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过去千年气候变化的数值模拟研究进展 总被引：4，自引：1，他引：3
在阐述千年气候变化研究意义的基础上,围绕着如何利用气候系统模式来对过去千年的气候变化进行归因模拟、以理解其中自然和人为因素的作用问题,总结和评述了国际上相关研究进展,进一步归纳了千年气候变化数值模拟中亟待解决的科学问题,重点包括千年气候演变中自然变率特征时段(即中世纪暖期和小冰期)与人类活动影响时段(即20世纪气候变暖)的气候差别,在中世纪暖期、小冰期和20世纪气候变暖这3个特征时段上,自然变化和人类活动影响的作用与机制比较、中国过去千年气候演变的模拟等,随后,扼要介绍了国家自然科学基金重大项目"中国地区树轮及千年气候变化研究"之课题"中国千年气候变化数值模拟与机理研究"的主要研究内容. 相似文献
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利用中等复杂程度模式MPM2进行的多情景1000年气候模拟试验和全球海气耦合气候模式ECHOG进行的1000年长时间积分气候模拟试验结果,分析了过去1000年全球气候变化特征及其与各强迫因子变化的关系,并与部分温度重建资料作了对比,探讨了近千年气候变化的原因和驱动因子。模拟和重建结果均反映出了大约出现在1000～1300年的中世纪暖期、1300～1850年的小冰期和1860年之后的全球升温期。对于1300～1850年的小冰期和1860年之后的升温期,模拟和重建的趋势基本一致,尤其是1670～1710年Maunder太阳黑子最小期时,模拟和重建结果吻合很好。各因子及其组合的强迫试验表明,在不同典型气候时期,强迫因子的作用是不一样的。1000～1300年的中世纪暖期,模拟与重建资料存在一定的位相差异和幅度差异。从整体上来看,模式得出的温度距平值要小于重建温度距平值。在1000年尺度上,太阳辐射、火山活动和温室气体对全球温度变化都有重要意义,但表现的时间不同。在最近百年尺度上,温室气体含量的变化对温度的变化起着相对更为重要的作用。 相似文献
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全球过去千年典型暖期温度空间格局重建 总被引：1，自引：0，他引：1
利用过去两千年全球变化研究网络(PAGES 2k network)最新公布的501条代用记录,重建了全球过去千年全年平均温度空间格局的演化特征,对比分析了中世纪暖期及其最暖100年与20世纪现代暖期、中世纪暖期和小冰期最暖30年与20世纪最近30年的年平均温度空间模态异同.结果显示,在世纪尺度上,现代暖期与历史上中世纪暖期的温度异常空间格局大致相同,变化幅度也在大部分区域相当,但从年代际尺度上,最近30年的升温比过去千年中世纪暖期和小冰期两个典型时期都明显.值得一提的是北大西洋中高纬度海温变化与上述特征并不相同,在年代际和世纪尺度上小冰期和中世纪暖期海温均高于20世纪.可能原因是大西洋经圈翻转环流在中世纪暖期、小冰期和20世纪现代暖期等3个特征时段对太阳辐射、火山活动和温室气体等外强迫的响应不同. 相似文献
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利用全球海气耦合气候模式ECHO-G的近千年连续积分资料,选取与降水关系较好的东亚夏季风指数,对不同气候特征时期的东亚环流及季风影响因子进行了探讨.结果表明用海陆热力差异定义的东亚夏季风指数Isun在年际尺度上较好地体现了长江流域及华北地区降水的变化,而利用850 hPa纬向风场定义的指数Iwang在年代际尺度上较好地体现了长江流域的降水变化.从不同气候特征时期的环流来看,中世纪暖期夏季风最强,东亚大陆降水明显偏多,现代暖期夏季风较之有所减弱,而小冰期则是夏季风最弱的时期,东亚大陆的降水明显偏少.不同气候特征时期夏季风指数与海温的相关表明,ENSO事件对东亚夏季风的影响在现代暖期有所增强,而与外部强迫因子的相关揭示出中世纪暖期有效太阳辐射变化是影响东亚夏季风变化的主要因子,现代暖期则是温室气体对夏季风的影响更重要. 相似文献
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本文通过对青藏高原上所钻取的古里雅冰芯和青海都兰树轮高分辨率气候变化记录的对比,分析了过去近2 000a来的气候变化特征.结果表明:1)这两个地区过去2 000a来温度都在波动中逐渐上升,展示了气候逐渐变暖的趋势.进入20世纪以来,气候显著变暖,并有加速变暖的趋势;2)树轮和冰芯均明显地记录了小冰期的3次冷期,其出现的时间基本上一致.小冰期并不是过去2 000a来的最寒冷的时期.冰芯和树轮记录均表明公元初的寒冷程度要大于小冰期;3)古里雅冰芯所记录的温度和降水量揭示出,过去近2 000a来的降水和温度变化的总趋势是正相关关系;但在短时间尺度上,温度和降水的变化并不同步.这主要表现在两个方面,一是温度长期变化中的低频波动频率要大于降水,二是虽然温度和降水的变化在百年级时间尺度上有正相关性,但降水的变化要滞后于温度变化50～100a;4)同时周期分析表明,古里雅冰芯中的δ180和积累量以及都兰树轮记录的变化周期大多数与太阳活动有关,表明青藏高原地区冷、暖、干、湿变化的主要驱动力可能是太阳活动的变化;5)对这两记录的对比研究也揭示了气候变化的区域差异.如中世纪暖期在都兰树轮记录中很强而在古里雅冰芯记录中很弱,而都兰树轮记录中,中世纪暖期以后至1 800A.D.在波动中变冷,但在古里雅冰芯记录中这一时期在波动中变暖. 相似文献
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中纬度亚洲地区存在主要受季风环流影响的东南部湿润地区(简称季风区)和主要受西风环流控制的内陆干旱区(包括青藏高原北部高寒干旱区,简称西风区)。根据对近年来新发表的气候变化记录证据梳理总结,发现西风区在中—晚全新世气候湿润,与亚洲季风在早—中全新世强盛的格局显著不同。过去千年的西风区中世纪暖期干旱,而小冰期相对湿润,与此相对,万象洞石笋氧同位素记录则显示季风降水在中世纪暖期时整体处于高值,在小冰期处于低值段。在近百年,尤其是近50a,西北干旱区湿度增加,而季风影响范围内的西北东部和华北等地变得更干。不仅如此,在分属西风和季风影响区的青藏高原北部和南部,年代际—百年尺度上降水变化也表现出反相位关系。据此我们提出,亚洲中部西风带控制区在现代间冰期从数千年到年代际的各个时间尺度上均存在不同于季风区的湿度(降水)变化模式,称之为现代间冰期气候变化的西风模式。 相似文献
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文章对在青藏高原腹地可可西里地区的苟鲁错封闭湖盆中心部位获取深1m的湖底沉积岩芯进行137Cs,210Pb测年和高分辨率的碳酸盐含量、地球化学等方面的分析。结果表明:该湖泊沉积记录揭示出青藏高原腹地在近1000年时间尺度上气候变化的模式呈冷湿和温(暖)干组合为主。该岩芯覆盖了过去近1000年左右的时间尺度,其碳酸盐含量、元素地球化学的变化对中世纪暖期和小冰期的3次冷期和期间的多次暖期都有明显反映。从苟鲁错沉积记录来看,中世纪暖期的盛期处于公元1060～1140年;小冰期第1次冷期在公元1140～1340年,但在1250～1290年存在1次暖波动;第2次冷期在公元1510～1680年,但在1580～1590年和1610年左右存在暖波动;第3次冷期在公元1790～1900年;暖期主要在公元1340～1510年和1680～1790年间,但在公元1400年、1410年左右和1440～1480年间以及1710～1740年存在冷波动;20世纪暖期和全球记录相一致。该湖泊记录与古里雅冰芯记录和祁连山树轮记录以及我国东部气候历史记录都有较好的可对比性,只是在起迄年代上还存在一些差异有待深入研究。 相似文献
