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Recent glacial retreat in High Asia in China and its impact on water resource in Northwest China 被引量:122
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作者 YAO Tandong 1,2 ,WANG Youqing 2 ,LIU Shiying 2,1 ,PU Jianchen 2,1 ,SHEN Yongping 2 & LU Anxin 2,1 1.Institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100029,China 2.Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou 730000,China 《Science China Earth Sciences》 SCIE EI CAS 2004年第12期1065-1075,共11页
Under the impact of climatic warming, the glaciers in the High Asia in China have been retreating continuously with negative glacial mass balance in recent several decades. The retreat became more intensive in the pas... Under the impact of climatic warming, the glaciers in the High Asia in China have been retreating continuously with negative glacial mass balance in recent several decades. The retreat became more intensive in the past 10 years. The spatial pattern of the glacial retreat in the High Asia in China is that the smallest magnitude of retreat is in the inland of the Tibetan Plateau, the magnitude increases from the inland to the margin of the Tibetan Plateau, and the largest magnitude at the margin of the Tibetan Plateau. The glacial retreat in the High Asia in China has an important impact on the water resource of the arid regions in Northwest China. This study shows that the glacial retreat in the 1990s has caused an increase of 5.5% in river runoff in Northwest China. In the Tarim River basin, the increase of river runoff is higher than 5.5%. 展开更多
关键词 HIGH Asia glacial fluctuation IMPACT on water resource.
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Variations in temperature and precipitation in the past 2000 a on the Xizang (Tibet) Plateau——Guliya ice core record 被引量:46
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作者 姚檀栋 L.G.Thompson +4 位作者 秦大河 田立德 焦克勤 杨志红 谢超 《Science China Earth Sciences》 SCIE EI CAS 1996年第4期425-433,共9页
The past temperature and precipitation variations are recorded precisely and continuously in μ18O and glacial accumulation records in the Guliya ice core. Fight warm periods and seven cold periods can be distinguishe... The past temperature and precipitation variations are recorded precisely and continuously in μ18O and glacial accumulation records in the Guliya ice core. Fight warm periods and seven cold periods can be distinguished in the past 2000 a. Of the four most intensive cold periods, three are in the Little Ice Age and one in the 11th - 12th century. The variation of precipitation is relatively small compared with that of temperature. Five humid periods and four dry periods occurred in the past 2 000 a. The long-term variation of temperature is positively correlated with that of precipitation according to the Guliya ice core record, but the variation of precipitation lags behind the variation of temperature. 展开更多
关键词 Guliya ice core δ^(18)O glacial accumulation.
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Transition of Quaternary glacial cyclicity in deep-sea records at Nansha,the South China Sea 被引量:37
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作者 汪品先 田军 成鑫荣 《Science China Earth Sciences》 SCIE EI CAS 2001年第10期926-933,共8页
High-resolution oxygen isotope records over the last 2249 ka (MIS 1-86) have been obtained from cores of the upper section (105.08 m) at ODP Site 1143 (water depth of 2772 m)drilled in the Nansha area, southern South ... High-resolution oxygen isotope records over the last 2249 ka (MIS 1-86) have been obtained from cores of the upper section (105.08 m) at ODP Site 1143 (water depth of 2772 m)drilled in the Nansha area, southern South China Sea. The sampling resolution is at about 2 ka intervals, resulting in one of the best oxygen isotope records over the global ocean. The oxygen isotope curves, displaying details in the Pleistocene glacial cycles, have revealed a nearly 300 ka long stage of transition from a predominant 40 ka to 100 ka periodicity. Therefore, the 'Mid-Pleistocene Revolution' should be considered as a process of transition rather than an abrupt change. Within the 100 ka glacial cycles, the changes in tropical sea surface water were found to lead those in high-latitude ice sheet. Our comparisons show that the ice sheet expansion and the glacial stage extension in the Northern Hemisphere with the 100 ka cycles must have been driven not by ice sheet itself, but by processes outside the high latitudes of the Northern Hemisphere. 展开更多
