的形成和变化中有重要的作用。极地大气科学考察与研究是极地科学研究的重要组成部分。到2006年底,中国自主组织了23次南极考察,2次北冰洋考察和3次北极站考察;建成了南极长城站、中山站和北极黄河站,并在南极冰盖设置了3个无人自动气象站;开展了有关极地大气科学与全球变化的研究。在南北极地区,进一步加强国际合作,继续监测包括近地面温度在内的大气要素的变化,提高极地气象业务水平;拓展极地气象业务和大气科学考察研究领域,积极获取气候代用资料;进一步量化和认识极地在全球变化中的作用,及其对中国天气气候和国民经济可持续发展的影响;建立完善极地大气科学研究体系,提高极地大气科学研究水平,仍是中国极地大气科学与全球变化研究的重要内容之一。  相似文献   

2.
极地大气科学与全球变化研究进展   总被引:4,自引:0,他引:4       下载免费PDF全文
南极和北极是地球上的气候敏感地区, 也是多个国际科学计划研究全球气候变化的关键地区。极地大气科学考察与研究是极地科学研究的重要组成部分。中国气象科学研究院的极地大气科学考察与研究始于20世纪80年代, 25年来有较大进展。中国气象科学研究院参加了我国组织的23次南极考察、2次北冰洋考察和3次北极考察; 承担了南极长城站和中山站、北极黄河站气象业务建设和维持, 以及中-澳合作南极冰盖3个无人自动气象站工作; 进行了常规地面气象、Brewer大气臭氧、近地面物理、冰雪和大气化学等观测, 获得了较为系统的极地大气环境资料。开展了有关极地大气科学与全球变化的研究, 在极地天气气候特征及气候变化时空多样性、极地海冰变化和南极海冰涛动、极地近地面物理特征和海-冰-气相互作用、中山站臭氧变化特征及南极臭氧洞和大气化学、气候代用资料获取和古气候环境以及极地大气环境变化对东亚环流和中国天气气候影响等方面的研究取得了新进展。中国极地大气科学正积极通过多学科交叉、走国际合作道路, 努力提高对极地在全球变化中作用的认识水平, 并积极探索极地变化对我国气候、环境的影响。  相似文献   

3.
回顾了南极臭氧洞的发现过程,评述了南极臭氧洞形成和发展的机制、以及南北极臭氧变化的差异,讨论了南极臭氧洞的发现和研究带来的启示。研究指出,目前只是在南极春季出现了臭氧洞,北极并没有出现过臭氧洞。在当前大气环境被污染的情况下,极地大气臭氧亏损的程度将更多地随大气环流,特别是极地涡旋中的低温状况而发生变化。  相似文献   

4.
近20年来中国极地大气科学研究进展   总被引:14,自引:0,他引:14  
南极、北极和青藏高原是地球上的 3大气候敏感地区 ,是多个国际计划研究全球变化的关键地区。中国的南极和北极实地考察研究 ,分别始于 2 0世纪 80和 90年代 ,起步较晚 ,但近 2 0余年来有较大的进展。极地大气科学考察与研究是极地科学研究的重要组成部分。讫今为止 ,中国已组织了 2 0次南极考察和 3次北极考察 ,建立了中国南极长城站、中山站和北极黄河站等 3个常年科学考察站 ;进行了常规地面气象、Brewer大气臭氧、近地面物理、高层大气物理、冰雪和大气化学等观测 ,获得了较为系统的极地大气科学第一手资料 ;开展了有关极地与全球变化的研究 ,取得了新的进展。南极地区大气温度、臭氧和海冰的气候变化在时间和空间上都是多样的。南极地区的增暖主要发生在南极半岛地区 ,在南极大陆主体并不明显 ,近 10余年来还有降温趋势。中国南极长城站和中山站的观测资料也证实了这一点。此外 ,还揭示了南极半岛西侧和罗斯海外围的海冰变化具有“翘翘板”特征 ,由此定义的南极涛动指数可用来讨论南极海冰状况和海冰关键区的活动 ;用实地考察资料研究了极地不同下垫面的近地面物理和海 -冰 -气相互作用特征 ,给出了边界层特征参数 ;讨论了极地天气气候和大气环境特征及其对东亚大气环流和中国天气气候的影响 ;利用  相似文献   

