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Science China Earth sciences 2005年第Z2期48卷 230-245页

作者： YANG Dongzhen, XU Xiangde, liu Xiaoduan, XU Qing, ding Guoan, CHENG Xinghong, CHEN Huailiang, ZHOU Huaigang, WANG Zhenfa, WANG Wenyan Key Laboratory of Atmospheric Chemistry, Center for Atmosphere Watch and Services, chinese {3. of meteorological {3., CMA, beijing 100081, China Key Laboratory of meteorological Disasters, CAMS, beijing 100081, China National Center for Geological Testing, beijing 10003., China meteorological Bureau of Henan Province, Zhenzhou 450000, China Shangdianzi Background Atmospheric Pollution Observation Station, Miyun County, beijing 101507, China Key Laboratory of Atmospheric Chemistry Center for Atmosphere Watch and Services Chinese Academy of Meteorological Sciences CMA Beijing 100081 China Key Laboratory of meteorological Disasters CAMS Beijing 100081 China National Center for Geological Testing Beijing 100037 China meteorological Bureau of Henan Province Zhenzhou 450000 China Shangdianzi Background Atmospheric Pollution Observation Station Miyun County Beijing 101507 China

The comprehensive impact of atmospheric dry deposition and wet deposition and the pollution sources of farmlands, mining areas, and towns along the Baihe River on the water quality of Miyun reservoir is investigated from the angle of the complex sources of air-soil-water pollution processes, in the context of the 1990-2001 precipitation chemical data at Shangdianzi station-a WMO regional background air pollution monitoring station 15 km far from the Miyun reservoir, in conjunction with the atmospheric dry deposition and wet deposition data of the 2002 -2003.beijing City Air Pollution Observation Field Experiment (BECAPEX). Analysis results suggest that the major ions in precipitation in the Miyun reservoir region in this period were SO 42-, NO 3., NH4+ and Ca2+; wet acid deposition quantity of Miyun reservoir in the summer half year (April to September) was greater than the quantity in the winter half year (October to March), and the annual wet acid deposition in the reservoir exhibited a rising trend with the mean 103..45 t, the maximum 1766.3. t occurred in 1996, and the minimum 604.02 t in 1994; the long-term averaged pH of atmospheric precipitation in the Miyun reservoir region was 5.20, i.e. weakly acidic, and the interannual variation of pH values displayed a falling trend. pH values of water body at various depths in the Miyun reservoir were all greater than 7.0, but they exhibited vertical and horizontal nonhomogeneity, and at the same region pH decreased vertically with depth; the 2002 and 2003.annual dustfalls in the Miyun reservoir were 13.13.08 t and 3.77.64 t, respectively, and the spring dustfall was the number one in a year, accounting for the 61.91% and 44.56% of the annual totals of 2002 and 2003. respectively. Because the atmospheric dry deposition and wet depositions contain multiple types heavy metal elements and harmful elements, they to some extent exacerbated the eutrophication, acidification and potential heavy metal pollution of the reservoi

关键词： Miyun reservoir, water quality, Shangdianzi regional background air pollution observation station, atmospheric dry deposition/wet deposition, water system pollution.

Reconciled estimation of Antarctic ice sheet mass balance and contribution to global sea level change from 1996 to 2021

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Science China Earth sciences 2024年第11期67卷 3562-3578页

作者： Rongxing LI Guojun LI Gang HAI Huan XIE Yuan CHENG Wei CHEN Xiangbin CUI Minghu ding Chunchun GAO Tong HAO Changqing KE Chuanjin LI Jin LI Yan liu Jiangjun RAN Jiawen REN Qiang SHEN Yunzhong SHEN Hongling SHI Songyun WANG Zemin WANG Jingang ZHAN Baojun ZHANG Min ZHONG Chunxia ZHOU Center for Spatial Information Science and Sustainable Development Applications Tongji University College of Surveying and Geo-informatics Tongji University Institute for the Conservation of Cultural Heritage School of Cultural Heritage and Information Management Shanghai University College of Resource Environment and Tourism Hubei University of Arts and Science Polar Research Institute of China State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences College of Geodesy and Geomatics Shandong University of Science and Technology School of Geography and Ocean Science Nanjing University Shanghai Astronomical Observatory Chinese Academy of Sciences State Key Laboratory of Remote Sensing Science Faculty of Geographical Science Beijing Normal University Department of Earth and Space sciences Southern University of Science and Technology State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences State Key Laboratory of Geodesy and Earth's Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences Center for Space Research University of Texas at Austin chinese Antarctic Center of Surveying and Mapping Wuhan University School of Geospatial Engineering and Science Sun Yat-sen University

