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北天山西段中强地震应力触发作用初步研究 被引量:3
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作者 王琼 聂晓红 唐丽华 《内陆地震》 2007年第2期119-128,共10页
计算了新疆北天山西段1944年以来部分5级以上地震产生的静态库仑破裂应力变化(ΔCFS),分析该区先发生的中强震产生的累加库仑应力变化以及单个中强地震对后续地震的触发作用。研究中依据静态库仑破裂应力变化的空间分布确定后续地震活... 计算了新疆北天山西段1944年以来部分5级以上地震产生的静态库仑破裂应力变化(ΔCFS),分析该区先发生的中强震产生的累加库仑应力变化以及单个中强地震对后续地震的触发作用。研究中依据静态库仑破裂应力变化的空间分布确定后续地震活动的可能增强区范围,应用累积贝尼奥夫应变研究增强区内中等地震活动的加速矩释放特征,定量论证中强震产生的库仑应力变化对后续地震产生的影响的可靠性。结果表明,北天山西段多数中强震产生的ΔCFS有利于其邻区后续中强震的发生,其中正ΔCFS区是后续中强地震的可能发生地点,该区中强震产生的库仑应力变化作用的时空影响范围分别为几天至几十年1、00 km范围内,这为未来地震趋势判定提供了依据。 展开更多
关键词 北天山西段 静态库仑破裂应力变化 加速矩释放模型
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利用GPS数据探讨北天山东段现今地壳应变场演化特征--重新认识2016年呼图壁M_(S)6.2地震 被引量:2
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作者 纪凯 唐红涛 《地震工程学报》 CSCD 北大核心 2022年第4期879-889,895,共12页
利用2009—2011、2011—2013、2013—2015年GPS形变资料,借助最小二乘配置方法、位移与应变的偏导关系,计算获得北天山东部应变场的动态演化结果,重新认识北天山东段构造区的现今活动特征,探讨应变场三个周期空间分布特征与2016年呼图壁... 利用2009—2011、2011—2013、2013—2015年GPS形变资料,借助最小二乘配置方法、位移与应变的偏导关系,计算获得北天山东部应变场的动态演化结果,重新认识北天山东段构造区的现今活动特征,探讨应变场三个周期空间分布特征与2016年呼图壁6.2级地震的内部联系。结果表明:(1)区域地壳运动速率与应变场强度在时间上表现为“弱-强-弱”的变化特征,主应变率以NNW或NNE向的主压应变为主,第一、三周期N-S向主压应变较小,约(1~2)×10^(-8)/a,第二周期变化显著增强,约(1~6)×10^(-8)/a,第三周期滑动速率显示北天山东段呈“强[(2.2±0.4)mm/a]-弱(不明显)-强[(3.0±1.0)mm/a]”的右旋走滑特征;(2)地震可能更易发生在面应变率场等值线四象限中心区域或正、负过渡区的高密度梯度带内部,这可能是地震孕育过程中利用GPS资料观测到的形变前兆;(3)强震更易发生在剪应变率(最大剪应变率)的高值区或边缘区;(4)相对于面应变率与最大剪应变率等应变场物理量,主应变率更适用于在块体运动方向与性质上给出解释。 展开更多
关键词 北天山东段 应变场 呼图壁M_(S)6.2地震 震源机制解 等值线分布
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新疆北天山西段P波、S波衰减特征研究 被引量:1
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作者 高朝军 夏爱国 +3 位作者 张志鹏 赵石柱 周康云 候赛因.赛买提 《内陆地震》 2014年第4期319-326,共8页
针对2008年1月至2011年12月发生在新疆北天山西段的地震事件,分析新源、温泉和巴仑台3个台站记录到的波形资料,采取尾波归一化方法,计算出P、S波在多个频率点f的衰减系数Q-1P、Q-1S,利用最小二乘法拟合得到Q-1=Q0fη,得到该区域P波衰减... 针对2008年1月至2011年12月发生在新疆北天山西段的地震事件,分析新源、温泉和巴仑台3个台站记录到的波形资料,采取尾波归一化方法,计算出P、S波在多个频率点f的衰减系数Q-1P、Q-1S,利用最小二乘法拟合得到Q-1=Q0fη,得到该区域P波衰减系数和S波衰减系数。结果表明,新源研究区关于P波、S波的衰减指数为-0.982 1、-0.978 1;温泉研究区关于P波、S波的衰减指数为-1.049 7、-0.773 8;巴仑台研究区关于P波、S波的衰减指数为-0.870 0、-0.956 8。与中国云南地区关于P波、S波衰减结果相比,新源研究区域与云南的禄劝研究区地下介质衰减特性比较一致。 展开更多
关键词 北天山西段 尾波归一化 P波衰减指数 S波衰减指数
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新疆境内北天山西段地震活动图象的定量研究 被引量:3
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作者 周仕勇 《内陆地震》 1992年第4期335-339,共5页
文中应用带状集中度C_b值、信息熵H值及缺信量I_q值,定量分析了近年来新疆境内北天山西段小震活动图象的异常特征。结果表明,在这个构造较为复杂的研究区内,C_b、H、I_q值的变化均能较好的反映中、强震的短——临异常信息。
关键词 北天山西段 地震活动性 地震图象
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浅析北天山西段与南天山中东段地震活动关系 被引量:1
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作者 潘振生 《内陆地震》 2008年第2期170-176,共7页
对比分析了北天山西段与南天山中东段的地震活动关系,发现1935年以来两区地震活动水平相近,中强以上地震具有交替活动的特征,且有一定的成组性南北迁移的规律。时空扫描分析发现,北天山西段新源—温泉附近地区的中小地震集中活动对南天... 对比分析了北天山西段与南天山中东段的地震活动关系,发现1935年以来两区地震活动水平相近,中强以上地震具有交替活动的特征,且有一定的成组性南北迁移的规律。时空扫描分析发现,北天山西段新源—温泉附近地区的中小地震集中活动对南天山东段中强地震的发生具有一定的前兆意义,南天山东段的4级地震频度的减小与北天山西段5级以上地震有一定的对应关系。并在一定程度上对两区域地震活动存在的以上规律和对应关系进行了分析。 展开更多
关键词 北天山西段 山中东段 中强地震 前兆异常
