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The Maximum Ice Age Glaciation between the Karakorum Main Ridge (K_2) and the Tarim Basin and its Influence on Global Energy Balance 被引量:1
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作者 Matthias Kuhle 《Journal of Mountain Science》 SCIE CSCD 2005年第1期5-22,共18页
A modern research approach and working techniques in hitherto unexamined areas, produced the following results: 1). The tongues of deca- kilometre long Karakorum glaciers belong to temperate ice-streams with an an... A modern research approach and working techniques in hitherto unexamined areas, produced the following results: 1). The tongues of deca- kilometre long Karakorum glaciers belong to temperate ice-streams with an annual meltwater output. The short Aghil glaciers on the contrary are continental, arid and cold. 2). The present-day oscillations of the Karakorum glaciers are related to their own mass, and are contrary to and independent of the actual climate. Only the short glaciers, with steep tongue fronts, show a present-day positive balance. 3). C- dated Late Glacial moraines indicate14 a 400~800 m thick valley glacier at the former confluence point of the K2-, Sarpo Laggo- and Skamri glaciers. 4). From the evidence of transfluence passes with roches moutonnées, striae and the limits of glacial polishing, as well as moraines and erratics, a High Glacial at least 1200 m thick ice-stream network between the Karakorums and the Kuen Lun north slopes was reconstructed. The Shaksgam and Yarkand valleys were occupied by glaciers coming from west Tibet. The lowest-lying moraines are to be found in the foreland down to 2000 m, indicating a depression of the High Glacial (LGM) snowline (ELA) by 1300 m. 5). The approximately 10,000 measurements of the radiation balance at up to heights of 5500 m on K2 indicate that with incoming energy near the solar constant the reflection from snow- covered ice is up to 70% greater than from rock and rock waste surfaces. 6).These results confirm for the very dry western margins of Tibet an almost complete ice sheet cover in an area with subtropical energy balance, conforming with the Ice Age hypothesis of the author which is based upon the presence of a 2.4 million km2 Tibetan inland ice sheet. This inland ice developed for the first time when Tibet was uplifted over the snowline during the early Pleistocene. As the measured subtropical radiation balance shows, it was able to trigger the Quaternary Ice Ages. 展开更多
关键词 KARAKORUM Tibet ice age glaciation PALEOCLIMATE ice age theory high mountain geomorphology
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Interannual Climate Variability Change during the Medieval Climate Anomaly and Little Ice Age in PMIP3 Last Millennium Simulations 被引量:4
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作者 Kaiqing YANG Dabang JIANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第4期497-508,共12页
In this study, we analyzed numerical experiments undertaken by 10 climate models participating in PMIP3(Paleoclimate Modelling Intercomparison Project Phase 3) to examine the changes in interannual temperature varia... In this study, we analyzed numerical experiments undertaken by 10 climate models participating in PMIP3(Paleoclimate Modelling Intercomparison Project Phase 3) to examine the changes in interannual temperature variability and coefficient of variation(CV) of interannual precipitation in the warm period of the Medieval Climate Anomaly(MCA) and the cold period of the Little Ice Age(LIA). With respect to the past millennium period, the MCA temperature variability decreases by 2.0% on average over the globe, and most of the decreases occur in low latitudes. In the LIA, temperature variability increases by a global average of 0.6%, which occurs primarily in the high latitudes of Eurasia and the western Pacific. For the CV of interannual precipitation, regional-scale changes are more significant than changes at the global scale, with a pattern of increased(decreased) CV in the midlatitudes of Eurasia and the northwestern Pacific in the MCA(LIA). The CV change ranges from-7.0% to 4.3%(from -6.3% to 5.4%), with a global average of -0.5%(-0.07%) in the MCA(LIA).Also, the variability changes are considerably larger in December–January–February with respect to both temperature and precipitation. 展开更多
关键词 interannual variability last millennium Medieval Climate Anomaly Little ice age
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The Approaching New Grand Solar Minimum and Little Ice Age Climate Conditions 被引量:2
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作者 Nils-Axel Morner 《Natural Science》 2015年第11期510-518,共9页