The Antarctic Ice Sheet（AIS） has been losing ice mass and contributing to global sea level rise（GSLR）. Given its mass that is enough to cause ～58 m of GSLR, accurate estimation of mass balance trend is critical for AIS mass loss monitoring and sea level rise forecasting. Here, we present an improved approach to reconciled solutions of mass balance in AIS and its regions from multiple contributing solutions using the input-out, altimetric, and gravimetric methods. In comparison to previous methods, such as IMBIE 2018, this approach utilizes an adaptive data aggregation window to handle the heterogeneity of the contributing solutions, including the number of solutions, temporal distributions, uncertainties, and estimation techniques. We improved the regression-based method by using a two-step procedure that establishes ensembled solutions within each method（input-output, altimetry, or gravimetry） and then estimates the method-independent reconciled solutions. For the first time, 16contributing solutions from 8 chinese institutions are used to estimate the reconciled mass balance of AIS and its regions from1996 to 2021. Our results show that AIS has lost a total ice mass of ～3.13.253.Gt during the period, an equivalent of～8.9±0.7 mm of GSLR. There is a sustained mass loss acceleration since 2006, from 88.1±3.6 Gt yr-1during 1996–2005 to 13..7 ±8.4 Gt yr-1during 2006–2013.and further to 157.0±9.0 Gt yr-1during 2014–2021. The mass loss signal in the West Antarctica and Antarctic Peninsula is dominant and clearly presented in the reconciled estimation and contributing solutions, regardless of estimation methods used and fluctuation of surface mass balance. Uncertainty and challenges remain in mass balance estimation in East Antarctica. This reconciled estimation approach can be extended and applied for improved mass balance estimation in the Greenland Ice Sheet and mountain glacier regions.

关键词： Antarctic Ice Sheet Ice mass loss acceleration Sea level rise Reconciled estimation

快速动脉自旋标记成像在脑胶质瘤中的临床应用价值

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中华放射学杂志 2024年第5期58卷 529-533页

作者：张艳玲徐慕榕徐晓璐丁金立段云云刘亚欧江裕华卓芝政首都医科大学附属北京天坛医院放射科北京100070 军事科学院军事医学研究院卫生勤务与血液研究所北京100850 首都医科大学附属北京天坛医院神经外科北京100070

目的探讨快速动脉自旋标记(ASL)成像应用于脑胶质瘤成像的可行性。方法前瞻性纳入2021年5月至2022年12月就诊于首都医科大学附属北京天坛医院的脑胶质瘤患者,所有患者均接受MR快速ASL(扫描时间1 min)和常规ASL(扫描时间4 min 3. s)检查... 详细信息

目的探讨快速动脉自旋标记(ASL)成像应用于脑胶质瘤成像的可行性。方法前瞻性纳入2021年5月至2022年12月就诊于首都医科大学附属北京天坛医院的脑胶质瘤患者,所有患者均接受MR快速ASL(扫描时间1 min)和常规ASL(扫描时间4 min 3. s)检查,得到脑血流分数(CBF)图。由2名放射科医师独立对2种序列扫描所得的CBF进行定性(人工判读肿瘤区CBF信号的高低)和定量分析(提取肿瘤实体区和水肿区等区域CBF平均值)。采用Kappa检验对定性评估结果进行一致性分析;采用ICC对定量结果进行一致性分析。结果共纳入脑胶质瘤患者3.例。2名医师采用快速ASL判断肿瘤区低灌注、等灌注、高灌注分别为1、6、23.和0、5、25例;采用常规ASL判断肿瘤区低灌注、等灌注、高灌注均为0、9、21例;快速ASL与常规ASL定性分析的一致性均较高(Kappa分别为0.83.、0.850)。定量分析显示,快速ASL与常规ASL测量脑不同部位的CBF值具有较高一致性(ICC为0.940~0.994)。结论快速ASL可替代常规ASL用于脑胶质瘤组织灌注评估,有助于胶质瘤的临床诊断。

