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Variation of Surface Temperature during the last millennium in a Simulation with the FGOALS-gl Climate System Model

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Advances in Atmospheric Sciences 2013年第3期30卷 699-712页

作者：张洁 Laurent LI 周天军辛晓歌 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Laboratoire de Météorologie Dynamique/CNRS Université Paris 6 National Climate Center China Meteorological Administration

A reasonable past millennial climate simulation relies heavily on the specified external forcings, including both natural and anthropogenic forcing agents. In this paper, we examine the surface temperature responses to specified external forcing agents in a millennium-scale transient climate simulation with the fast version of LASG IAP Flexible Global Ocean-Atmosphere-Land System model （FGOALS-gl） developed in the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics （LASG/IAP）. The model presents a reasonable performance in comparison with reconstructions of surface temperature. Differentiated from significant changes in the 20th century at the global scale, changes during the natural-forcing-dominant period are mainly manifested in the Northern Hemisphere. Seasonally, modeled significant changes are more pronounced during the wintertime at higher latitudes. This may be a manifestation of polar amplification associated with sea-ice-temperature positive feedback. The climate responses to total external forcings can explain about half of the climate variance during the whole millennium period, especially at decadal timescales. Surface temperature in the Antarctic shows heterogeneous and insignificant changes during the preindustrial period and the climate response to external forcings is undetectable due to the strong internal variability. The model response to specified external forcings is modulated by cloud radiative forcing （CRF）. The CRF acts against the fluctuations of external forcings. Effects of clouds are manifested in shortwave radiation by changes in cloud water during the natural-forcing-dominant period, but mainly in longwave radiation by a decrease in cloud amount in the ant hropogenic- forcing-dominant period.

关键词： last millennium external forcing surface temperature cloud radiative forcing climate system model

Regional-scale Surface Air Temperature and East Asian Summer Monsoon Changes during the last millennium Simulated by the FGOALS-gl Climate System Model

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Advances in Atmospheric Sciences 2014年第4期31卷 765-778页

作者： MAN Wenmin ZHOU Tianjun State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science and Technology Climate Change Research Center Chinese Academy of Sciences

The spatial patterns and regional-scale surface air temperature （SAT） changes during the last millennium,as well as the variability of the East Asian summer monsoon （EASM） were simulated with a low-resolution version of Flexible Global Ocean-Atmosphere-Land-Sea-ice （FGOALS-gl） model.The model was driven by both natural and anthropogenic forcing agents.Major features of the simulated past millennial Northern Hemisphere （NH） mean SAT variations,including the Medieval Climate Anomaly （MCA）,the Little Ice Age （LIA） and the 20th Century Warming （20CW）,were generally consistent with the reconstructions.The simulated MCA showed a global cooling pattern with reference to the 1961-90 mean conditions,indicating the 20CW to be unprecedented over the last millennium in the simulation.The LIA was characterized by pronounced coldness over the continental extratropical NH in both the reconstruction and the simulation.The simulated global mean SAT difference between the MCA and LIA was 0.14°C,with enhanced warming over high-latitude NH continental regions.Consistencies between the simulation and the reconstruction on regional scales were lower than those on hemispheric scales.The major features agreed well between the simulated and reconstructed SAT variations over the Chinese domain,despite some inconsistency in details among different reconstructions.The EASM circulation during the MCA was stronger than that during the LIA The corresponding rainfall anomalies exhibited excessive rainfall in the north but deficient rainfall in the south.Both the zonal and meridional thermal contrast were enhanced during the MCA.This temperature anomaly pattern favored a stronger monsoon circulation.

关键词： last millennium surface air temperature spatial patterns regional-scale variation East Asian summer monsoon

Spatially explicit reconstruction of cropland cover for China over the past millennium

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Science China Earth Sciences 2023年第1期66卷 111-128页

作者： Fanneng HE Fan YANG Caishan ZHAO Shicheng LI Meijiao LI Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Research Institute of Yellow River Civilization and Sustainable Development&Collaborative Innovation Center on Yellow River Civilization Jointly Built By Henan Province and Ministry of Education Henan UniversityKaifeng 475001China University of Chinese Academy of Sciences Beijing 100049China School of Public Administration China University of GeosciencesWuhan 430074China College of Resources and Environment Shanxi University of Finance and EconomicsTaiyuan 030006China