关键词 QUATERNARY glacial cycles Mid-Pleistocene Revolution oxygen isotope stages Nansha area
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Glacial change in the vicinity of Mt. Qomolangma (Everest), central high Himalayas since 1976 被引量:25
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作者 NIE Yong ZHANG Yili +1 位作者 LIU Linshan ZHANG Jiping 《Journal of Geographical Sciences》 SCIE CSCD 2010年第5期667-686,共20页
Glaciers are one of the most important land covers in alpine regions and especially sensitive to global climate change. Remote sensing has proved to be the best method of investigating the extent of glacial variations... Glaciers are one of the most important land covers in alpine regions and especially sensitive to global climate change. Remote sensing has proved to be the best method of investigating the extent of glacial variations in remote mountainous areas. Using Landsat thematic mapping (TM) and multi-spectral-scanner (MSS) images from Mt. Qomolangma (Everest) National Nature Preserve (QNNP), central high Himalayas for 1976, 1988 and 2006 we derived glacial extent for these three periods. A combination of object-oriented image interpretation methods, expert knowledge rules and field surveys were employed. Results showed that (1) the glacial area in 2006 was 2710.17 + 0.011 km2 (about 7.41% of the whole study area), and located mainly to the south and between 4700 m to 6800 m above sea level; (2) from 1976 to 2006, glaciers reduced by 501.91± 0.035 km2 and glacial lakes expanded by 36.88 + 0.035 kin2; the rate of glacier retreat was higher in sub-basins on the southern slopes (16.79%) of the Himalayas than on the northern slopes (14.40%); most glaciers retreated, and mainly occurred at an elevation of 4700-6400 m, and the estimated upper limit of the retreat zone is between 6600 m and 6700 m; (3) increase in temperature and decrease in precipitation over the study period are the key factors driving retreat. 展开更多
关键词 glacial change glacial retreat HIMALAYAS Mt. Qomolangma (Everest) National Nature Preserve remote sensing
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In situ cosmogenic ^(10)Be dating of the Quaternary glaciations in the southern Shaluli Mountain on the Southeastern Tibetan Plateau 被引量:26
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作者 Raisbeck Grand Yiou Francios 《Science China Earth Sciences》 SCIE EI CAS 2006年第12期1291-1298,共8页
It is generally considered that four-times ice age happened during the Quaternary epoch on the Tibetan Plateau. However, the research on the chronology of the four-times ice age is far from enough. The Shaluli Mountai... It is generally considered that four-times ice age happened during the Quaternary epoch on the Tibetan Plateau. However, the research on the chronology of the four-times ice age is far from enough. The Shaluli Mountain on the Southeastern Tibetan Plateau is an ideal place for plaeo-glacier study, because there are abundant Quaternary glacial remains there. This paper discusses the ages of the Quaternary glaciations, based on the exposure dating of roche moutonnée, moraines and gla- cial erosion surfaces using in situ cosmogenic isotopes 10Be. It is found that the exposure age of the roche moutonnée at Tuershan is 15 ka, corresponding to Stage 2 of the deep-sea oxygen isotope, suggesting that the roche moutonnée at Tuershan is formed in the last glacial maximum. The expo- sure age of glacial erosion surface at Laolinkou is 130―160 ka, corresponding to Stage 6 of the deep-sea oxygen isotope. The oldest end moraine at Kuzhaori may form at 421―766 kaBP, corre- sponding to Stages 12―18 of the deep-sea oxygen isotope. In accordance with the climate charac- teristic of stages 12,14,16 and 18 reflected by the deep-sea oxygen isotope, polar ice cores and loess sequence, the oldest end moraine at Kuzhaori may form at stage 12 or stage 16, the latter is more possible. 展开更多
关键词 Quaternary glaciation glacial cosmogenic isotope dating 10Be exposure dating Tibetan Plateau environmental change surface dating boulder erosion.