By about 2030-2040, the Sun will experience a new grand solar minimum. This is evident from multiple studies of quite different characteristics: the phasing of sunspot cycles, the cyclic observations of North Atlantic... By about 2030-2040, the Sun will experience a new grand solar minimum. This is evident from multiple studies of quite different characteristics: the phasing of sunspot cycles, the cyclic observations of North Atlantic behaviour over the past millennium, the cyclic pattern of cosmogenic radionuclides in natural terrestrial archives, the motions of the Sun with respect to the centre of mass, the planetary spin-orbit coupling, the planetary conjunction history and the general planetary-solar-terrestrial interaction. During the previous grand solar minima—i.e. the Sporer Minimum (ca 1440-1460), the Maunder Minimum (ca 1687-1703) and the Dalton Minimum (ca 1809-1821)—the climatic conditions deteriorated into Little Ice Age periods. 展开更多
关键词 Solar Variability Grand Solar Minima Little ice ages The 2030-2040 Solar Minimum
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THE SAND WEDGE AND MIRABILITE OFTHE LAST ICE AGE AND THEIR PALEOCLIMATICSIGNIFICANCE IN HEXI CORRIDOR
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作者 HU Gang, WANG Nai-ang (School of Resources and Environment, Lanzhou University, Lanzhou 730000, P. R. China Cold and Arid Regrons Environment and Engineering Research Institute, the Chinese Academy of Scienes, Lanzhou 730000, P. R. China) 《Chinese Geographical Science》 SCIE CSCD 2001年第1期80-86,共7页
The sand wedges in Hexi Corridor occur in the alluvial gravel stratum of bajada and high terraces. The 14C ages of eolian sand in sand wedges prove that they formed during the Last Ice Age, with the mean annual air te... The sand wedges in Hexi Corridor occur in the alluvial gravel stratum of bajada and high terraces. The 14C ages of eolian sand in sand wedges prove that they formed during the Last Ice Age, with the mean annual air temperature about ? 5.6°C. The common 14C and AMS 14C dating ages of terrestrial branch relicts in Huahai clay-mirabilite interlayer are (11 600 ± 280) a B. P. and (1118 ± 54) a B. P. respectively, proving that the mirabilite formed at the cold episode of the Last Glacial Maximum(LGM) and Younger Dryers(YD) in Huahai Lake. It is pointed out that the mean annual air temperature in Hexi Corridor during LGM was about ?3°C – ?7°C, 11°C – 15°C lower than that of present, and that during YD was about 0°C – 2°C, 6°C – 8°C lower than at present. This decreasing temperature values are generally coincident with those inferred by pollen, sand wedge and ice core in the northern China, and also with the research on temperature-falling amplitude of middle and high latitude on the Northern Hemisphere recently. 展开更多
关键词 sand wedge Last ice age Hexi Corridor PALEOCLIMATE
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Climate Disasters and Climate Variation of Little Ice Age in East Asia
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作者 Yoshio Tagami 《Cultural and Religious Studies》 2017年第5期243-247,共5页
In this paper, climate variation is reconstructed on the basis of the chronicles of weather disasters in Japan and China. There remain many rainstorm records in southern coast of Japan, and south-eastern coast of Chin... In this paper, climate variation is reconstructed on the basis of the chronicles of weather disasters in Japan and China. There remain many rainstorm records in southern coast of Japan, and south-eastern coast of China. Both in Japan and China, many rainstorm disasters appeared in summer. But, they usually appeared one or two months later in Japan. The period of frequent windstorm damage occurrence in Little Ice Age differs among Japan and China, and it was caused by the change of atmospheric circulation. Cool summer period appeared around 1705, 1740, 1765, 1785, 1830, and 1845. It was generally cool before 1855, but it became warm after 1855. It corresponds with the sudden retreat of glaciers of European Alps. 展开更多
关键词 climate variation Little ice age East Asia TYPHOON GUFU
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Weak chemical weathering during the Little Ice Age recorded by lake sediments 被引量:10
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作者 金章东 王苏民 +3 位作者 沈吉 张恩楼 季峻峰 李福春 《Science China Earth Sciences》 SCIE EI CAS 2001年第7期652-658,共7页
Low magnetic susceptibility, low Sr content and hence high Rb/Sr ratio in the lake sediment sequence indicate a weak chemical weathering process under arid and cold climate of the Little Ice Age in a single closed lak... Low magnetic susceptibility, low Sr content and hence high Rb/Sr ratio in the lake sediment sequence indicate a weak chemical weathering process under arid and cold climate of the Little Ice Age in a single closed lake watershed. According to different geochemical behavior between rubidium and strontium in earth surface processes, variation of Rb/Sr ratios in the lake sediment sequence can be used as an effective geochemical proxy with definite climatic significance of chemical weathering in watershed. Unlike chemical weathering process in tropic zone and modern temperate-humid climate, concordant changes in both Sr content and magnetic susceptibility with δ18O values of Dunde ice core suggest that the weak chemical weathering was controlled by air temperature during the Little Ice Age maximum. After the Little Ice Age, chemical weathering intensity was controlled also gradually by precipitation with increasing in temperature. 展开更多