Reconstructing historical land use and land cover change using explicit temporal,quantitative,and spatial information is not only the prerequisite for simulating long-term climate change and ecological effects but is also a scientific basis for comprehensively understanding the process and mechanism of anthropogenic land use alterations.Considering changes in historical borders and administrative divisions,a provincial cropland area dataset for China over the past millennium was created on the basis of existing estimations since the Song Dynasty.Land suitability for cultivation was then assessed by incorporating altitude,slope,soil texture,and the maximum potential productivity of climate.Subsequently,a gridding allocation model for cropland was constructed,and the provincial cropland area for 24 years over the past millennium was allocated into grids with a resolution of 10 km.The cropland area in China increased from 3.71×10^(7)ha in AD 1000 to 12.92×10^(7)ha in AD 1999,with a peak of 13.50×10^(7)ha in AD 1980.The total cropland area in China showed fluctuating increasing trends that can be divided into three phases:fluctuation without notable net change for AD 1000–1290,slow increase for AD 1290–1661,and rapid increase for AD 1661–1999.Spatially,cropland intensified in the middle-lower reaches of the Yellow and Yangtze Rivers and expanded to mountainous and frontier areas over the last millennium.Specifically,over the entire period,the fractional cropland areas(FCAs)in the middle-lower reaches of the Yellow and Yangtze Rivers increased by 1.4 and 0.8 times,respectively.Since the mid-Qing Dynasty,large-scale land reclamation expanded to areas of low reclamation in southwest and northeast China.The FCAs for southwest and northeast China increased from 2.13%and 0.55%in AD 1661 to 18.00%and 26.61%in AD 1999,respectively.For AD 1661–1999,the proportion of cropland increased by 55%in the hills and low mountains and 27%in the middle and high mountains.The comparison with remote sensing cropland data shows that the gr

关键词： Land use and land cover change Historical cropland Gridding reconstruction China last millennium

Global mean temperature changes during the last millennium

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Progress in Natural Science:Materials International 2002年第12期 42-46页

作者： GONG Daoyi Beijing 100875 Bering Normal University China Key Laboratory of Environ-mental Change and Natural Disaster

A synthetic study is made on the global or hemispheric mean temperature series for the last millennium worked out by Mann et al., Jones et al,, Crowley and Lowery, and Briffa. The global mean temperature series reconstructed by using proxy data at 30 sites by Wang et al. and simulations from AD 1000 to 2000 by energy balance model are described and compared with the series of others. Wang’s series gives greater variability and shows the highest correlation coefficient (0. 83) with the simulation results. Uncertainties in the reconstructions and simulations are discussed. The errors in reconstructing a global mean temperature series according to 30 sites as used in the research are estimated. Wang s series indicate that temperature average for the 11th century is higher than the mean of the last millennium. It infers that the Medieval Warm Period predominated to some extent over the globe. However, the 20th century is no doubt the warmest century during the last millennium.

关键词： last millennium temperature changes Medieval Warm Period Little Ice Age modern climate warming.

Evaluation of multidecadal and longer-term temperature changes since 850 CE based on Northern Hemisphere proxy-based reconstructions and model simulations

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Science China Earth Sciences 2020年第8期63卷 1126-1143页

作者： Jianglin WANG Bao YANG Jingyun ZHENG Xuezhen ZHANG Zhiyuan WANG Miao FANG Feng SHI Jingjing LIU Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100049China College of Geography and Environmental Science Zhejiang Normal UniversityJinhua 321004China Northwest Institute of Eco-Environment and Resource Chinese Academy of SciencesLanzhou 730000China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China

The temperature variability over multidecadal and longer timescales(e.g., the cold epochs in the late 15 th, 17 th, and early 19 th centuries) is significant and dominant in the millennium-long, large-scale reconstructions and model simulations;however, their temporal patterns in the reconstructed and simulated temperature series are not well understood and require a detailed assessment and comparison. Here, we compare the reconstructed and simulated temperature series for the Northern Hemisphere(NH) at multidecadal and longer-term timescales(>30 years) by evaluating their covariance, climate sensitivity and amplitude of temperature changes. We found that covariances between different reconstructions or between reconstructions and simulations are generally high for the whole period of 850–1999 CE, due to their similar long-term temporal patterns. However,covariances between different reconstructions or between reconstructions and simulations steadily decline as time series extends further back in time, becoming particularly small during Medieval times. This is related to the large uncetainties in the reconstructions caused by the decreased number of proxy records and sample duplication during the pre-instrumental periods.Reconstructions based solely on tree-ring data show higher skill than multiproxy reconstructions in capturing the amplitude of volcanic cooling simulated by models. Meanwhile, climate models have a shorter recovery(i.e., lag) in response to the cooling caused by volcanic eruptions and solar activity minima, implying the lack of some important feedback mechanisms between external forcing and internal climate processes in climate models. Amplitudes of temperature variations in the latest published tree-ring reconstructions are comparable to those of the multiproxy reconstructions. We found that the temperature difference between the Medieval Climate Anomaly(950–1250 CE) and the Little Ice Age(1450–1850 CE) is generally larger in proxybased reconstructions than in model simulations, but the reason i