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Reconstruction of paleocoastlines for the northwestern South China Sea since the Last Glacial Maximum 被引量:18
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作者 HARFF Jan MEYER Michael 《Science China Earth Sciences》 SCIE EI CAS 2009年第8期1127-1136,共10页
The range of relative sea level rise in the northwestern South China Sea since the Last Glacial Maximum was over 100 m. As a result, lowland regions including the Northeast Vietnam coast, Beibu Gulf, and South China c... The range of relative sea level rise in the northwestern South China Sea since the Last Glacial Maximum was over 100 m. As a result, lowland regions including the Northeast Vietnam coast, Beibu Gulf, and South China coast experienced an evolution from land to sea. Based on the principle of reconstructing paleogeography and using recent digital elevation model, relative sea level curves, and sediment accumulation data, this paper presents a series of paleogeographic scenarios back to 20 cal. ka BP for the northwestern South China Sea. The scenarios demonstrate the entire process of coastline changes for the area of interest. During the late glacial period from 20 to 15 cal. ka BP, coastline slowly retreated, causing a land loss of only 1×104 km2, and thus the land-sea distribution remained nearly unchanged. Later in 15-10 cal. ka BP coastline rapidly retreated and area of land loss was up to 24×104 km2, causing lowlands around Northeast Vietnam and South China soon to be underwater. Coastline retreat continued quite rapidly during the early Holocene. From 10 to 6 cal. ka BP land area had decreased by 9×104 km2, and during that process the Qiongzhou Strait completely opened up. Since the mid Holocene, main controls on coastline change are from vertical crustal movements and sedimentation. Transgression was surpassed by regression, resulting in a land accretion of about 10×104 km2. 展开更多
关键词 relative SEA level change paleocoastline RECONSTRUCTION LAST glacial Maximum NORTHWESTERN South China SEA
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Repeated Range Expansion and Glacial Endurance of Potentilla glabra(Rosaceae) in the Qinghai-Tibetan Plateau 被引量:15
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作者 Liu-Yang Wang Hiroshi Ikeda +2 位作者 Teng-Liang Liu Yu-Jin Wang Jian-Quan Liu 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2009年第7期698-706,共9页
To date, little is still known about how alpine species occurring in the Qinghai-Tibetan Plateau (QTP) responded to past climatic oscillations. Here, by using variations of the chloroplast trnT-L, we examined the ge... To date, little is still known about how alpine species occurring in the Qinghai-Tibetan Plateau (QTP) responded to past climatic oscillations. Here, by using variations of the chloroplast trnT-L, we examined the genetic distribution pattern of 101 individuals of Potentilla glabra, comprising both the interior QTP and the plateau edge. Phylogenetic and network analyses of 31 recovered haplotypes identified three tentative clades (A, B and C). Analysis of molecular variance (AMOVA) revealed that most of the genetic variability was found within populations (0.693), while differentiations between populations were obviously distinct (Fst -- 0.307). Two independent range expansions within clades A and B occurring at approximately 316 and 201 thousand years ago (kya) were recovered from the hierarchical mismatch analysis, and these two expansions were also confirmed by Fu's Fs values and 'g' tests. However, distant distributions of clade C and private haplotypes from clades A and B suggest that they had survived the Last Glacial Maximum (LGM) and previous glaciers in situ since their origins. Our findings based on available limited samples support that multiple refugia of a few cold-enduring species had been maintained in the QTP platform during LGM and/or previous glacial stages. 展开更多
关键词 glacial refugia PHYLOGEOGRAPHY Potentilla glabra Qinghai-Tibetan Plateau range expansion tmT-L.
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AMS dating on glacial tills at the source area of the Urumqi River in the Tianshan Mountains and its implications 被引量:15
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作者 Chaolu Yi Kexing Liu Zhijiu Cui 《Chinese Science Bulletin》 SCIE EI CAS 1998年第20期1749-1751,共3页
Using accelerating mass spectrometry (AMS) dating method, a dating has been made on the primary calcium carbonate in tills and secondary calcium carbonate coating on till gravel and the roche moutonnee formed since th... Using accelerating mass spectrometry (AMS) dating method, a dating has been made on the primary calcium carbonate in tills and secondary calcium carbonate coating on till gravel and the roche moutonnee formed since the Last Glaciation at the source area of the Urumqi River valley in the Tianshan Mountains, northwestern China. The results reveal that the carbonate content in the tills in this noncarbonate area is high enough to date by AMS, that the carbon in the coatings on the newly exposed roche moutons and in the modern till is modern carbon and so the 14 C dating results in the ancient till can represent the actual ages of the till formation, and that the warm period during the Holocene began as early as 6 500 a B.P. and lasted to 1 800 a B.P. 展开更多
关键词 AMS DATING glacial TILL TIANSHAN Mountains.