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文章对在青藏高原腹地可可西里地区的苟鲁错封闭湖盆中心部位获取深1m的湖底沉积岩芯进行137Cs,210Pb测年和高分辨率的碳酸盐含量、地球化学等方面的分析。结果表明:该湖泊沉积记录揭示出青藏高原腹地在近1000年时间尺度上气候变化的模式呈冷湿和温(暖)干组合为主。该岩芯覆盖了过去近1000年左右的时间尺度,其碳酸盐含量、元素地球化学的变化对中世纪暖期和小冰期的3次冷期和期间的多次暖期都有明显反映。从苟鲁错沉积记录来看,中世纪暖期的盛期处于公元1060～1140年;小冰期第1次冷期在公元1140～1340年,但在1250～1290年存在1次暖波动;第2次冷期在公元1510～1680年,但在1580～1590年和1610年左右存在暖波动;第3次冷期在公元1790～1900年;暖期主要在公元1340～1510年和1680～1790年间,但在公元1400年、1410年左右和1440～1480年间以及1710～1740年存在冷波动;20世纪暖期和全球记录相一致。该湖泊记录与古里雅冰芯记录和祁连山树轮记录以及我国东部气候历史记录都有较好的可对比性,只是在起迄年代上还存在一些差异有待深入研究。 相似文献
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《Quaternary International》1999,53(1):35-47
Several lines of evidence concur to explain the climatic fluctuations that occurred in the central region of Argentina during the last millennium. The investigation was advanced in two ways: on the one hand, a geographic model was elaborated; and on the other, a temporal sequence for various climatic situations was developed. During the last 1000 yr, two significant events related to global changes occurred: the Medieval Warm Period (MWP) and the Little Ice Age (LIA). The Medieval Warm Period was characterized by a humid and warm climate in the plains and recession of the Andean glaciers. In contrast, during the Little Ice Age the plains had temperate, semi-arid to arid climates, and Andean glaciers advanced. In the western region, the fluvial-lacustrine systems were more extensive during cold events (LIA) and contracted during warm events (MWP). In contrast, in the eastern region the fluvial-lacustrine systems showed a diminution during cold events and increased their extent during warm episodes. During the LIA, the occurrence of two cold pulses separated by an intermediate period has been established. The first cold pulse extended from the beginning of the XV century to the end of the XVI century; the second cold pulse (the main one) began at the beginning of the XVIII century and lasted until the beginning of the XIX century. Both cold pulses can be related to the Spörer and Maunder Minimums respectively. These climatic changes modified the landforms, influenced the vegetation distribution and were one of the main factors for control of human activities during the last 1000 yr. 相似文献
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过去2 000年气候变化是深入了解过去全球气候演化机制、探索人类活动与环境演化相互关系的重要依据。我国西南地区是气候变化与人类文明研究的重要区域，获取更多记录资料对深入理解两者之间的相互关系尤为重要。本文以云南省腾冲县北海湿地沉积物为研究对象，利用AMS 14C测年建立年代学序列，利用烧失量、粒度分析结果建立了该地区过去2 050年气候演变序列。结果表明:2 050 cal. a B.P.~1 400 cal. a B.P.期间尤其是最后阶段气候寒冷干旱；1 400 cal. a B.P.~750 cal. a B.P.期间相对温暖湿润；750 cal. a B.P.~300 cal. a B.P.期间寒冷干旱；300 cal. a B.P.以来温暖偏湿。通过与云南地区人类活动记录对比发现，该地区人口的增长、社会政权的更替在一定程度上受自然气候环境演化的影响，南诏和大理民族政权的建立主要集中在相对温暖湿润的中世纪暖期；此外，云南地区近2 000年来人口数量的变化与气候变化同样呈现出较好的一致性。 相似文献
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Liang-Chi Wang Jiunn-Tzong Wu Teh-Quei Lee Pei-Fen Lee Su-Hwa Chen 《Journal of Asian Earth Sciences》2011,40(6):51-1170