关键词 closed lake Rb/Sr ratio chemical weathering the Little ice age
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Tree ring-dated fluctuation history of Midui glacier since the Little Ice Age in the southeastern Tibetan Plateau 被引量:5
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作者 XU Peng ZHU HaiFeng +1 位作者 SHAO XueMei YIN ZhiYong 《Science China Earth Sciences》 SCIE EI CAS 2012年第4期521-529,共9页
Fluctuation history of Midui glacier in the southeastern Tibet since the Little Ice Age(LIA) was reconstructed by the dating of lateral and terminal moraines using tree rings.Four conversions of glacier advance/stabil... Fluctuation history of Midui glacier in the southeastern Tibet since the Little Ice Age(LIA) was reconstructed by the dating of lateral and terminal moraines using tree rings.Four conversions of glacier advance/stabilization to retreat were identified at around 1767,1875,1924 and 1964.The glacier reached its LIA maximum position at 1767.The fluctuations are consistent with those of other glaciers from the Tibetan Plateau,the Rockies and the Alps,suggesting high spatial coherency of glacier fluctuations in the Northern Hemisphere.Comparison with the summer temperature reconstruction in the southeastern Tibetan Plateau indicated that the Midui glacier fluctuation may be related to temperature variation on the centennial timescale.On the decadal scale,the fluctuation could correspond to cold/warm variation with an 8-year lag on average. 展开更多
关键词 Tibetan Plateau glacier fluctuation tree ring Little ice age climate change moraine dating
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THE NUMERICAL SIMULATION OF THE ICE AGE CLIMATE
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作者 王会军 曾庆存 《Acta meteorologica Sinica》 SCIE 1993年第4期423-430,共8页
Using the lAP two-level general circulation model,the ice age July climate was simulated through the surface con- ditions of 18 000 years before present assembled by the CLIMAP Project.Comparing with the present July ... Using the lAP two-level general circulation model,the ice age July climate was simulated through the surface con- ditions of 18 000 years before present assembled by the CLIMAP Project.Comparing with the present July simulation results,the ice age atmosphere is found to have a substantially lower temperature,precipitation,and cloudiness,higher sea-level pressure,especially in the high latitude land region of the Northern Hemisphere and Antarctica.When the CO2 content is set as the modern value the climatic response is very small,which shows that the problems of CO2 sen- sitivity should be studied by means of coupled models.It is also pointed out that there are some common characteristics between CO2-induced climatic changes and the ice age surface condition-induced climatic changes,which may give us some insight into how climate responds to external forcings. 展开更多
关键词 numerical simulation ice age climate CO_2 content
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A New Ice Age? None Soon,Snow 2 Miles Deep Implies
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作者 Andrew C.Revkin 李杨 《当代外语研究》 2004年第10期10-11,共2页
冰川学专家认为,全球气候在漫长的地质年代中曾有数次冷暖变化,冰川作用随之重复发生。气候寒冷时,降雪量增加,发育大规模的冰川,巨大的冰盖掩盖地球,称为冰川期(ice age)。地球已经历了四次大冰川期,第五纪冰川期是否即将来临?科学家... 冰川学专家认为,全球气候在漫长的地质年代中曾有数次冷暖变化,冰川作用随之重复发生。气候寒冷时,降雪量增加,发育大规模的冰川,巨大的冰盖掩盖地球,称为冰川期(ice age)。地球已经历了四次大冰川期,第五纪冰川期是否即将来临?科学家对此进行了研究。 展开更多
关键词 A New ice age None Soon Snow 2 Miles Deep Implies
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Habitable Land Will Soon Become the World’s Scarcest Resource: Why Appalachia Should Choose Climate Change Havens over Millionaire Estates and Golf Courses
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作者 Elizabeth C. Hirschman Devonte Booth +5 位作者 Tzu-Wei Huang Kamryn Livingston Kobe McReynolds Rachel Six Logan Smith Olivia Toomer 《Journal of Environmental Protection》 2024年第6期716-730,共15页
This research advocates for the construction of Climate Change Haven Communities across the Appalachian Region. The proposed development plan can be extended to the northern tier states across the US and also to the n... This research advocates for the construction of Climate Change Haven Communities across the Appalachian Region. The proposed development plan can be extended to the northern tier states across the US and also to the northern and mountainous regions of Europe and Asia. We present an analogy to the earlier climate change period of the Last Glacial Maximum/“Ice Age” in which these same northern regions of the planet were covered in ice sheets making them uninhabitable for most humans and many plant and animal species. In some significant ways, the Ice Age scenario can be a reverse-model for our current climate crisis. We also advocate strongly for the prevention of upscale real estate development projects in these same regions of the globe, as these will foreclose the possibility of safely sheltering the millions of persons who will be displaced by climate change over the next 5 to 10 years. 展开更多