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Quaternary glacial geomorphology and glaciations of Kongur Mountain,eastern Pamir,China 被引量:17
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作者 WANG Jie ZHOU ShangZhe +2 位作者 ZHAO JingDong ZHENG JingXiong GUO XiangZhong 《Science China Earth Sciences》 SCIE EI CAS 2011年第4期591-602,共12页
Kongur Mountain is the largest center of modern glaciation on the Pamir Plateau.During the glacial-interglacial cycles of the Quaternary,Kongur Mountain was extensively and repeatedly glaciated,and the glacial landfor... Kongur Mountain is the largest center of modern glaciation on the Pamir Plateau.During the glacial-interglacial cycles of the Quaternary,Kongur Mountain was extensively and repeatedly glaciated,and the glacial landforms from multiple glaciations are well-preserved in valleys,in basins,and on the piedmonts.Dating samples have been collected according to the distribution and weathering of the glacial tills,the relationship among the glacial deposits,and the loess or soil developed on the moraines. Electron spin resonance(ESR) dating of the samples was done using the germanium(Ge) centers in the glacial quartz grains,which are sensitive to both sunlight and grinding.The ages of the glacial deposits can be divided into four clusters,i.e.,13.1±0.8-27.0±2.2,36.4±3.3-48.7±5.7,65.6±6.8-86.6±8.9,and 105.6±9.4-178.3±17.8 ka.Six glacial advances in this region have been confirmed,which are equivalent in age to the Little Ice Age(LIA) ,Neoglaciation,marine oxygen isotope stages(MIS) 2,mid-MIS3,MIS4,and MIS6.The largest local last glacial maximum(LGML) occurred during MIS4 rather than the global Last Glacial Maximum(LGMG) of MIS2,and a glacial advance that occurred during mid-MIS3 was also larger than the LGMG.Furthermore,deeply weathered tills below 3500 m a.s.l.on the western slope of Kongur Mountain,when compared with the ages of the oldest glaciation of the Muztag Ata region,likely occurred prior to the penultimate glacial cycle.The glacial landforms prior to the penultimate glacial cycle on the northern slope are not well-preserved due to erosion after deposition. Several glacial deposits are only speculated to be distributed at higher elevations on the southwest side of the Gaizi Checkpoint. The extensive hummocky moraines on the western slope were formed by multiple glacial advances,and the latest glacial advance corresponded to mid-MIS3. 展开更多
关键词 Kongur Mountain glacial geomorphology ESR dating Quaternary glaciation hummocky moraine
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Western Pacific in glacial cycles: Seasonality in marginal seas and variabilities of Warm Pool 被引量:14
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作者 汪品先 《Science China Earth Sciences》 SCIE EI CAS 1998年第1期35-41,共7页
A serics of low-latitude marginal seas, ranging from the southern South China Sea in the north to the Arafura Sea in the south, are located within the Western Pacific Warm Pool. As shown by rnicropaleontological, isot... A serics of low-latitude marginal seas, ranging from the southern South China Sea in the north to the Arafura Sea in the south, are located within the Western Pacific Warm Pool. As shown by rnicropaleontological, isotopical and organic geochemical analyses, the sea surface temperatures in the marginal seas at the last glacial maximum were much cooler than those in the open Western Pacific Ocean. The emergence of extensive shelves of the marginal seas at the glacial low sea-level stand and the decrease of surface temperatures in their deeper water parts resulted in a remarkable reduction of the ability of vapor and heat transport to the atmosphere, causing variabilities to the Warm Pool in the glacial cycles. The intensification of winter monsoon at the glacial stages not only led to a decrease of the surface water temperature and hence to an enhanced seasonality, but also carried moisture from the sea to the tropical islands, giving rise to the downward shift of snowline and mountainous vegetation zones there. It may offer a new alternative in solution of the “Tropical Ocean Paleo-temperature Enigma”. 展开更多
关键词 Western Pacific Warm Pool MARGINAL SEAS glacial cycles PALEOCLIMATE East Asian monsoon.