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北天山西段喇嘛苏铜矿中酸性岩体岩石化学特征及其地质意义
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作者 毛政利 成功 +1 位作者 赖健清 彭省临 《地质找矿论丛》 CAS CSCD 2018年第1期93-99,共7页
喇嘛苏铜矿区中酸性岩体的皮科克指数、里特曼指数、赖特指数,均指示其中酸性岩体属于钙碱性岩系的范围;分异指数平均值为77.57,说明岩体的分异演化程度较为彻底;固结指数平均值为12.01,显示出岩体的岩浆分异程度较高;长英指数和铁镁指... 喇嘛苏铜矿区中酸性岩体的皮科克指数、里特曼指数、赖特指数,均指示其中酸性岩体属于钙碱性岩系的范围;分异指数平均值为77.57,说明岩体的分异演化程度较为彻底;固结指数平均值为12.01,显示出岩体的岩浆分异程度较高;长英指数和铁镁指数均反映岩体的分离结晶作用程度中等。在MF—FL分异趋势图上,样品点基本呈连续分布,说明岩体的演化是连续的;在w(Na_2O)—w(K_2O)关系图上多数样品点落入I型花岗岩区域,可以认为本区花岗岩应为I型花岗岩。岩体的TiO_2含量平均为w(TiO_2)=0.28%,远低于中国及世界同类岩石;在戈蒂尼指数与里特曼指数对数值的关系图上,几乎所有的样品点均落在消减带火山岩区,由此可以推断,本区斑岩体应形成于与俯冲作用有关的消减带上。在多阳离子的R1—R2关系图中,多数样品点落在地壳熔融花岗岩-同碰撞的花岗岩区,少数样品点落在其它区域,这说明了岩浆在演化过程中同化混染了围岩。 展开更多
关键词 喇嘛苏铜矿 中酸性岩体 结晶环境 分异演化 消减带 北天山西段 新疆
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论北天山西段奥陶纪含笔石地层及笔石群的划分 被引量:2
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作者 乔新东 《新疆地质》 CAS CSCD 1989年第1期81-90,共10页
笔者把下奥陶统新二台组分为三个岩性段,下奥陶统新建五个笔石带、北天山西段以笔石带化石的混生为显著特点,除巳公布的Cardiograptus-Oncograptus混生外,Anisograptus和Triograptus的混生为一新的例证、Anisograptus和Triograptus在我... 笔者把下奥陶统新二台组分为三个岩性段,下奥陶统新建五个笔石带、北天山西段以笔石带化石的混生为显著特点,除巳公布的Cardiograptus-Oncograptus混生外,Anisograptus和Triograptus的混生为一新的例证、Anisograptus和Triograptus在我国华南它们分别是新厂期X_1和X_2的笔石带化石,而在果子沟它们上延到相当华南新厂期X_3的层位、此两笔石属的个别分子可继续上延到Tetragraptus(Etagraptus)approximatus带的底部和T.fruticosus带、风沟组被厘定为中奥陶统下部.在科古琴地区发现有中奥陶统上部层位和晚奥陶世地层. 展开更多
关键词 笔石 混合 笔石带 下奥陶统新二台组 中奥陶统下部风沟组 中奥陶统上部层位 晚奥陶世地层 北天山西段
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核光谱望远镜阵列河外巡天:扩展钱德拉南天与钱德拉北天深场星表
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作者 张天逸 薛永泉 《中国科学技术大学学报》 CAS CSCD 北大核心 2023年第7期44-54,70,共12页
我们提出一种常规且可靠的方法以获得核光谱望远镜阵列在扩展钱德拉南天深场与钱德拉北天深场的星表。核光谱望远镜阵列在扩展钱德拉南天深场的观测天区覆盖了30'×30'大小的面积,其最深曝光时长在3-24 keV波段作晕影修正... 我们提出一种常规且可靠的方法以获得核光谱望远镜阵列在扩展钱德拉南天深场与钱德拉北天深场的星表。核光谱望远镜阵列在扩展钱德拉南天深场的观测天区覆盖了30'×30'大小的面积,其最深曝光时长在3-24 keV波段作晕影修正后可达230 ks,共有58个源被探测到并收录在本工作的星表中;核光谱望远镜阵列在钱德拉北天深场的观测天区覆盖了7'×10'大小的面积,其最深曝光时长在3-24 keV波段作晕影修正后可达440 ks,共有42个源被首次探测到并收录在本工作的星表中。通过与钱德拉X射线天文台在对应天区的星表结果进行交叉匹配后,我们发现核光谱望远镜阵列星表中的源与它们在钱德拉X射线望远镜星表中的对应体有着大致相当的流量,由此验证了本工作两个星表的可靠性。我们的两个星表通过完全一致的方法制作而成且公开释放,这为后续涉及这两个天区的研究提供了一个统一的平台。我们的源探测方法为核光谱望远镜阵列其他河外巡天的星表制作提供了一种系统的方法。 展开更多
关键词 核光谱望远镜阵列 河外巡 X射线源 扩展钱德拉南深场 钱德拉北天深场
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北魏天兴元年(398)高句丽人入北魏考 被引量:1
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作者 常乐 金洪培 《佳木斯职业学院学报》 2020年第1期176-178,180,共4页
与北魏政权同时并存的有朝鲜半岛的高句丽政权,双方起初的接触并不是来自双边政府层面的对话往来。北魏道武帝于天兴元年(398)从后燕故地一带迁徙了一批包括高句丽人在内的徙民至新都平城,也正是道武帝此举,北魏同高句丽之间才就此拉开... 与北魏政权同时并存的有朝鲜半岛的高句丽政权,双方起初的接触并不是来自双边政府层面的对话往来。北魏道武帝于天兴元年(398)从后燕故地一带迁徙了一批包括高句丽人在内的徙民至新都平城,也正是道武帝此举,北魏同高句丽之间才就此拉开接触的帷幕。通过考察是年这批迁至北魏的高句丽民的原因、数量、受安置情况及日后去向,可见北魏初年对流入中原的高句丽人所采取的举措,及这批高句丽人对北魏政权建立之初所带来的影响。 展开更多
关键词 兴元年 道武帝 高句丽人 迁徙
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从天鹿北路优化设计谈重大项目的前期管理
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作者 胡锦荣 《广东公路交通》 2015年第4期89-92,共4页