关键词 Climate Change APPALACHIA Habitable Land Climate Change Haven Communities Two-Caste Economic System Migration ice age Analogies
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The Glacial(MIS 3-2)Outlet Glacier of the Marsyandi Nadi-icestream-network with its Ngadi Khola Tributary Glacier(Manaslu-and Lamjung Himalaya):The Reconstructed Lowering of the Marsyandi Nadi Ice Stream Tongue down in to the Southern Himalaya Foreland 被引量:2
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作者 Matthias KUHLE 《Journal of Mountain Science》 SCIE CSCD 2014年第1期236-287,共52页
For the reconstruction of past climate variations,investigations on the history of glaciers are necessary.In the Himalaya,investigations like these have a rather short tradition in comparison with other mountains on e... For the reconstruction of past climate variations,investigations on the history of glaciers are necessary.In the Himalaya,investigations like these have a rather short tradition in comparison with other mountains on earth.At the same time,this area on the southern margin of Tibet is of special interest because of the question as to the monsoon-influence that is connected with the climate-development.Anyhow,the climate of High Asia is of global importance.Here for the further and regionally intensifying answer to this question,a glacial glacier reconstruction is submitted from the CentralHimalaya,more exactly from the Manaslu-massif.Going on down-valley from the glacial-historical investigations of 1977 in the upper Marsyandi Khola(Nadi) and the partly already published results of field campaigns in the middle Marsyandi Khola and the Damodar- and Manaslu Himal in the years 1995,2000,2004 and 2007,new geomorphological and geological field- and laboratory data are introduced here from the Ngadi(Nadi) Khola and the lower Marsyandi Nadi from the inflow of the Ngadi(Nadi) Khola down to the southern mountain foreland.There has existed a connected ice-stream-network drained down to the south by a 2,100-2,200 m thick and 120 km long Marsyandi Nadi main valley glacier.At a height of the valley bottom of c.1,000 m a.s.l.the Ngadi Khola glacier joined the still c.1,300 m thick Marsyandi parent glacier from the Himalchuli-massif(Nadi(Ngadi) Chuli) – the south spur of the Manaslu Himal.From here the united glacier tongue flowed down about a further 44 km to the south up to c.400 m a.s.l.(27°57'38 "N/84°24'56" E) into the Himalaya fore-chains and thus reached one of or the lowest past ice margin position of the Himalayas.The glacial(LGP(Last glacial period),LGM(Last glacial maximum) Würm,Stage 0,MIS 3-2) climatic snowline(ELA = equilibrium line altitude) has run at 3,900 to 4,000 m a.s.l.and thus c.1,500 altitude meters below the current ELA(Stage XII) at 5,400-5,500 m a.s.l.The reconstructed,maximum lowering of the climatic snowline(ΔELA = depression of the equilibrium line altitude) about 1,500 m corresponds at a gradient of 0.6°C per 100 altitude meters to a High Glacial decrease in temperature of 9°C(0.6 × 15 = 9).At that time the Tibetan inland ice has caused a stable cold high,so that no summer monsoon can have existed there.Accordingly,during the LGP the precipitation was reduced,so that the cooling must have come to more than only 9°C. 展开更多
关键词 ice age GLACIATION HIMALAYA Manaslu Ngadi Khola icestream network Last Glacial period
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Multi-scale analysis on last millennium climate variations in Greenland by its ice core oxygen isotope
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作者 MingTong Yu ZhenShan Lin +1 位作者 JianLi Du ZhenZhen Zhang 《Research in Cold and Arid Regions》 2010年第2期123-128,共6页
The empirical mode decomposition method is used for analyzing the paleoclimate proxy δ18O from Greenland GISP2 ice core.The results show that millennium climate change trends in Greenland record the Medieval Warm Per... The empirical mode decomposition method is used for analyzing the paleoclimate proxy δ18O from Greenland GISP2 ice core.The results show that millennium climate change trends in Greenland record the Medieval Warm Period (MWP) from 860AD-1350AD lasting for about 490 years,and the Little Ice Age (LIA) from 1350AD-1920AD lasting about 570 years.During these events,sub cooling-warming variations occurred.Its multi-scale oscillations changed with quasi-period of 3-year,6.5-year,12-year,24-year,49-year,96-year,213-year and 468-year,and are not only affected by ENSO but also by solar activity.The oscillation of intrinsic mode function IMF7,IMF8 and their tendency obviously appear in 1350AD which is considered as the key stage of transformation between MWP and LIA.The results give more detailed changes and their stages of millennium climate change in high latitude areas of the Northern Hemisphere. 展开更多
关键词 empirical mode decomposition medieval warm period and little ice age quasi-period of millennium climate oscillation