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PRELIMINARY RESEARCHES ON LICHENOMETRIC CHRONOLOGY OF HOLOCENE GLACIAL FLUCTUATIONS AND ON OTHER TOPICS IN THE HEADWATER OF URUMQI RIVER, TIAN-SHAN MOUNTAINS 被引量:13
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作者 陈吉阳 《Science China Chemistry》 SCIE EI CAS 1989年第12期1487-1500,共14页
This paper introduced briefly the research results on lichenometry of the Holoceneglacial fluctuations in the headwater of the Urumqi River, in the central TianshanMountains and discussed the histories of the Holocene... This paper introduced briefly the research results on lichenometry of the Holoceneglacial fluctuations in the headwater of the Urumqi River, in the central TianshanMountains and discussed the histories of the Holocene glaciers and the climate. It isconsidered that lichenometry is one applicable method for dating the mid- and late-Holocene deposits in the cold and mountainous regions. Rhizocarpon geographicum (L.)DCand Xanthoria elegans (Link.) Th. Fr. could be used for dating the deposits of about 4500and 500 a B.P. respectively. There existed at least four periods of glacial advances whichoccurred before about 5700, 4100, 2800 and 403- 74 a B. P. respectively with the firstperiod the longest. Little Ice Age includes three stages of glacial advances which endedbefore about 403, 208 and 74 a B. P. respectively with the second stage the maximum.During the general Holocene warming processes, there existed at least four cold peri-ods which ended before about 5700, 4100, 2800 and 420- 91 a B.P. respectively, the averageair temperatures of which were about 1.5, 1.25, 0.9 and 0.65℃ higher than the presentone respectively with the warm periods in between. The amplitude of air temperaturechanges is about 2.5℃. 展开更多
关键词 lichenometric CHRONOLOGY HOLOCENE glacial fluctuation HEADWATER of URUMQI RIVER
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Complicated responses of stalagmite δ ^(13)C to climate change during the last glaciation from Hulu Cave, Nanjing,China 被引量:13
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作者 R. L. Edwards 《Science China Earth Sciences》 SCIE EI CAS 2005年第12期2174-2181,共8页
We present a record on carbon stable isotopic composition (δ 13C), covering 75 through 10 thousands years ago (ka B.P.), from Hulu Cave, Nanjing. The overlapping δ 13C pro-files are very similar in pattern and range... We present a record on carbon stable isotopic composition (δ 13C), covering 75 through 10 thousands years ago (ka B.P.), from Hulu Cave, Nanjing. The overlapping δ 13C pro-files are very similar in pattern and range, indicating that they mainly record climatic signal. Dur-ing the last glacial-interglacial transition, the >6‰ change of δ 13C values implies different con-tributions of C3 vs. C4 type plants in soils. On millennial scale, however, the increased calcite δ 13C during the warm Dansgaard-Oeschger (DO) events suggests a decrease of dissolved bio-genic CO2 when water flux rate through soil is large. This correlation between heavier δ 13C and higher precipitation is consistent with our previous report on the samples’ stable oxygen isotope records (Wang et al., 2001). Comparison of coeval δ 13C and δ 18O of stalagmites indicates that kinetic fractionation of carbon isotope is closely related to growth rate of stalagmites. This study also shows that local vegetation changes may lag behind precipitation changes by ~700 years during the deglaciation. 展开更多
关键词 Hulu Cave STALAGMITE δ 13C last glacial period.
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Late Pleistocene glaciation of the Hulifang Massif of Gongwang mountains in Yunnan Province 被引量:13
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作者 ZHANG Wei CUI Zhijiu +2 位作者 FENG Jinliag YI Chaolu YA NG Jianqiang 《Journal of Geographical Sciences》 SCIE CSCD 2005年第4期448-458,共11页
Late Pleistocene glaciation was restricted to only a few high mountains in eastern China. The Gongwang mountains constitute one of the typical places once glaciated. Geomorphic mapping of the area and the TL dating pr... Late Pleistocene glaciation was restricted to only a few high mountains in eastern China. The Gongwang mountains constitute one of the typical places once glaciated. Geomorphic mapping of the area and the TL dating provides evidence for at least four distinct glaciations. YJT-Ⅰ glacial advance occurred about 100 ka BP and two TL absolute ages (101,100 ± 7780 a BP; 104,000± 8300 a BP) indicate this advance happened during the Penultimale Glaciation. The early stage glacial advance (YJT-Ⅱ advance) during the last glaciation occurred about 40,920 ± 3400 a BP. The last glacial maximum advance (YJT-Ⅲ advance) about 18-25 ka BP, which sustained by two TL ages (18,230 ±1420 a BP; 25,420 ± 2110 a BP). The Penultimale and the early stage glaciations were more extensive and the last glacial maximum (LGM) and the late-glacial period (YJT-Ⅳ advance, 10 ka BP) were progressively less extensive. Correlated with the other mountains in eastern China, these glacial advances in the Gongwang mountains just like the advances in the western part such as Diancang mountains, Yulong mountains of Yunnan Province and the glacier series are more complete than the adjacent mid-latitude regions such as Taibai mountain and Taiwan mountains and are roughly representative of climate changes during the last glacial cycle in Yunnan Province. 展开更多