针对广州天鹿北路改扩建工程施工图设计中存在大面积填埋水库水面、大面积开挖山体、桩板墙深水围堰施工难度大、砍伐天鹿神榄及工程造价较高等问题,建设单位组织有关专家进行详细评审及论证,开展了调整设计线位、缩窄道路横断面、桩板... 针对广州天鹿北路改扩建工程施工图设计中存在大面积填埋水库水面、大面积开挖山体、桩板墙深水围堰施工难度大、砍伐天鹿神榄及工程造价较高等问题,建设单位组织有关专家进行详细评审及论证,开展了调整设计线位、缩窄道路横断面、桩板墙改为半幅桥等设计优化工作。优化实施后的桥隧段和谐地穿越在天鹿湖山水之间。该项目取得了良好的经济效益、环境效益和社会效益,在总结该项目优化过程经验的同时,建议从六方面加强重大项目的前期管理工作。 展开更多
关键词 鹿路改扩建工程 优化设计 前期管理
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天麻属——广东省兰科植物一新记录属(英文) 被引量:5
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作者 田怀珍 李宏庆 杨智凯 《热带亚热带植物学报》 CAS CSCD 北大核心 2010年第5期488-490,共3页
报道广东兰科植物一新记录属——天麻属(Gastrodia R.Br.),提供北插天天麻(G.peichatieniana S.S.Ying)的详细形态描述及照片,该种原记录仅分布于中国台湾。
关键词 麻属 兰科 新记录
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天池风景区
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《畜牧市场》 2003年第6期17-17,
【正】 天池,地处天山博格达峰北侧,位于阜康县南偏东40余公里,距乌鲁木齐市110公里。“天池”一名来自乾降48年(公元1783年)乌鲁木齐都统明亮的题《灵山天池统凿水渠碑记》。天池湖面海拔1900余公尺,南北长3千余米,东西最宽处1500余米... 【正】 天池,地处天山博格达峰北侧,位于阜康县南偏东40余公里,距乌鲁木齐市110公里。“天池”一名来自乾降48年(公元1783年)乌鲁木齐都统明亮的题《灵山天池统凿水渠碑记》。天池湖面海拔1900余公尺,南北长3千余米,东西最宽处1500余米,旺水时面积达4. 展开更多
关键词 池风景区 山博格达峰 乌鲁木齐都统 博格达山 乌鲁木齐市 国家重点风景名胜区 阜康县 北天山东段 时面积 南偏东
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Abell团角分布的二级矩,三级矩以及空间三点相关函数
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作者 景益鹏 张家铝 《天文学报》 CSCD 北大核心 1989年第3期241-248,共8页
本文用"胞内计数"方法对北天区的富度R≥1的Abell团角分布的二级矩和三级矩作了统计,并由此得到了Abell团的空间三点相关函数;同时,本文还对D≤4,R≥1的Abell团红移样品的三点相关函数进行了统计.这些统计分析得到的结果与通... 本文用"胞内计数"方法对北天区的富度R≥1的Abell团角分布的二级矩和三级矩作了统计,并由此得到了Abell团的空间三点相关函数;同时,本文还对D≤4,R≥1的Abell团红移样品的三点相关函数进行了统计.这些统计分析得到的结果与通过估计红移值对四组子样品进行统计分析所得到的结果是一致的,从而进一步说明,星系和Abell团的三点相关函数可用同一个普遍的标度形式来描述. 展开更多
关键词 北天 团角 级矩 空间 相关函数
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Advances in Grassland Ecosystem Research in Northern Tibetan Plateau 被引量:25
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作者 武建双 沈振西 张宪洲 《Agricultural Science & Technology》 CAS 2009年第3期148-152,共5页
With the aggravation of global change, the response and adaptation of the unique ecosystem in Qinghai-Tibet Plateau to global change have been increasingly concerned by scientific community day by day, which makes the... With the aggravation of global change, the response and adaptation of the unique ecosystem in Qinghai-Tibet Plateau to global change have been increasingly concerned by scientific community day by day, which makes the sensitivity and fragility of this ecosystem in response to global change widely recognized by scholars. On the basis of introducing the present research process on the degenerate mechanisim, measures of and approaches to recovery, carbon cycle and primary productivity toward global change, we put forward several propositions on studying the alpine grassland ecosystem in Northern Tibetan Plateau. 展开更多
关键词 Northern Tibetan Plateau Grassland degeneration Global changes Carbon cycle Primary productivity
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Spatial connectivity and distribution of landscape type in the natural secondary forests of eastern mountainous region,northeast China——a case study of Mao'ershan region in Heilongjiang Province