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Aeolian activity in the southern Gurbantunggut Desert of China during the last 900 years 被引量:1
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作者 LI Wen MU Guijin +2 位作者 YE Changsheng XU Lishuai LI Gen 《Journal of Arid Land》 SCIE CSCD 2023年第6期649-666,共18页
The mineral dust emitted from Central Asia has a significant influence on the global climate system.However,the history and mechanisms of aeolian activity in Central Asia remain unclear,due to the lack of well-dated r... The mineral dust emitted from Central Asia has a significant influence on the global climate system.However,the history and mechanisms of aeolian activity in Central Asia remain unclear,due to the lack of well-dated records of aeolian activity and the intense wind erosion in some of the dust source areas(e.g.,deserts).Here,we present the records of aeolian activity from a sedimentary sequence in the southern Gurbantunggut Desert of China using grain size analysis and optically stimulated luminescence(OSL)dating,based on field sampling in 2019.Specifically,we used eight OSL dates to construct chronological frameworks and applied the end-member(EM)analysis for the grain size data to extract the information of aeolian activity in the southern Gurbantunggut Desert during the last 900 a.The results show that the grain size dataset can be subdivided into three EMs(EM1,EM2,and EM3).The primary modal sizes of these EMs(EM1,EM2,and EM3)are 126.00,178.00,and 283.00μm,respectively.EM1 represents a mixture of the suspension components and saltation dust,while EM2 and EM3 show saltation dust transported over a shorter distance via strengthened near-surface winds,which can be used to trace aeolian activity.Combined with the OSL chronology,our results demonstrate that during the last 900 a,more intensive and frequent aeolian activity occurred during 450-100 a BP(Before Present)(i.e.,the Little Ice Age(LIA)),which was reflected by a higher proportion of the coarse-grained components(EM2+EM3).Aeolian activity decreased during 900-450 a BP(i.e.,the Medieval Warm Period(MWP))and 100 a BP-present(i.e.,the Current Warm Period(CWP)).Intensified aeolian activity was associated with the strengthening of the Siberian High and cooling events at high northern latitudes.We propose that the Siberian High,under the influence of temperature changes at high northern latitudes,controlled the frequency and intensity of aeolian activity in Central Asia.Cooling at high northern latitudes would have significantly enhanced the Siberian High,causing its position to shift southward.Subsequently,the incursion of cold air masses from high northern latitudes resulted in stronger wind regimes and increased dust emissions from the southern Gurbantunggut Desert.It is possible that aeolian activity may be weakened in Central Asia under future global warming scenarios,but the impact of human activities on this region must also be considered. 展开更多
关键词 aeolian activity grain size wind regime Little ice age Siberian High climatic drying Central Asia
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Unmixing detrital zircon U-Pb ages reveals tectonic and climatic depositional influences on the Carboniferous Ansilta Formation,Calingasta-Uspallata Basin,Western Argentina
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作者 J.R.Malone J.E.Malone +3 位作者 J.L.Isbell D.H.Malone J.P.Craddock K.N.Pauls 《Geoscience Frontiers》 SCIE CAS 2024年第4期61-77,共17页
The Late Paleozoic Ice Age(LPIA)was a principal control of sedimentation across Gondwana from the late Devonian through early Permian.We assess the hypothesis that glacial to interglacial transitions in western Argent... The Late Paleozoic Ice Age(LPIA)was a principal control of sedimentation across Gondwana from the late Devonian through early Permian.We assess the hypothesis that glacial to interglacial transitions in western Argentina were the primary control influencing sediment routing patterns among the various Carboniferous-Permian basins in western Argentina.The Carboniferous Ansilta Formation consists of glaciomarine,nearshore,and fluvial systems deposited during the LPIA along the eastern margin of the Calingasta-Uspallata Basin in Argentina.The lower,glacially influenced succession of the Ansilta Formation records at least five glacial advances;the upper succession of consists of progradational shallow marine,deltaic,and fluvial strata.We combine 1225 new U-Pb zircon ages from six samples of the Carboniferous Ansilta Formation in the Calingasta-Uspallata Basin with 5864 U-Pb ages from 147 pub-lished samples in the detrital Pymix forward mixture model to characterize provenance shifts.For the glacially influenced lower Ansilta Formation,sediment was derived locally from the Protoprecordillera,which was a prominent highland with alpine glaciers flowing west and east into the Calingasta-Uspallata and Paganzo basins,respectively.Thus,there was little or no connection between these two basins during Serpukhovian-Bashkirian glaciation.The fluvial/deltaic upper Ansilta had distal sediment sources in the Sierras Pampeanas.Furthermore,our results support the collapse of the Protoprecordillera topographic barrier,enabling drainage patterns connecting the Paganzo and Calingasta-Uspallata basins by late Pennsylvanian-early Permian time. 展开更多