关键词 glacial geomorphology TL dating late Pleistocene last glaciation China
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“Tali Glaciation” on Massif Diancang 被引量:13
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作者 YANG JianQiang1, CUI ZhiJiu2, YI ChaoLu1, SUN JiMin3 & YANG LiRong3 1 Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China 2 College of Environmental Sciences, Peking University, Beijing 100871, China 3 Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 《Science China Earth Sciences》 SCIE EI CAS 2007年第11期1685-1692,共8页
The term of ''Tali Glaciation'' is nominated from Massif Diancang in Yunnan Province. The confusing process of the term''s being put forward is confirmed through literature checking. Based on s... The term of ''Tali Glaciation'' is nominated from Massif Diancang in Yunnan Province. The confusing process of the term''s being put forward is confirmed through literature checking. Based on several times of field trip, the glacial landforms in this region are studied in detail, and the magnitude of the glaciation was determined. According to the numerical ages from TL, AIMS ^(14)C and OSL dating, the earliest glacial advance on Massif Diancang occurred at 30—40 ka BP, followed by the advances at the last stage of the last glaciation, the late glacial and neoglations in turn, until glaciers vanished at 1.2—1.5 ca. a BP in this region. It can be concluded that glaciers were limited above 3600 m a.s.l., and no glaciers existed on the lower part and adjacent mountains since the last glaciation. 展开更多
关键词 MASSIF Diancang Tali Glaciation glacial landform glaciation sequence numerical DATING
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Pollen record of the last 280 ka from deep sea sediments of the northern South China Sea 被引量:15
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作者 孙湘君 罗运利 《Science China Earth Sciences》 SCIE EI CAS 2001年第10期879-888,共10页
Environmental history of the northern continental shelf of the South China Sea during the last 280 ka BP, e.g. Marine Isotope Stages 1–8 (MIS 1–8) was reconstructed based on pollen record from the top 225m of ODP 11... Environmental history of the northern continental shelf of the South China Sea during the last 280 ka BP, e.g. Marine Isotope Stages 1–8 (MIS 1–8) was reconstructed based on pollen record from the top 225m of ODP 1144 Site. During the interglacial periods, pollen assemblages are predominated by pine similar to those of the present day indicating that the environment of the interglacial periods was more or less close to that of today. Nevertheless, those from glacial periods are characterized by a large amount of herbaceous pollen, e.g.Artemisia, Gramineae, Cyperaceae, etc. inferring that grassland covered the merged continental shelf when the sea level lowered and the continental shelf was exposed. The exposed areas of the shelf were insignificant before MIS 5, but enlarged since MIS 4 and reached its maximum during MIS 2 according to ratios of pollen percentages between pine and herbs. The history of different exposure of the shelf can be compared with transgression records of the coastal areas of China and might result from neotectonic movement of Chinese continent. Some changes also took place in the components of grassland growing on the shelf during glaciations. Gramineae is the main element at MIS 8. ThenArtemisia increased upwards the profile and at last became the main component at the Last Glacial Maximum (MIS 2). Such changes in vegetation might be in response to cooler and drier climate. 展开更多
关键词 The South China Sea continental shelf glacial period pollen and spores VEGETATION
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Climatic variations since the Little Ice Age recorded in the Guliya Ice Core 被引量:9
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作者 姚檀栋 焦克勤 +3 位作者 田立德 杨志红 施维林 Lonnie G. Thompson 《Science China Earth Sciences》 SCIE EI CAS 1996年第6期587-596,共10页
The climatic variations since the Little Ice Age recorded in the Guliya Ice Core are discussed based on glacial δ18O and accumulation records in the Guliya Ice Core. Several obvious climate fluctuation events since 1... The climatic variations since the Little Ice Age recorded in the Guliya Ice Core are discussed based on glacial δ18O and accumulation records in the Guliya Ice Core. Several obvious climate fluctuation events since 1570 can be observed according to the records. In the past 400 years, the 17th and 19th centuries are relatively cool periods with less precipitation, and the 18th and 20th centuries are relatively warm periods with high precipitation. The study has also revealed the close relationship between temperature and precipitation on the plateau. Warming corresponds to high precipitation and cooling corresponds to less precipitation, which is related with the influence of monsoon on this region. 展开更多
关键词 Guliya Ice Core δ^(18)O glacial accumulation monsoon.
