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61.
In this paper we document the correlationship between sea surface temperature(SST) and low level-winds such as sea level wind and 850 hPa wind in the South China Sea(SCS) based on COADS(1958-1987) and ECMWF objective analysis data(1973-1986).Further statistical analyses tell us that there is a fixed SCS basin mode for variations both of SST and low-level winds in the region on the interannual time scale due to air-sea interactions.A simplified,coupled model that is designed following the McCreary and Anderson's(1985) model and includes the feedback between the upper ocean and the circulation of East Asian monsoon demonstrates an interannual oscillation in the coupled air-sea system,which is similar to the observations in the SCS. 相似文献
62.
泥炭档案气候变化重建的定量模型 总被引:3,自引:1,他引:3
泥炭档案气候变化重建的定量模型*陶发祥洪业汤(中国科学院地球化学研究所,贵阳550002)李汉鼎冷雪天(东北师范大学地理系,长春130024)关键词泥炭档案纤维素稳定同位素气候变化定量模型用泥炭档案定量重建大气CO2浓度的研究已取得重要进展[1],但... 相似文献
63.
Tan Ming Qin Xiaoguang Liu Tungsheng Laboratory of Speleothem Paleoclimatology Institute of Geology CAS Beijing People’s Republic of China 《地理学报(英文版)》1997,(3)
I.IntroductionStalagmiteshavebeenappliedtouseashighresolutionpaleoclimaticindicatorssincetheannualgrowthbandingwasrecognizedinstalagmites[1,2].Annualgrowthbandingcanbemanifestedinseveralmannersdefinedby1)alternatingfluorescentandnon-fluorescentcalcite[3,4];2)… 相似文献
64.
柴达木盆地西部新生代气候与地形演变 总被引:24,自引:0,他引:24
从孢粉植物分异及演变,干旱碎屑及膏盐沉积分布等方面,对柴达木盆地西部新生代气候与地形的演变进行了探讨。结果表明,盆地西部新生代两个极端干燥气候期(膏盐发育期)分别出现在始新世至渐新世及上新世至第四纪。前者与老第三纪行星环流控制下的副热带干燥带有关,而后者与青藏高原的隆升有关。早第三纪盆地西部及周围地区的地势不象以前所认为的那么低平。在第三纪,昆仑山比祁连山低。晚新生代盆地向北推移了7-11个纬距。 相似文献
65.
在中欧地区的河谷、洪积扇、山坡坡麓及湖底常零星分布着更新世及全新世的碳酸盐沉积物。不少学者把碳酸盐沉积当作气候变化的产物并划分出其在中欧沉积的若干时期。笔者通过德国中部Leine河流域新老石灰泉华的详细研究对泉华沉积与气候直接联系的观点提出了新的见解。运用不同方法测年验证,得知研究区的石灰泉华沉积始于11000aB.P,随后石灰泉华在研究区不同地点连续沉积。岩芯上沉积的变化和石灰泉华层的消失应是由地貌过程所引起的泉水出露位置改变所致。 相似文献
66.
塔里木及邻区晚古生代早期古气候与构造 总被引:2,自引:0,他引:2
影响塔里木及邻区晚古生代早期气候的地球内部因素为古昆仑和南天山两个古洋盆封闭及有关的两条缝合构造带演化,从而形成上述时空段内热带海洋气候、热(亚热)带季风气候、热带沙漠气候以及热带滨岸干湿气候区域的更替,古气候特征的判断主要依据古地磁数据、古生态气候学、沉积环境诸方面。 相似文献
67.
68.
This paper deals with dissolved inorganic carbon (DIC) and organic carbon (DOC) in pore waters from a 150 m deep hole drilled through the carbonate barrier reef of Tahiti and its underlying basalt basement. Alkalinity-pH measurements were used to calculate the DIC species concentration, and DOC was analysed according to the high temperature catalytic oxidation technique. Salinity was used as a conservative tracer to help identify water origin and mixing within the hole. Water mixing, calcium carbonate dissolution and mineralization of organic carbon combined to form three distinct groups of pore water. In the deeper basalt layers, pore water with alkalinity of 1.4 meq kg–1 pH of 7.6 and p(CO2) of 1.2 mAtm was undersaturated with respect to both aragonite and calcite. In the intermediate carbonate layer, pore water with alkalinity of more than 2.0 meq kg–1, pH of 7.70 and p(CO2) of 1.4 mAtm was supersaturated with respect to both aragonite and calcite. The transition zone between those two groups extended between 80 and 100 m depth. The shift from aragonite undersaturation to supersaturation was mainly attributed to the mixing of undersaturated pore waters from the basalt basement with supersaturated pore waters from the overlaying limestone. In the top of the reef, inputs from a brackish water lens further increased p(CO2) up to 5.6 times the atmospheric P(CO2). 相似文献
69.
HanBin Xue René Gächter Laura Sigg 《Aquatic Sciences - Research Across Boundaries》1997,59(2):176-189
Data on the cycling of Cu and Zn in two eutrophic lakes are presented: Lake Greifen that becomes seasonally anoxic in its
hypolimnion and Lake Sempach that is aerated during winter and oxygenated during summer. They suggest that hypolimnetic oxygenation
1) enhances the release of copper from the sediment but 2) also accelerates the entrapment and deposition of Cu and Zn by
freshly formed Mn- and Fe-oxides. 相似文献
70.
The temporal and spatial characteristics of the surface air temperature variations over the Antarctic and its surrounding area 总被引:1,自引:0,他引:1
The characteristics of the spatial distribution, temporal variations trend and oscillation for the surface air temperature
variations during 1957—1993 in the Antarctic and its surrounding area were analyzed. The results show that the short-time
climate change in the Antarctic is complex both temporally and spatially. The Antarctic is by no means the strongest responding
region to the global greenhouse effect. There is a distinguished difference in the trends of the temperature changes for the
Antarctic and global mean, which could not be explained simply by the global greenhouse effect.
Project supported by the National Antarctic Key Project of China (85-905). 相似文献