关键词： Temperature changes Multidecadal and longer-term variability Northern Hemisphere last millennium

High-resolution patterns of palaeoenvironmental changes during the Little Ice Age and the Medieval Climate Anomaly in the northwestern Iberian Peninsula

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Geoscience Frontiers 2020年第5期11卷 1461-1475页

作者： Daniel Castro Martin Souto Maria Isabel Fraga Eduardo Garcia-Rodeja Sebastian Perez-Diaz Jose Antonio Lopez Saez Xabier Pontevedra-Pombal Dpto.Botanica Fac.BioloxiaUniversidade de Santiago de CompostelaGaliciaSpain Dpto.Edafoloxia e Quimica Agricola Fac.BioloxiaUniversidade de Santiago de CompostelaGaliciaSpain Dpto.Geografia Urbanismo y Ordenacion Del TerritorioETS CaminosCanales y PuertosUniversidad de CantabriaSpain GI Arqueobiologia Instituto de HistoriaCCHS–CSICMadridSpain

to identify plant macrofossils,estimate peat humification and calculate hydroclimatic indices based on current bog species,with the overall aim of determining the climate conditions associated with evolution of the bog during the Medieval Climate Anomaly and the Little Ice Age.These proxies,together with historical and climate data,proved to be good indicators of the changes in bog surface wetness.Analysis:of the core led to identification of 9 different periods:two corresponding to the so-called Medieval Climate Anomaly(930 to 1345 AD,1075–665 calibrated years before present[cal.yr BP]);four corresponding to the Little Ice Age(1345 to 1905 AD;665–105 cal yr BP);and three corresponding to the last century(1905 to 2000 AD).The findings revealed a generally dry climate that lasted until the 14th century,followed by a transition to a long period with a more humid,but characteristically very variable climate,which ended at the beginning of the 20th century and was followed by a rapid transition to more humid conditions and finally,a change to drier conditions.The Medieval Climate Anomaly was indicated by the abundance of dry-adapted mosses(Leucobryum glaucum,Hypnum cupressiforme)and characterized by warm dry conditions and high levels of peat humification,with alternating wet phases.The LIA period was dated by a large abundance of Sphagnum species(an indicator of wetness)and a gradual increase in the humification index.However,four different climate phases were differentiated in this period.High-resolution reconstruction of the evolution of the CVM bog and the multiproxy approach have together enabled a more detailed identification of climatic variations in this area,which are generally consistent with the global models,as well as better definition of the elusive climatic oscillations in the last millennium and confirmation of the importance of local modulation of global models.The study provides new information and a detailed chronology of climatic events that will help to refine local modulation of the climate evol

关键词： last millennium Raised bog Plant macrofossil Humification analysis Southwest Europe Climate change

A 1000-year record of vegetation change and wildfire from maar lake Erlongwan in northeast China

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A 1000-year record of vegetation change and wildfire from ma...

A 1000-yr record of environmental change in NE China indicated by diatom assemblages from maar lake Erlongwan

中国古生物学会孢粉学会第九届二次学术年会

作者：李杰 Anson W.Mackay Yan Zhang Jingjing Li School of Earth Sciences China University of Geosciences Environmental Change Research Centre Department of Geography University College London School of Aerospace Tsinghua University

A high-resolution(very 20 yrs)pollen and charcoal record from Erlongwan maar lake(EML)documents the vegetation history and fire activity of the Long Gang region(northeast China)over the past millennium.The age-depth model is based on Cs,Pb measurements,and one calibrated AMSC date at the base of the core.For much of the record,vegetation was dominated by a mixed conifer-hardwood forest.Pollen and charcoal concentrations reveal considerable

关键词： Pollen Charcoal Wild Fire last millennium Erlongwan Maar Lake

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A 1000-yr record of environmental change in NE China indicat...