5.
极地大气科学考察研究与展望   总被引:3,自引:0,他引:3  
高登义  邹捍  周立波 《大气科学》2008,32(4):882-892
本文包括四部分。第一部分是对中国科学院大气物理研究所1984年以来的极地大气科学考察研究工作概要地作了回顾;第二部分是中国科学院大气物理研究所近5年来在极地大气科学方面研究的主要进展;第三部分是对未来极地大气科学考察研究的重点问题的展望与建议;第四部分是结论与讨论。作者认为,未来极地大气科学考察研究的重点问题应该包括:(1)南极北极冰雪变化差异成因,(2)北极冰雪变化异常与我国气候变化关系,(3)南极冰雪变化与人类未来。  相似文献   

6.
地球北极和南极部分地区正在经历着以变暖和冰冻圈退缩为主要特征的显著变化,不仅深刻影响着当地生态环境和社会经济,而且具有半球乃至全球效应。IPCC在2019年9月发布的《气候变化中的海洋和冰冻圈特别报告》(SROCC)第三章对极地系统变化及其影响与适应做了系统评估,主要呈现了IPCC第五次评估报告(AR5)之后极地冰冻圈、海洋、生态和社会系统相互作用的最新科学认知,探讨了降低脆弱性和风险、增强适应性和恢复力的路径。文中对SROCC第三章进行扼要解读,主要内容包括:(1)极地海洋、海冰、积雪/冻土/淡水冰、冰盖与冰川等极地系统要素过去和未来变化及其影响以及极地与中低纬度天气气候之间的关联;(2)人类响应极地系统变化的策略和不足以及应对未来变化的不确定性;(3)当前加强极地恢复力建设的主要行动及其实施进展。  相似文献   

7.
南极臭氧洞对全球大气辐射加热场影响的数值模拟研究   总被引:2,自引:1,他引:1  
张弘  陈月娟  毕训强 《大气科学》1999,23(3):340-348
为了探讨南极臭氧洞对全球气候的影响状况,我们用IAP_9层全球大气环流模式进行了南极臭氧洞气候效应的数值试验。本文分析了本次试验中南极臭氧洞引起的大气辐射加热场的变化,结果表明,南半球高纬和极地平流层臭氧含量的严重减少,不仅影响该地的大气辐射加热场,同时也使北半球平流层大气的辐射加热场发生改变。虽然对流层中层所受影响较少,但对流层下层南北半球的大气总辐射加热率的变化却相当明显,这些影响将使全球大气温度场产生明显变化。  相似文献   

8.
南半球10 hPa极地涡旋的多尺度变化特征分析   总被引:1,自引:1,他引:0       下载免费PDF全文
利用NCEP/NCAR 10 hPa月平均高度场资料, 计算了1948\_2007年南半球10 hPa极地涡旋的强度指数P、 面积指数S和中心位置指数(λc, φc)。用它们分析了南半球10 hPa极地涡旋的季节变化、 年际异常及其可能成因, 分析了10 hPa极地涡旋强度与南极涛动的关系。结果表明: (1) 南半球10 hPa极区12月~1月受反气旋控制, 3~10月受气旋控制, 2月、 11月为环流转换季节。(2) 1(7)月反气旋(气旋)指数P\, S均在1970年代后期发生了显著的跃变; 跃变前反气旋(气旋)由极弱(极强)振荡地增强(减弱)至接近气候均值, 跃变后反气旋由极强振荡趋于气候均值, 气旋在偏弱的状态下振荡。(3) 1月反气旋中心位置存在显著的年代际变化, 而7月气旋中心位置的年际变化明显。(4) 臭氧异常可引起南半球10 hPa 1月极地反气旋年际异常(正相关), 但与7月极地气旋异常无关。(5) 1月、 7月极地涡旋强度指数P与南极涛动指数(AAOI)呈显著的负相关, 可由P来表征AAOI。  相似文献   

9.
季军 《青海气象》2007,(3):76-77
南极,熟悉而又陌生的名字,一个既神奇又神秘的地方,一块令人向往的冰雪世界,一块地球上没有受到人类破坏和污染的大陆。这一方净土,让许多人梦牵魂饶。作为第22次极地考察队的一员,我于2005年11月18日,从上海民生码头乘“雪龙”号极地考察船前往南极进行科学考察。经过1个月的长途航行,于2005年12月18日凌晨抵达南极。[第一段]  相似文献   

10.
1.引言极地平流层云(PSCs)对南极臭氧洞的形成及北半球臭氧的耗减是至关重要的.首先,极地平流层云通过沉降作用清除平流层中作为云的成分的氮化物.云层内低的氮化物含量,对高水平的活性氯物质的存在是极  相似文献   