In this study, we synthesized the fossil pollen data from 10 lake sediments and 2 land cores to integrate the alteration of forest covered areas in northern Taiwan with changes in humidity and temperature over the last 2000 years. The abundance of arboreal pollen, fern spores and Tsuga pollen in the pollen and spore assemblages were used as indicators. Our results suggested that the climate in northern Taiwan was stably cool and dry during 2000–1000 cal. yr BP, but changed to wet and warm during 1000–500 cal. yr BP, which corresponded to the Medieval Warm Period (MWP). In addition, an increased density and dispersal of Tsuga pollen corresponding to 500–200 cal. yr BP was observed, which corresponded to the Little Ice Age (LIA). In recent years, a decline in Tsuga pollen density and increased fern spore density has been observed, which indicates an increase in temperature associated with elevated rainfall. Based on the synthesized data set, we conducted GIS mapping of such changes in the north of Taiwan over time. The results revealed that the temporal and spatial climate changes could be inferred from the palynological GIS mapping method, and that the fluctuations in temperature over time matched well with the global climate events, including MWP, LIA and recent warming. 相似文献
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湖泊沉积,特别是内陆高山封闭湖泊沉积是古气候研究的重要载体,可以高分辨率、敏感地记录连续的古气候环境变化。选取祁连山中段天鹅湖沉积岩芯TEB孔的10个陆生植物残体进行AMS 14C测年并建立年代框架,结合对总有机碳（TOC）含量、矿物成分及元素相对含量等指标的分析结果,重建了天鹅湖3 500年来的沉积环境变化特征。初步研究结果表明:碳酸盐含量变化主要受控于地下水补给量的变化,进而反映区域降水量,1 534 BC~1 300 AD期间,天鹅湖区降水呈减少的趋势,尤其是中世纪暖期（720~1 300 AD）,是3 500年来最干旱的时期;小冰期开始于1 300 AD,共出现三次降水较多的时期,1 600~1 730 AD为小冰期最盛期。受西风环流影响,天鹅湖沉积记录了该区域中世纪暖期相对暖干,而小冰期较为冷湿的变化特征。同时,该湖记录的小冰期气候相比于中世纪暖期更不稳定。 相似文献
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MA LONG WU JINGLU YU HONG ZENG HAIAO JILILI ABUDUWAILI 《Boreas: An International Journal of Quaternary Research》2011,40(3):518-524
Ma, L., Wu, J., Yu, H., Zeng, H. & Abuduwaili, J. 2011: The Medieval Warm Period and the Little Ice Age from a sediment record of Lake Ebinur, northwest China. Boreas, Vol. 40, pp. 518–524. 10.1111/j.1502‐3885.2010.00200.x. ISSN 0300‐9483. Lake Ebinur, Xinjiang, northwest China, is a closed‐basin, shallow lake that responds rapidly to changes in the ratio of precipitation to evaporation (P/E). A sediment record spanning the last 1500 years was obtained from the lake. We used δ18O and δ13C in bulk carbonate, and δ13C of organic matter in the lake sediments to infer environmental changes in the Ebinur region during the Medieval Warm Period (MWP) and the Little Ice Age (LIA). Decreased δ18O values of carbonate largely reflect an enhanced P/E ratio within the basin and a higher lake level. Bulk carbonates with higher δ13C values are deposited during periods when lake‐water pH is high, while lower δ13C values reflect a lower pH in the water column. δ13C in organic matter is associated with the amount of precipitation. The results indicate that the Ebinur region experienced a dry MWP and a wet LIA, although the MWP and LIA were warm and cold periods, respectively, as expected. Furthermore, the MWP and LIA were hydrologically complex and cannot be characterized as uniformly wet or dry. Peak wet periods are recorded in the sediment core around AD 1000, 1400 and 1700, and a dry event also occurred in the period of temperature change within the LIA (cold to warm around AD 1500). A comparison of the Lake Ebinur data with proxy records for the strength of the Siberian High and climate proxy indicators suggests that precipitation in the Ebinur region was a consequence, in part, of an enhanced Siberian High during the LIA. 相似文献