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Glacial Runoff Likely Reached Peak in the Mountainous Areas of the Shiyang River Basin,China 被引量:13
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作者 ZHANG Shi-qiang GAO Xin Zhang Xiao-wen 《Journal of Mountain Science》 SCIE CSCD 2015年第2期382-395,共14页
Glacier runoff in mountain areas of the Shiyang River Basin(SRB), Qilian Mountain, western China is important for the river and water supply downstream. Small glaciers with area of less than 1km2 are dominant(87%) in ... Glacier runoff in mountain areas of the Shiyang River Basin(SRB), Qilian Mountain, western China is important for the river and water supply downstream. Small glaciers with area of less than 1km2 are dominant(87%) in the SRB. A modified monthly degree-day model was applied to quantify the glacier mass balance, area, and changes in glacier runoff in the SRB during 1961–2050. The comparison between the simulated and observed snow line altitude, annual glacier runoff, and mass balance from1961 to 2008 suggests that the degree-day model may be used to analyze the long-term change of glacier mass balance and runoff in the SRB. The glacier accumulation shows a significant(p<0.01) decreasing trend of-0.830 mm a-1. The mass balance also shows a significant(p<0.01) decreasing trend of-5.521 mm a-1. The glacier total runoff has significantly(p<0.05)increased by 0.079 × 105 m3 from 1961 to 2008. The monthly precipitation and air temperature are projected to significant(p<0.005) increase during2015 to 2050 under three different scenarios. The ablation is projected to significant(p<0.001) increase,while the accumulation has no significant(p=0.05)trend. The mass balance is projected to decrease, theglacier area is projected to decrease, and the glacier runoff depth is projected to increase. However, the glacier total runoff is projected to decrease. These results indicate that the glacier total runoff over glacier areas observed in 1970 reached its peak in the 2000 s. This will exacerbate the contradiction between water supply and downstream water demands in the SRB. 展开更多
关键词 Climate change Mass balance glacial runoff Glacier area Shiyang River Basin
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High-Resolution Records of the Holocene Paleoenvironmental Variation Reflected by Carbonate and Its Isotopic Compositions in Bosten Lake and Response to Glacial Activities 被引量:10
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作者 ZHANG Chengjun ZHENG Mianping +5 位作者 Alexander PROKOPENKO Steffen MISCHKE GOU Xiaohui YANG Qili ZHANG Wanyi FENG Zhaodong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第6期1101-1115,共15页
The Early Holocene paleoclimate in Bosten Lake on the northern margin of the Tarim Basin, southern Xinjiang, is reconstructed through an analysis of a 953 cm long core (BSTC2000) taken from Bosten Lake. Multiple pro... The Early Holocene paleoclimate in Bosten Lake on the northern margin of the Tarim Basin, southern Xinjiang, is reconstructed through an analysis of a 953 cm long core (BSTC2000) taken from Bosten Lake. Multiple proxies of this core, including the mineral components of carbonate, carbonate content, stable isotopic compositions of carbonate, Ca/Sr, TOC and C/N and C/S of organic matter, are used to reconstruct the climatic change since 8500 a B.P. The chronology model is made by nine AMS 14C ages of leaves, seeds and organic matter contained in two parallel cores. The climate was cold and wet during 8500 to 8100 a B.P. Temperature increased from 8100 to 6400 a B.P., the climate was warm and humid, and the lake expanded. The lake level was highest during this stage. Then from 6400 to 5100 a B.P., the climate became cold and the lake level decreased slightly. During the late mid-Holocene, the climate was hot and dry from 5100 to 3100 a B.P., but there was a short cold period during 4400 to 3800 a B.P. At this temporal interval, a mass of ice and snow melting water supplied the lake at the early time and made the lake level rise. The second highest lake level stage occurred during 5200 to 3800 a B.P. The climate was cool and wet during 3100 to 2200 a B.P., when the lake expanded with decreasing evaporation. The lake had the last short-term high level during 3100 to 2800 a B.P. After this short high lake level period, the lake shrank because of the long-term lower temperature and reduced water supply. From 2200 to 1200 a B.P., the climate was hot and dry, and the lake shrank greatly. Although the temperature decreased somewhat from 1200 a B.P. to the present, the climate was warm and dry. The lake level began to rise a little again, but it did not reach the river bed altitude of the Konqi River, an outflow river of the Bosten Lake. 展开更多