关键词：磁共振成像快速动脉自旋标记脑胶质瘤灌注成像

Influence of Human Activities on Wintertime Haze-Related meteorological Conditions over the Jing–Jin–Ji Region

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Engineering 2021年第8期7卷 1185-1192页

作者： Ying Xu Yanju liu Zhenyu Han Botao Zhou yihui ding Jie Wuc Tongfei Tian Rouke Li Jing Wang National Climate Center China Meteorological AdministrationBeijing 100081China Collaborative Innovation Center on Forecast and Evaluation of meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China School of Geography and Environmental Engineering Gannan Normal UniversityGanzhou 341000China Camford Royal School Beijing 100093China Climate and Environment Modeling Lab Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China

This work analyzes and discusses the influence of human activities on the meteorological conditions related to winter haze events in beijing,Tianjin,and Hebei(i.e.,the Jing-Jin-Ji region)during 1961-2016,using the results of two numerical simulation experiments based on the Community Atmosphere Model version 5.1.1(http://***/models/cesm1.0/cam/docs/ug5_1_1/***)used in the international Climate Variability and Predictability Programme(CLIVAR)Climate of the 20th Century Detection and Attribution Project(C20C+D&A).The results show that,under the influence of human activities,the changes in dynamical and thermal meteorological conditions related to winter haze events in the Jing–Jin–Ji region are conducive to the formation and accumulation of haze,and prevent the diffusion of *** dynamical conditions mainly include the obvious weakening of the East Asian winter monsoon(EAWM)and the enhancement of the near-surface anomalous southerly *** thermal conditions include the obvious increase in surface temperature,and the enhancement of water vapor transport and near-surface *** relative contribution of dynamical and thermal conditions to the variation of haze days in the Jing-Jin-Ji region is analyzed using statistical *** results show that the contribution of human activities to the increase of haze days in the Jing-Jin-Ji region is greater than that of natural forcing for the study *** be specific,the dynamical meteorological factors contribute more to the haze days than the thermal meteorological *** contribution of thermal meteorological factors is basically the same in both scenarios.

关键词： meteorological conditions Human activities Haze Jing-Jin-Ji region

The Warm Arctic-Cold Eurasia Pattern and Its Key Region in Winter in CMIP6 Model Simulations

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Advances in Atmospheric sciences 2023年第12期40卷 2138-2153,I0002-I0006页

作者： Liang ZHAO Yunwen liu yihui ding Qingquan LI Wei DONG Xinyong SHEN Wei CHENG Haoxin YAO Ziniu XIAO State Key Laboratory of Numerical Modeling for Atmosphere sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjing 210044China Neijiang meteorological Bureau Neijiang 641000China China meteorological Administration National Climate CenterBeijing 100081China Key Laboratory of Geoscience Big Data and Deep Resource of Zhejiang Province School of Earth SciencesZhejiang UniversityHangzhou 310058China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China beijing Institute of the Applied Meteorology Beijing 100029China

An enhanced Warm Arctic-Cold Eurasia(WACE)pattern has been a notable feature in recent winters of the Northern ***,divergent results between model and observational studies of the WACE still *** study evaluates the performance of 3. climate models participating in the Coupled Model Intercomparison Project Phase 6(CMIP6)in simulating the WACE pattern in winter of 1980-2014 and explores the key factors causing the differences in the simulation capability among the *** results show that the multimodel ensemble(MME)can better simulate the spatial distribution of the WACE pattern than most single *** that can/cannot simulate both the climatology and the standard deviation of the Eurasian winter surface air temperature well,especially the latter,usually can/cannot simulate the WACE pattern *** mainly results from the different abilities of the models to simulate the range and intensity of the warm anomaly in the Barents Sea-Kara seas(BKS)*** analysis shows that a good performance of the models in the BKS area is usually related to their ability to simulate location and persistence of Ural blocking(UB),which can transport heat to the BKS region,causing the warm Arctic,and strengthen the westerly trough downstream,cooling central ***,simulation of UB is key and significantly affects the model’s performance in simulating the WACE.