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Michel Magny Odile Peyron Boris Vannière Bruno Vermot-Desroches 《Quaternary Research》2011,75(1):45-54
This paper presents quantitative climate estimates for the last millennium, using a multi-proxy approach with pollen and lake-level data from Lake Joux (Swiss Jura Mountains). The climate reconstruction, based on the Modern Analogue Technique, indicates warmer and drier conditions during the Medieval Warm Period (MWP). MWP was preceded by a short-lived cold humid event around AD 1060, and followed by a rapid return around AD 1400 to cooler and wetter conditions which generally characterize the Little Ice Age (LIA). Around AD 1450 (solar Spörer minimum), the LIA attained a temperature minimum and a summer precipitation maximum. The solar Maunder minimum around AD 1690 corresponded at Joux to rather mild temperatures but maximal annual precipitation. These results generally agree with other records from neighbouring Alpine regions. However, there are differences in the timing of the LIA temperature minimum depending on the proxy and/or the method used for the reconstruction. As a working hypothesis, the hydrological signal associated with the MWP and LIA oscillations at Lake Joux may have been mainly driven by a shift around AD 1400 from positive to negative NAO modes in response to variations in solar irradiance possibly coupled with changes in the Atlantic meridional overturning circulation. 相似文献
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Climate change is one of the most active research fields currently, which has attracted extensive attention from the international community. In order to better understand the development situation and research status of international climate change science, in this paper we took the SSCI and SCI databases as data sources, collected the relevant literatures since 1900 based on the key words related to climate change, and made some statistics and analysis of the literatures of the past one hundred years to reveal the development process of climate change research as well as the development and evolution of its research topics and hot spots. The results showed that the climate change research began in the late 18 th century and early 19 th century, and the academic debate about global warming and global cooling started in the early 1970s. The international programs and projects led by a range of international organizations and intergovernmental bodies have contributed significantly to the rapid development of climate change research. The United States and the United Kingdom have long been the core countries of climate change research. The proportion of Chinese papers has risen rapidly in the last decade. The intensity and scope of scientific research cooperation are constantly expanding. Current research focuses on climate model/modeling, climate simulation, climate policy, climate sensitivity, climate change impacts, climate change adaptation, climate change mitigation, and rate of climate change. 相似文献