关键词 Late Paleozoic ice age Argentina Calingasta-Uspallata Basin Ansilta Formation Detrital zircon provenance
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Evolution of permafrost in Northeast Chinasince the Late Pleistocene 被引量:5
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作者 HuiJun Jin XiaoLi Chang +6 位作者 DongLiang Luo RuiXia He LanZhi Lu SiZhong Yang DongXin Guo XueMei Chen Stuart A.Harris 《Research in Cold and Arid Regions》 CSCD 2016年第4期269-296,共28页
In Northeast China, permafrost advanced and retreated several times under the influences of fluctuating paleo-climatesand paleo-environments since the Late Pleistocene. During the last 60 years, many new data were obt... In Northeast China, permafrost advanced and retreated several times under the influences of fluctuating paleo-climatesand paleo-environments since the Late Pleistocene. During the last 60 years, many new data were obtained and studies wereconducted on the evolution of permafrost in Northeast China, but so far no systematic summary and review have been made.Based on sedimentary sequences, remains of past permafrost, paleo-flora and -fauna records, and dating data, permafrostevolution since the Late Pleistocene has been analyzed and reconstructed in this paper. Paleo-temperatures reconstructedfrom the remains of past permafrost and those from paleo-flora and -fauna are compared, and thus the southern limitof permafrost (SLP) in each climate period is inferred by the relationship of the permafrost distribution and the meanannual air/ground temperatures (MAAT/MAGT). Thus, the evolutionary history of permafrost is here divided into fivestages: (1) the Late Pleistocene (Last Glaciation, or LG) (65 to 10–8.5 ka), the Last Glaciation Maximum (LGM, 21–13 ka)in particular, the coldest period in the latest history with a cooling of about 6~10 °C, characterized by extensive occurrencesof glaciation, flourishing Mammathas-Coelodonta Faunal Complex (MCFC), widespread aeolian deposits, and significantsea level lowering, and permafrost greatly expanded southwards almost to the coastal plains (37°N–41°N); (2) the HoloceneMegathermal Period (HMP, 8.5–7.0 to 4.0–3.0 ka), 3~5 °C warmer than today, permafrost retreated to about 52°N; (3) theLate Holocene Cold Period (Neoglaciation) (4.0–3.0 to 1.0–0.5 ka), a cooling of 1~3 °C, some earlier thawed permafrost wasrefrozen or attached, and the SLP invaded southwards to 46°N; (4) the Little Ice Age (LIA, 500 to 100–150 a), the latestcold period with significant permafrost expansion; and (5) climate warming since the last century, during which NortheastChina has undergone extensive permafrost degradation. The frequent and substantial expansions and retreats of permafrosthave greatly impacted cold-region environments in Northeast China. North of the SLP during the HMP, or in the presentcontinuous permafrost zone, the existing permafrost was largely formed during the LG and was later overlapped by thepermafrost formed in the Neoglaciation. To the south, it was formed in the Neoglaciation. However, many aspects ofpermafrost evolution still await further investigations, such as data integration, numerical reconstruction, and merging ofChinese permafrost history with those of bordering regions as well as collaboration with related disciplines. Of these, studies on the evolution and degradation of permafrost during the past 150 years and its hydrological, ecological, and environmentalimpacts should be prioritized. 展开更多
关键词 Last Glaciation (LG) Holocene Megathermal Period (HMP) Neoglaciation Little ice age (LIA) NortheastChina permafrost evolution
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Glacial-Interglacial Atmospheric CO_2 Change——The Glacial Burial Hypothesis 被引量:2
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作者 Ning ZENG Department of Meteorology and Earth System Science Interdisciplinary Center, University of Maryland, USA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2003年第5期677-693,共17页
Organic carbon buried under the great ice sheets of the Northern Hemisphere is suggested to be the missing link in the atmospheric CO<SUB>2</SUB> change over the glacial-interglacial cycles. At glaciation,... Organic carbon buried under the great ice sheets of the Northern Hemisphere is suggested to be the missing link in the atmospheric CO<SUB>2</SUB> change over the glacial-interglacial cycles. At glaciation, the advancement of continental ice sheets buries vegetation and soil carbon accumulated during warmer periods. At deglaciation, this burial carbon is released back into the atmosphere. In a simulation over two glacial-interglacial cycles using a synchronously coupled atmosphere-land-ocean carbon model forced by reconstructed climate change, it is found that there is a 547-Gt terrestrial carbon release from glacial maximum to