关键词： warm Arctic-cold Eurasia pattern Arctic amplification CMIP6 simulation evaluation extreme climate blocking highs

基于北京3.5m气象铁塔的城市冠层以上湍流强度垂直分布特征分析与推算方法评估

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建筑结构 2024年第13期54卷 71-80页

作者：丁伟宸师宇刘磊胡非中国科学院大气物理研究所大气边界层物理和大气化学国家重点实验室北京100029 中国科学院大学北京100049

为了研究与风载荷密切相关的城市大气边界层湍流的垂直分布特征,利用北京3.5m气象铁塔的不同高度一年四季的湍流观测数据进行统计分析,重点对比分析了湍流强度剖面实测值和推算值。结果表明:采用《建筑结构荷载规范》(GB 50009-2012)推... 详细信息

为了研究与风载荷密切相关的城市大气边界层湍流的垂直分布特征,利用北京3.5m气象铁塔的不同高度一年四季的湍流观测数据进行统计分析,重点对比分析了湍流强度剖面实测值和推算值。结果表明:采用《建筑结构荷载规范》(GB 50009-2012)推荐的10m湍流强度和风廓线幂指数得到的湍流强度剖面推算值明显小于考虑了小风情况的实测值,荷载规范推荐参数不适用于发达城市边界层湍流强度剖面推算;采用实测风廓线幂指数和城市冠层内8m湍流强度实测值得到的湍流强度剖面推算值与实测值的相对误差达20%以上;采用实测风廓线幂指数和城市冠层之上的47m湍流强度实测值得到的湍流强度剖面推算值与实测值的相对误差小于9%。因此,以城市冠层之上的湍流强度实测值和实测风廓线幂指数为基础推算湍流强度剖面的方法能够得到比较接近于实测值的结果,此推算方法具有可行性与可靠性。

关键词：湍流强度风廓线高塔城市边界层

GPS TEC response to the 22 July 2009 total solar eclipse in East Asia

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GPS TEC response to the 22 July 2009 total solar eclipse in ...

天津冬季两个典型污染过程高浓度无机气溶胶成因及来源分析

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Feng ding,Weixing Wan,Baiqi Ning,Libo liu,Huijun Le,Guirong Xu, Min Wang,Guozhu Li,Yiding Chen,Zhipeng Ren,Bo Xiong,Lianhuan Hu, Xinan Yue,Biqiang Zhao,Fengqin Li,and Min Yang 1 {3. National Observatory of Space Environment,Institute of Geology and Geophysics,chinese academy of {3.,{3.,China. 2 Institute of Heavy Rain,China meteorological Administration, Wuhan,China. 3.Institute of Earthquake Science,China Earthquake Administration, {3.,China. 4 Graduate School of the chinese academy of {3.,{3.,China. 5 University Corporation for Atmospheric Research,Boulder,Colorado, USA.

[1]The longest total solar eclipse of this century occurred in East and South Asia on 22 July *** eclipse was accompanied with a medium magnetic storm,whose main phase onset occurred～27 min after the passage of the Moon’s umbral *** TEC data from 60 GPS stations,we construct differential TEC maps to investigate the ionosphere response to the solar eclipse in central China in the range of 26°N-3.°N, 108°E-118°E(i.e.,the magnetic latitude 15°N-25°N).During the eclipse’s totality,a "shadow" in the ionosphere shown as TEC depletion area was formed～100 km south of the Moon’s umbral path with a maximum decrease of 5 *** TEC depletion area moved eastward,following the movement of the totality area with a time lag of～10 min. Enhancements of TEC due to the storm are observed after the main phase *** relative drop of TEC due to the solar eclipse is evidently larger at lower latitudes than that at higher ones and around noontime than that in the *** modeling work,we find that the latitudinal dependence of the TEC response may result from latitudinal variation of magnetic inclination,which influences the diffusion of ionization among different ***,the local time dependence of TEC response is closely related to the local time variation of background atmosphere density,which affects the electron loss efficiency in the ionosphere.

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环境科学 2024年第5期45卷 2581-2595页

作者：卢苗苗韩素芹刘可欣唐晓孔磊丁净樊文雁王自发天津市环境气象中心天津300074 中国气象局‐南开大学大气环境与健康研究联合实验室天津300074 南开大学环境科学与工程学院天津市城市交通污染防治研究重点实验室天津300071 中国科学院大气物理研究所大气边界层物理和大气化学国家重点实验室北京100029 中国科学院大气物理研究所国际气候与环境科学中心北京100029 中国科学院大学地球与行星科学学院北京100049