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作者 李淑娟 隋玉正 +2 位作者 冯海清 王凤友 李玉文 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期141-144,i003,共5页
Mao'ershan region is representative in the natural secondary forested region of the eastern mountainous region, northeast China. The landscape nearest neighbor index and landscape connectivity index were calculate... Mao'ershan region is representative in the natural secondary forested region of the eastern mountainous region, northeast China. The landscape nearest neighbor index and landscape connectivity index were calculated with ARC/INFO software for Mao'ershan region. The spatial distribution of the landscape of the region was analyzed. The results showed that the landscape connectivity index of non-woodland was significantly higher than that of woodland. The landscape connectivity index of natural forest was nearly equal to zero, which means its fragmentation degree is high. The nearest neighbor index of plantation was lower than that of natural forest and non-forestland. Among the man-made forests, the distance index of the coniferous mixed plantation is the lowest, and its pattern is nearly glomeration. The landscape pattern of natural forest presented nearly random distribution. Among non-forest land, the distance index of cut blank was the lowest, and its pattern was also nearly glomeration. Keywords Landscape type - Landscape pattern - Nearest neighbor index - Landscape connectivity index - Natural secondary forest - Northeast China CLC number S759.92 Document code A Foundation item: This paper was supported by the Key Project of State Department of Science Technology (2002BA515B040).Biography: LI SHu-juan (1977), female. Lecture in Ocean University of China, Qingdao 266003, P. R. China.Responsible editor: Zhu Hong 展开更多
关键词 Landscape type Landscape pattern Nearest neighbor index Landscape connectivity index Natural secondary forest Northeast China
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Water Requirements and Irrigation Scheduling of Spring Maize Using GIS and CropWat Model in Beijing-Tianjin-Hebei Region 被引量:18
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作者 FENG Zhiming LIU Dengwei ZHANG Yuehong 《Chinese Geographical Science》 SCIE CSCD 2007年第1期56-63,共8页
Due to the over use of available water resources, it has become very important to define appropriate strategies for planning and management of irrigated farmland. In this paper, Beijing-Tianjin-Hebei (Jing-Jin-Ji) reg... Due to the over use of available water resources, it has become very important to define appropriate strategies for planning and management of irrigated farmland. In this paper, Beijing-Tianjin-Hebei (Jing-Jin-Ji) region was chosen as the case study area for its special political and economic status and its severe water problem. To achieve effective planning, the information about crop water requirements, irrigation withdrawals, soil types and climatic conditions were obtained in the study area. In the meantime, a GIS method was adopted, which