11.
The accumulative profiles of seabird and sea animal excrement together with the depositional sequences influenced by the excrement have been utilized to reconstruct the historical populations of Antarctic penguins and seals, also to study the eco-geology in the ice-free areas of Antarctica and Arctic. The historical populations of Antarctic penguins show dramatic fluctuations, the period of sharp decrease coincides well with Neoglaciation, and extremely cold or warm climate conditions are unfavorable for the survival of Antarctic penguin. The historical change of seal population seems to be related to climatic variations, sea-ice coverage and its forage behavior. The fluctuations of Hg (mercury) in the seal hairs and the sediments influenced by seal excrement were found to be closely associated with ancient gold and silver mining activities and the ancient civilization over the past several thousand years.  相似文献   

12.
西藏普莫雍错位于喜马拉雅山脉印度季风雨影区,主要由冰川融水补给。根据湖泊的等深线分布和主要补给河流的入湖路径,对采自普莫雍错1~62 m水深范围的表层沉积物介形类和相关水环境参数进行了分析。结果表明,普莫雍错表层沉积物中含有7属9种介形类,其分布主要受湖泊水深、pH值、温度和光合有效辐射等环境因子的影响。介形类与水环境因子的降维对应分析、典型对应分析结果显示,水深是影响表层沉积物介形类分布的最重要的环境因子,用偏最小二乘法加权平均回归与校正模型建立的介形类-水深转换函数具有较高的精度与可靠性。利用此转换函数模型和一个72 cm长重力湖芯的介形类属种分析结果,定量重建了湖泊水深波动历史。湖面波动与湖芯的总有机碳、总无机碳、粒度等代用指标比较结果表明,普莫雍错6.0 kaBP以来的环境变化具有6.0~4.3 kaBP的温凉浅湖面期、4.3~2.0 kaBP温暖的湖面波动期及2.0 kaBP以来温暖的湖面扩张期。  相似文献   

13.
This paper summarizes the long-term fluctuations of snow accumulation in the Antarctic and analyzes its correlation with the sea level pressure (SLP) in the middle latitude (40°–50° S) of the Southern Hemisphere. Stratigraphic data which were compiled from studies on ice cores and snow-pits at eight stations in the Antarctic were used in the present study. It was found that the data concerning fluctuations in snow accumulation for East Antarctica showed correlations, whereas no such correlation was observed for the data from West Antarctica.This study shows possible relationships between snow accumulation in the Antarctic and SLP in the middle latitudes. The fluctuations of accumulation at South Pole, Dome C, Wilkes and South Ice Point show correlations with SLP over a large area in the 40°–50° S latitudinal zone. For the long-term fluctuations of SLP in the 40°–50 ° S latitudinal zone, a zonal fluctuation with wave number zero structure and a longitudinal variation of SLP anomalies due to their out-of-phase-fluctuation between the Pacific and the Indian Oceans were observed. The temporal scales for these fluctuations were found to be in the order of 20–30 years and 40–60 years, respectively. The influences of these two modes on the behaviour of snow accumulation in the Antarctic is also discussed.Now at Kitami Institute of Technology, Kitami, Hokkaido, Japan.  相似文献   

14.
This paper summarizes the long term and decadal time scale fluctuations of atmospheric circulation in the Southern(Hemisphere) middle and high latitudes.The long time series of Antarctic Oscillation Indices(AOIs) were established for January.April.July and October based on the historical sea level pressure maps and NCEP/NCAR reanalysis surface pressure data set.It was found that the AOI of January had upward trend at a rate of 1.17 hPa/100 a.and July haddownward trend at a rate of -1.49 hPa/100 a since 1871.The method of wavelet analysis wasapplied to detect the low frequency characteristics of AOIs,and it is clear that there are decadalvariations in the time scale of about 20-30 years in all 4 indices.Since the averaged value of 4months could explain most variance of annual AOI.thus it is reasonable using the mean AOI of January,April,July and October to represent the annual AOI.The value of annual AOI was much lower in periods of about 1894-1901.1910-1935,and was much higher in periods of about 1880-1893,1936-1945.The positive anomalies were remarkable since 1980s.Power spectra of modeled AOIs from Hadley Center Control Integration(HCCI) were compared with the observations,it is found that the interannual time scale frequencies were more significant than decadal frequencies.But.there also had the possibility for generating weak deeadal fluctuations in some special months and years by Hasselmann mechanism.  相似文献   