interglacial, resulting in a 60-Gt (about 30-ppmv) increase in the atmospheric CO<SUB>2</SUB>, with the remainder absorbed by the ocean in a scenario in which ocean acts as a passive buffer. This is in contrast to previous estimates of a land uptake at deglaciation. This carbon source originates from glacial burial, continental shelf, and other land areas in response to changes in ice cover, sea level, and climate. The input of light isotope enriched terrestrial carbon causes atmospheric &#948;<SUP>13</SUP>C to drop by about 0.3‰ at deglaciation, followed by a rapid rise towards a high interglacial value in response to oceanic warming and regrowth on land. Together with other ocean based mechanisms such as change in ocean temperature, the glacial burial hypothesis may offer a full explanation of the observed 80–100-ppmv atmospheric CO<SUB>2</SUB> change. 展开更多
关键词 atmospheric CO2 ice age glacial burial hypothesis CLIMATE
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Glacier variations and rising temperature in the Mt.Kenya since the Last Glacial Maximum 被引量:1
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作者 CHEN An-an WANG Ning-lian +2 位作者 GUO Zhong-ming WU Yu-wei WU Hong-bo 《Journal of Mountain Science》 SCIE CSCD 2018年第6期1268-1282,共15页
High-resolution imagery can be used to reconstruct former glacier boundaries through the identification of glacial erosional and sedimentary geomorphology. We employed moraine mapping and the accumulation–area ratio ... High-resolution imagery can be used to reconstruct former glacier boundaries through the identification of glacial erosional and sedimentary geomorphology. We employed moraine mapping and the accumulation–area ratio method(AAR), in conjunction with Landsat, Google Earth, and SRTM imagery, to reconstruct glacier boundaries and equilibrium-line altitudes(ELAs) for Mt. Kenya in the Last Glacial Maximum(LGM), the Little Ice Age(LIA), and at present. Our results show that the areas of Lewis Glacier and the Tyndall-I glacier system were 0.678 km^2 and 0.390 km^2, respectively, during the maximum of LIA. Those mean that the both glaciers have shrunken by 87.0% and 88.7%, respectively since the LIA. Area change ratios for each glacier were significantly larger in the period of 2000 through 2015 than the former periods, indicating that glacier recession has accelerated. Continuous ice loss in this region has been driven by rising temperature and fluctuating precipitation. Linear regression data for Lewis glacier show that mass balance sensitivity to dry season temperature was –315 mm w.e./℃, whereas the sensitivity to dry season precipitation was 5.2 mm w.e./mm. Our data also show that the ELA on the western slope of Mt. Kenya rose by 716-816 m from the LGM to the modern era, corresponding to that temperature rose by 5.2℃-6.5℃. 展开更多
关键词 Remote sensing Last Glacial Maximum Little ice age Glacier area Equilibrium-linealtitudes Mt. Kenya
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Coastal environment of the past millennium recorded by a coastal dune in Fujian,China 被引量:3
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作者 JIN Jianhui LI Zhizhong +3 位作者 JIANG Feng deng tao HU Fan'gen LING Zhiyong 《Journal of Arid Land》 SCIE CSCD 2016年第5期707-721,共15页
Coastal dune is a common aeolian geomorphology in a sandy coast,which records the evolution process of the aeolian landscape system and reflects the complex interaction among land surface,atmosphere and ocean.Coast is... Coastal dune is a common aeolian geomorphology in a sandy coast,which records the evolution process of the aeolian landscape system and reflects the complex interaction among land surface,atmosphere and ocean.Coast is a sensitive area to global climate change.Restricted by chronology,most previous researches in China focused only on the cause of formation of coastal dunes.In recent years,the development of optically stimulated luminescence (OSL) dating provides a good method and acts as a carrier for coastal dunes to paleoclimate and paleoenvironmental studies.In this study,we selected an aeolian dune at the Anshan archaeological site,Fujian,China as the research object based on field observations.For determining their sedimentary stages and the primary influencing factors,we used the OSL dating method to construct a chronological framework for the aeolian dune.In addition,the sizes of grains were analyzed for identifying factors influencing the winter monsoon during the Medieval Warm Period (MWP) and the Little Ice Age (LIA) in this area.The results showed that the deposition of the aeolian dune was closely related to variations in the winter monsoon intensity.The changes of the winter monsoon were similar to the tendency of the East Asian winter monsoon,although there were several sub-fluctuations.From an overall perspective,the winter monsoon was strengthened during the MWP (1050–1300) .The results of a power spectrum analysis showed that the intensity of the East Asian winter monsoon is correlated with sunspot activity. 展开更多