extends the capabilities of the crop models to a regional level. The main objectives of the study are: 1) to estimate the spatial distribution of the evapotranspiration of spring maize; 2) to estimate climatic water deficit; 3) to estimate the yield reduction of spring maize under different rainfed and irrigated conditions. Based on the water deficit analysis, recommended supplemental irrigation schedule was developed using CropWat model. Compared to the rainfed control, the two or three times of supplemental water irrigated to spring maize at the right time reduced the loss of yield, under different scenarios. 展开更多
关键词 spring maize climatic water deficit irrigation schedule
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Spatial and temporal variability of open biomass burning in Northeast China from 2003 to 2017 被引量:5
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作者 WANG Lili JIN Xin +4 位作者 WANG Qinglu MAO Huiqin LIU Qiyang WENG Guoqing WANG Yuesi 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第3期240-247,共8页
Open biomass burning(OBB)has a significant impact on the heavy haze pollution in Northeast China(NEC)in recent years,which requires the investigation of the spatiotemporal variations of OBB with different vegetation t... Open biomass burning(OBB)has a significant impact on the heavy haze pollution in Northeast China(NEC)in recent years,which requires the investigation of the spatiotemporal variations of OBB with different vegetation types to better monitor and control OBB in NEC.The MODIS C6 fire and land cover products,together with the emissions inventory from the Global Fire Assimilation System,were used in this study.The changes in the total number of MODIS fire points in NEC from 2003 to 2017 demonstrated a fluctuating but generally rising trend,with a peak during 2013–2017.Most fire points concentrated in two key periods,i.e.March–April(37%)and October–November(46%).The total number of crop residue burnings in March–April was basically slightly fluctuating and increased sharply from 2013,whilst the number in October–November had a fluctuating and upward trend until 2015,when a decline appeared.The amount of OBB in March–April was higher than that in October–November during 2016–17.OBB in Heilongjiang Province comprised a major proportion of all fires,which accounted for 70.7%from 2003 to 2017;however,the proportion was only 66.2%during 2013–2017.The largest proportion of all fires was in cropland(90.8%),then forest(5.3%)and grassland(3.1%).The cumulative emissions of fine particulate matter,nitrogen oxides,and ammonia from agricultural open burning in NEC reached 78.43 Gg,24.9 Gg,and 13.7 Gg for March–April during 2013–17,respectively,which were close to those in October–November. 展开更多
关键词 Open biomass burning MODIS Northeast China open agricultural residual burning
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Analysis of interprovincial trade embodied carbon emissions in Beijing-Tianjin-Hebei and surrounding provinces: based on constructed MRIO Model 被引量:4