关键词 CARBONATE isotopic composition glacial activity paleoenvironmental variation Bosten Lake
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Definition and classification system of glacial lake for inventory and hazards study 被引量:10
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作者 姚晓军 刘时银 +2 位作者 韩磊 孙美平 赵琳林 《Journal of Geographical Sciences》 SCIE CSCD 2018年第2期193-205,共13页
Glacial lakes are not only the important refresh water resources in alpine region, but also act as a trigger of many glacial hazards such as glacial lake outburst flood (GLOF) and debris flow. Therefore, glacial lak... Glacial lakes are not only the important refresh water resources in alpine region, but also act as a trigger of many glacial hazards such as glacial lake outburst flood (GLOF) and debris flow. Therefore, glacial lakes play an important role on the cryosphere, climate change and alpine hazards. In this paper, the issues of glacial lake were systematically discussed, then from the view of glacial lake inventory and glacial lake hazards study, the glacial lake was defined as natural water mainly supplied by modern glacial meltwater or formed in glacier moraine's depression. Furthermore, a complete classification system of glacial lake was proposed based on its formation mechanism, topographic feature and geographical position. Glacial lakes were classified as 6 classes and 8 subclasses, i.e., glacial erosion lake (including cirque lake, gla- cial valley lake and other glacial erosion lake), moraine-dammed lake (including end mo- raine-dammed lake, lateral moraine-dammed lake and moraine thaw lake), ice-blocked lake (including advancing glacier-blocked lake and other glacier-blocked lake), supraglacial lake, subglacial lake and other glacial lake. Meanwhile, some corresponding features exhibiting on remote sensing image and quantitative indices for identifying different glacial lake types were proposed in order to build a universal and operational classification system of glacial lake. 展开更多
关键词 glacial lake GLACIER DEFINITION CLASSIFICATION INVENTORY HAZARD
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Glacial advances and ESR chronology of the Pochengzi Glaciation,Tianshan Mountains,China 被引量:9
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作者 ZHAO JingDong LIU ShiYin +2 位作者 WANG Jie SONG YouGui DU JianKuo 《Science China Earth Sciences》 SCIE EI CAS 2010年第3期403-410,共8页
The Pochengzi Glaciation is a typical glaciation in Quaternary in the Tianshan Mountains. The glacial landforms comprise several integrated end moraines, like a fan spreading from the north to the south at the mouth o... The Pochengzi Glaciation is a typical glaciation in Quaternary in the Tianshan Mountains. The glacial landforms comprise several integrated end moraines, like a fan spreading from the north to the south at the mouth of the Muzhaerte River valley and on the piedmont on the southeastern slope of the Tumur Peak, the largest center of modern glaciation in the Tianshan Mountains. The landforms recorded a complex history of the ancient glacier change and contained considerable information of the glacial landscape evolution, and dating these landforms helps us understand the temporal and spatial shifts of the past cryosphere in this valley and reconstruct the paleoenvironment in this region. Electron spin resonance (ESR) dating of the glacial tills in the upper stratum from a well-exposed section, end moraines, and associated outwashes was carried out using Ge centers in quartz grains, which are sensitive to the sunlight and grinding. The results could be divided into three clusters, 13.6–25.3, 39.5–40.4 and 64.2–71.7 ka. Based on the principle of geomorphology and stratigraphy and the available paleoen- vironmental data from northwestern China, the end moraines were determined to deposit in the Last Glaciation. The landforms and the three clusters of ages demonstrate that at least three large glacial advances occurred during the Pochengzi Glaciation, which are corresponding to marine oxygen isotope stage 4 (MIS4), MIS3b and MIS2. The landforms also indicate that the gla- ciers were compound valley glacier in MIS2 and MIS3b and piedmont glacier in MIS4, and the ancient Muzhaerte glacier were 94, 95 and 99 km at their maximum extensions in these three glacial advances. 展开更多
关键词 ESR dating glacial advance Pochengzi GLACIATION TIANSHAN Mountains
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