无机气溶胶是天津冬季霾天出现的主要成分,研究挑选了2020年1月污染天中两个典型的高浓度无机气溶胶(SIA)过程(CASE1和CASE2),利用观测数据和耦合了在线污染物来源追踪方法的大气化学传输模式NAQPMS综合探究了气象要素、区域输送和化学... 详细信息

无机气溶胶是天津冬季霾天出现的主要成分,研究挑选了2020年1月污染天中两个典型的高浓度无机气溶胶(SIA)过程(CASE1和CASE2),利用观测数据和耦合了在线污染物来源追踪方法的大气化学传输模式NAQPMS综合探究了气象要素、区域输送和化学过程的影响.两个过程的ρ(SIA)均值分别为76.8μg·m^(−3.和66.0μg·m^(−3.,硝酸盐浓度高于硫酸盐和铵盐,均为硝酸盐为主导的污染过程.气象条件影响了无机气溶胶的生成,CASE1过程ρ(SIA)>80μg·m^(−3.对应的温度和相对湿度区间分别是[−6℃,0℃]、[2℃,4℃]和[50%,60%]、[80%,100%];CASE2过程对应的温度和相对湿度区间分别是[2℃,4℃]和[60%,70%].外来源对CASE1和CASE2过程SIA的平均贡献率为62.3.和22.1%,分别为区域传输主导和局地生成主导过程.CASE1本地排放对硝酸盐和硫酸盐的贡献分别为16.2μg·m^(−3.和8.2μg·m^(−3.,均高于外来源的贡献(3..7μg·m^(−3.和8.8μg·m^(−3.);CASE2过程本地排放对硝酸盐和硫酸盐的贡献分别为29.3.g·m^(−3.和25.1μg·m^(−3.,而外来源的贡献为8.1μg·m^(−3.和9.4μg·m^(−3..这表明CASE1本地生成和外来源输送贡献造成硝酸盐高于硫酸盐浓度,而CASE2仅本地源造成硝酸盐浓度高于硫酸盐.两个污染过程气相氧化反应是无机气溶胶生成的首要来源,贡献率分别为48.9%和57.8%;非均相反应也是重要过程,对SIA的贡献率分别为48.1%和42.2%;液相反应的影响小.

关键词：无机气溶胶气象因素区域传输化学过程天津

青藏高原草本沼泽植被净初级生产力时空变化及其对气候变化的响应

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生态学报 2024年第5期44卷 2115-2126页

作者：吴丽媛神祥金刘奕雯马蓉张佳琦丁辰吕宪国姜明中国科学院东北地理与农业生态研究所长春130102 中国科学院大学北京100049

青藏高原是我国重要的草本沼泽分布区,该地区草本沼泽对于东亚生态安全及碳循环具有重要的意义。植被净初级生产力(NPP)是反映生态系统固碳能力的重要指标,气候变化能够显著影响植被NPP。在全球气候变化背景下,青藏高原草本沼泽植被NPP... 详细信息

青藏高原是我国重要的草本沼泽分布区,该地区草本沼泽对于东亚生态安全及碳循环具有重要的意义。植被净初级生产力(NPP)是反映生态系统固碳能力的重要指标,气候变化能够显著影响植被NPP。在全球气候变化背景下,青藏高原草本沼泽植被NPP的时空变化及对气候响应机理尚不明确。利用2000―2020年NPP数据和气象数据,对青藏高原草本沼泽植被NPP的时空变化及其对气候变化的响应进行分析。研究表明:青藏高原草本沼泽植被NPP多年平均值为122.80 g C/m^(2),在2000—2020年青藏高原草本沼泽植被年NPP总体呈现显著增加趋势(0.79 g C m^(-2)a^(-1)),其中增加趋势最为显著的地区集中于研究区北部。研究发现青藏高原草本沼泽植被NPP主要受年均气温影响,年均降水对青藏高原草本沼泽植被NPP的影响并不显著。在不同季节,夏季和秋季升温均能够显著增加沼泽植被NPP,其中夏季夜晚最低温升高对青藏高原草本沼泽植被生长的促进作用比白天最高温升高更显著。在全球昼夜不对称增温背景下,未来模拟青藏高原草本沼泽植被NPP时,需重点关注白天和夜晚温度变化对草本沼泽植被生长的不同影响。研究结果有助于评估青藏高原草本沼泽植被固碳潜力,并为青藏高原沼泽生态保护提供科学依据。

关键词：草本沼泽植被净初级生产力气候变化青藏高原