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作者 Jianhui Cong Qingyan Liu +3 位作者 Jidong Kang Wenju Li Xiaopei Wang Man Li 《Chinese Journal of Population,Resources and Environment》 2017年第1期71-79,共9页
The interprovincial trade embodied carbon emissions plays an important role in the national emission reduction target among China's provinces. Furthermore, it will affect the smooth start-up of the national carbon... The interprovincial trade embodied carbon emissions plays an important role in the national emission reduction target among China's provinces. Furthermore, it will affect the smooth start-up of the national carbon trade market as well as the implementation of targets in 2030 for dealing with the climate change. Based on constructed MRIO model, this paper analyzes the embodied carbon emission trade flows among Beijing, Tianjin, Hebei and surrounding regions such as Shanxi, Shaanxi, and Inner Mongolia. The results indicate that six provinces have formed different patterns of carbon trade balance, where Beijing, Tianjin, and Hebei provinces are in a deficit position, while the other three provinces are in a surplus position.Beijing, Tianjin, and Hebei have transferred part of the carbon emissions to the other three provinces, which shows greater heterogeneity among various provinces and provincial different sectors. On basis of the conclusions, this paper puts forward some suggestions on provincial decomposition, responsibility distribution, and provincial collaborative reduction for national emission reduction targets. 展开更多
关键词 Trade embodied carbonemissions multiregionalinput-output model carbontrade balance carbontransfer
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Recent Climate Trends on the Northern Slopes of the Tianshan Mountains, Xinjiang, China 被引量:3
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作者 ZHANG Hongfeng OUYANG Zhiyun ZHENG Hua WANG Xiaoke 《Journal of Mountain Science》 SCIE CSCD 2009年第3期255-265,共11页
In arid regions, mountains fulfill important ecological and economic functions for the surrounding lowlands. In the scenario of global warming, mountain ecosystems change rapidly, especially in the arid region of nort... In arid regions, mountains fulfill important ecological and economic functions for the surrounding lowlands. In the scenario of global warming, mountain ecosystems change rapidly, especially in the arid region of northwestern China. This paper provides an assessment of the changes in temperature and precipitation in the historical records of climate on the northern slopes of the eastern Tianshan Mountains. A Mann-Kendall nonparametric trend and Sen's tests are employed to analyze the interannual changes and innerannual variability in temperature and precipitatiofi in the regions of low to high altitude. The present study finds that the largest increases in annual temperature are observed at stations in the low altitude regions. The significant