15.
The comparative analysis of hydrometeorological and topographic conditions of the formation and runoff of dense shelf waters on the shelves and continental slopes in different water areas of the Arctic and Antarctic demonstrates that they are similar in many aspects but there are some differences as well. In the Antarctic, these conditions are more favorable. The thermohaline conditions of the formation and runoff of shelf waters in the Arctic and Antarctic are also similar. The similarity of different conditions enables to construct the adaptive physical model of the shelf and slope cascading of shelf waters generalized for different polar water areas. It is based on the analysis of historical and present-day in situ data in the areas of margins of shelves and slopes in the Arctic and Antarctic, observations in the areas of flaw polynyas, and passing ice and meteorological observations, as well as on taking account of some general results of laboratory and theoretical investigations of the dense liquid runoff along the inclined bottom.  相似文献   

16.
南半球中高纬大气环流年代际变率的研究   总被引:3,自引:0,他引:3  
龚道溢  王绍武 《气象学报》2000,58(3):297-308
利用近百年全球海平面气压图和再分析海平面气压等资料,建立了自1871年以来1,4,7和10月份的南极涛动指数(AOI)序列。近百年来1月AOI有明显增强的趋势,7月AOI则有明显减弱的趋势。最近40多年来,1,4和10月AOI都有较强的上升趋势。4个月份的AOI都有20~30a左右的准周期波动,表现出显著的年代际尺度的变化。用1,4,7和10月的平均可以近似反映年平均南极涛动指数的变化。在年代际尺度上,年平均指数在1894~1901年、1910~1935年左右是强的负指数时期。1880~1893年、1936~1945年左右是较强的正指数时期,1980年代以来,强的正指数已经持续了近20a,且1990年代以来还有加强的趋势。模拟结果的功率谱显示气候系统内部产生的低频变化主要体现在年际尺度变率上,年代际尺度变率的谱值则远远低于观测结果,但不排除在个别情况下,通过Hasselmann机制产生AOI年代际变率的可能性。  相似文献   

17.
Four Holocene-long East Antarctic deuterium excess records are used to study past changes of the hydrological cycle in the Southern Hemisphere. We combine simple and complex isotopic models to quantify the relationships between Antarctic deuterium excess fluctuations and the sea surface temperature (SST) integrated over the moisture source areas for Antarctic snow. The common deuterium excess increasing trend during the first half of the Holocene is therefore interpreted in terms of a warming of the average ocean moisture source regions over this time. Available Southern Hemisphere SST records exhibit opposite trends at low latitudes (warming) and at high latitudes (cooling) during the Holocene. The agreement between the Antarctic deuterium excess and low-latitude SST trends supports the idea that the tropics dominate in providing moisture for Antarctic precipitation. The opposite trends in SSTs at low and high latitudes can potentially be explained by the decreasing obliquity during the Holocene inducing opposite trends in the local mean annual insolation between low and high latitudes. It also implies an increased latitudinal insolation gradient that in turn can maintain a stronger atmospheric circulation transporting more tropical moisture to Antarctica. This mechanism is supported by results from a mid-Holocene climate simulation performed using a coupled ocean-atmosphere model. Received: 7 July 1999 / Accepted: 21 July 2000  相似文献   

18.
Variations in production rates of warm North Atlantic Deep Water (NADW) have been proposed as a mechanism for linking climate fluctuations in the northern and southern hemispheres during the Pleistocene. We have tested this hypothesis by examining the sensitivity of a thermodynamic/dynamic model for Antarctic sea ice to changes in vertical ocean heat flux and comparing the simulations with modified CLIMAP sea-ice maps for 18 000 B.P. Results suggest that changes in NADW production rates, and the consequent changes in the vertical ocean heat flux in the Antarctic, can only account for about 20%–30% of the overall variance in Antarctic sea-ice extent. This conclusion has been validated against an independent geological data set involving a time series of sea-surface temperatures from the subantarctic. The latter comparison suggests that, although the overall influence of NADW is relatively minor, the linkage may be much more significant at the 41 000-year obliquity period. Despite some limitations in the models and geological data, we conclude that NADW variations may have played only a modest role in causing late Pleistocene climate change in the high latitudes of the southern hemisphere. Our conclusion is consistent with calculations by Manabe and Broccoli (1985) suggesting that atmospheric CO2 changes may be more important for linking the two hemispheres.  相似文献   

19.
Regular variation in the solid runoff of Antarctic glaciers with the period of 18.6 years is revealed as a result of long-term observations. It is demonstrated that the periodicity of the solid runoff correlates with the 18.6-year periodicity of the Earth’s angular velocity variations caused by the 18.6-year cyclicity of the variability of lunisolar tides. It is revealed that the vibratory gravitational sliding of glaciers to the sea is registered due to the tidal fluctuations along with many climate processes. The iceberg runoff lags as compared with the course of the variance of tidal fluctuations of the angular velocity approximately by six years.  相似文献   

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