关键词 coastal dune Optically Stimulated Luminescence Medieval Warm Period Little ice age winter monsoon
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Oxygen and hydrogen isotope ratios of chert from the Sixtymile Formation in Grand Canyon National Park,USA:a warm palaeoclimate,freshwater deposit
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作者 Ray Kenny 《Acta Geochimica》 EI CAS CSCD 2017年第2期250-259,共10页
New oxygen and hydrogen isotope ratios of chert from middle, intraformational breccias, and upper breccia members of the Sixtymile Formation(SMF) in eastern Grand Canyon National Park(AZ) yield palaeoclimate estim... New oxygen and hydrogen isotope ratios of chert from middle, intraformational breccias, and upper breccia members of the Sixtymile Formation(SMF) in eastern Grand Canyon National Park(AZ) yield palaeoclimate estimates between 27 and 33℃. The isotopic compositions of cherts define a domain approximately parallel to the meteoric water line when plotted on a δD–δ-(18)O diagram; these data indicate that meteoric water was involved during formation of the chert. In thin section, the absence of interlocking mega quartz(〉35 lm) and silicafilled fractures and veins, along with preserved micromorphological silica fabrics, suggest that the chert has not been permeated by later hydrothermal fluids. Petrographic observations in thin section such as cyclic silica precipitation phases and glaebular micromorphologic fabrics lend support to the interpretation that meteoric waters were involved during chert precipitation. The post 742 Ma SMF has been correlated with diamictite(transition) beds of the Kingston Peak Formation(CA), which in turn have been interpreted to have been deposited during the Sturtian Ice Age(-750–700 Ma). Absence of facetted and striated clasts and other diagnostic glaciogenic features in the SMF,an unconformable contact with the stratigraphically older Chuar Group, coupled with warm palaeotemperature data inferred from stable isotope values of chert, tentatively suggest that deposition of sediment in the SMF likely did not take place during the Sturtian Ice Age. 展开更多
关键词 Oxygen and hydrogen isotope ratios Chert Sturtian ice age Grand Canyon Sixtymile Formation Snowball Earth
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The past,present,and future of the Siberian Grouse(Falcipennis falcipennis)under glacial oscillations and global warming
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作者 Wendong Xie Kai Song +2 位作者 Siegfried Klaus Jon E.Swenson Yue-Hua Sun 《Avian Research》 SCIE CSCD 2022年第1期57-63,共7页
Global climate change has a significant effect on species,as environment conditions change,causing many species'distributions to shift.During the last three million years,the earth has experienced glacial oscillat... Global climate change has a significant effect on species,as environment conditions change,causing many species'distributions to shift.During the last three million years,the earth has experienced glacial oscillations,forcing some species to survive in ice-free refugia during glacial periods and then disperse postglacially.In this study,by assessing the potential distribution of Siberian Grouse(Falcipennis falcipennis),we used Global Circular Models and Representative Concentration Pathways to model their pattern of range changes during glacial oscillations and the potential impact of present global warming.We used 158 location records of Siberian Grouse to generate a full climate model using 19 bioclimate variables in MaxEnt.We discarded variables with a correlation coefficient larger than 0.8 and relatively lower modeling contributions between each pair of correlated variables.Using the remaining variables,we created a normally uncorrelated simple climate model to predict the possible distribution of Siberian Grouse from the most recent Ice Age to present and to 2070.Then we added geographical data and the human interference index to construct a multiple factor full model to evaluate which were important in explaining the distribution of Siberian Grouse.The Total Suitability Zone(P≥0.33)of Siberian Grouse is about 243,000km^(2) and the Maximum Suitability Zone(P≥0.66)is 36,000km^(2) and is confined to the Russian Far East.Potential habitat modeling suggested that annual precipitation,annual mean temperature,and the distance from lakes are the most explanatory variables for the current distribution of Siberian Grouse.The distribution center moved to the southeast during the Last Glacial Maximum and spread back to the northwest after the ice melted and temperatures rose.The total area range of Siberian Grouse experienced a dramatic loss during the Last Glacial Maximum.Global warming is presently forcing the Siberian Grouse to migrate northward with a contraction of its range.There is an urgent need to protect its habitat,because little of its Maximum Sustainable Zone is protected,although there are some large reserves in that area. 展开更多
关键词 Climate change Falcipennis falcipennis ice age refugia Last glacial maximum
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