increasing trends in temperature tend to occur mainly in late winter and early spring at stations from middle to high altitude, but in summer and autumn at stations of low altitudes. The increasing trends in annual precipitation are found from the middle to high altitude areas, but decreasing trends are found in the low altitude areas. The significant increasing trends in precipitation occur mostly in winter and earlier spring at stations from the middle to high altitudes, while the increasing and decreasing trend coexists at stations of low altitude with most of the significant trend changes occurring in March, June and August. 展开更多
关键词 Mountainous region Climate change Temperature PRECIPITATION China
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A Numerical Study of the Urban Intensity Effect on Fog Evolution in the Beijing-Tianjin-Hebei Region 被引量:5
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作者 LIANG Zhao-Ming GAO Shou-Ting SUN Ji-Song 《Atmospheric and Oceanic Science Letters》 2012年第3期240-245,共6页
The influence of urban intensity on fog evolution in the Beijing-Tianjin-Hebei (BTH) region (China) is investigated numerically with the the Weather Research and Forecasting (WRF) model coupled with the urban canopy p... The influence of urban intensity on fog evolution in the Beijing-Tianjin-Hebei (BTH) region (China) is investigated numerically with the the Weather Research and Forecasting (WRF) model coupled with the urban canopy parameterization-building energy model (UCP- BEM) urban physics scheme. The experiments were designed with a focus on the influence of different urban intensities, which are represented by a different fractional coverage of natural land, buildings, and energy consumption inside buildings in an urban environment. The results of this study indicate that urban areas notably influence fog evolution when natural land is reduced to a small fraction (e.g., less than 10%). Developed land changes fog evolution through urban effects. Higher urban intensity (HUI) generally results in warmer temperatures and lower wind speeds throughout the day, while inhibiting morning specific humidity loss and afternoon specific humidity gain because of the HUI effect on surface heat flux, surface roughness, and surface moisture flux. HUI leads to later and weaker liquid water content formation, with a higher liquid water content base, primarily due to its effect on near surface temperatures. This finding implies that HUI may inhibit the conditions for fog formation. In addition, urban areas with equal natural and developed land coverage seem to greatly enhance the upward surface moisture flux, which is attributed to the combination of a relatively large potential evaporation on developed land and an ample moisture supply from natural land. As a result, the specific humidity increases in the afternoon. 展开更多
关键词 numerical study urban intensity effect FOG the Beijing-Tianjin-Hebei region
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