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太阳黑子和ENSO对日本吉野川流域水文要素影响 被引量:19
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作者 董林垚 张平仓 +2 位作者 刘纪根 童晓霞 谢浩 《水科学进展》 EI CAS CSCD 北大核心 2017年第5期671-680,共10页
剖析"太阳-气候-水资源"体系作用机制对区域水资源科学管理具有重要科学意义。利用相关分析、主成分分析和小波分析方法,探究太阳黑子运动和厄尔尼诺(ENSO)对日本吉野川流域降雨、地表径流和地下水位影响。研究结果表明:太阳... 剖析"太阳-气候-水资源"体系作用机制对区域水资源科学管理具有重要科学意义。利用相关分析、主成分分析和小波分析方法,探究太阳黑子运动和厄尔尼诺(ENSO)对日本吉野川流域降雨、地表径流和地下水位影响。研究结果表明:太阳黑子活动和ENSO对研究区域水文过程显著影响分别发生在11 a和2~7 a周期上;太阳黑子运动能量以ENSO为"媒介"作用于流域降水和河川径流,但对地下水位波动影响不明显;太阳黑子活动在不同时频域对研究区域水文过程产生"直接"和"间接"影响,太阳黑子的"直接"影响可能通过调制ENSO外的气候模态来实现,其"间接"作用则通过"ENSO-西太平洋副高-东亚环流-水汽运动"系统作用实现。 展开更多
关键词 太阳黑子 厄尔尼诺 降水 径流 地下水 吉野川
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高阶电离层延迟对GPS双差观测值和基线向量的影响 被引量:6
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作者 朱春春 李征航 +1 位作者 屈小川 申小平 《大地测量与地球动力学》 CSCD 北大核心 2015年第1期81-86,共6页
用RINEX HO软件计算GPS载波相位观测值中的高阶(二阶和三阶)电离层延迟,在此基础上组成GPS双差观测值中的高阶电离层延迟(ΔIH)p,qi,g。讨论了(ΔIH)p,qi,g与地磁纬度、基线长度、基线方向及太阳活动水平间的关系。在其他条件均相同的... 用RINEX HO软件计算GPS载波相位观测值中的高阶(二阶和三阶)电离层延迟,在此基础上组成GPS双差观测值中的高阶电离层延迟(ΔIH)p,qi,g。讨论了(ΔIH)p,qi,g与地磁纬度、基线长度、基线方向及太阳活动水平间的关系。在其他条件均相同的情况下,用Bernese 5.0软件分别对进行了高阶电离层延迟改正的观测值和未进行高阶电离层延迟改正的观测值进行基线解算,求得高阶电离层延迟对基线向量解的影响ΔbH。结果表明,ΔbH的数值很小,在一般情况下可忽略不计。ΔbH与基线长度及太阳活动水平等因素间并无必然联系,但随着时段的减小,ΔbH会随之增大。 展开更多
关键词 高阶电离层延迟 GPS双差观测值 太阳活动水平 地磁纬度 基线向量解
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ENSO Index Variations and Links with Solar and Volcanic Activity
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作者 Valentina V. Zharkova Irina Vasilieva 《Natural Science》 2024年第4期25-44,共20页
In this paper, we investigated the Oceanic Niño Index (ONI), for simplicity called in this paper an El Nino Southern Oscillation (ENSO) index in 1950-2023 by applying the wavelet spectral transform and the IBM SP... In this paper, we investigated the Oceanic Niño Index (ONI), for simplicity called in this paper an El Nino Southern Oscillation (ENSO) index in 1950-2023 by applying the wavelet spectral transform and the IBM SPSS correlations analysis. ONI follows the three months’ current measurements of the average temperature of the sea surface in the East-Central tropical part of the Pacific Ocean nearby the international line of the date change over the average sea surface temperature over the past 30 years. The ENSO index is found to have a strong (>87%) correlation with the Global Land-Ocean Temperature (GLOT). The scatter plots of the ENSO-GLOT correlation with the linear and cubic fits have shown that the ENSO index is better fit by the cubic polynomial increasing proportionally to a cubic power of the GLOT variations. The wavelet analysis allowed us to detect the two key periods in the ENSO (ONI) index: 4 - 5 years and 12 years. The smaller period of 4.5 years can be linked to the motion of tectonic plates while the larger period of 12 years is shown to have a noticeable correlation of 25% with frequencies of the underwater (submarine) volcanic eruptions in the areas with ENSO occurrences. Not withholding any local terrestrial factors considered to contribute to the ENSO occurrences, we investigated the possibility of the volcanic eruptions causing ENSO to be also induced by the tidal forces of Jupiter and Sun showing the correlation of the underwater volcanic eruption frequency with the Jupiter-Earth distances to be 12% and with the Sun-Earth distances, induced by the solar inertial motion, in January, when the Earth is turned to the Sun with the southern hemisphere where the ENSO occurs, to become 15%. Hence, the underwater volcanic eruptions induced by tidal forces of Jupiter and Sun can be the essential additional factors imposing this 12 year period of the ENSO (ONI) index variations. 展开更多
关键词 Sun: Magnetic Field Sun: solar activity Sun: Inertial Motion Earth: Temperature Earth: Sea level Earth: Ice Area
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太阳辐射作用下不同活动水平的室内人体传热特性及热舒适研究
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作者 刘国丹 乔美杰 +5 位作者 纪铱行 胡松涛 梁树维 赵一舟 王甫来 丁肇翔 《制冷学报》 CAS CSCD 北大核心 2024年第1期70-78,共9页
太阳辐射是影响室内空调负荷的重要因素,当阳光直射人体时,影响人体与周围环境热交换,进而影响热感觉,人体处于热中性的环境温度的变化关乎空调系统能耗和人体热舒适。本研究在人工气候室进行冬季实验,利用太阳辐射模拟装置控制太阳辐... 太阳辐射是影响室内空调负荷的重要因素,当阳光直射人体时,影响人体与周围环境热交换,进而影响热感觉,人体处于热中性的环境温度的变化关乎空调系统能耗和人体热舒适。本研究在人工气候室进行冬季实验,利用太阳辐射模拟装置控制太阳辐射强度,受试者穿着典型服装,分别进行静坐与两种步速(3.2、5 km/h)活动,测试生理参数并进行热感觉问卷调查,分析太阳辐射与活动水平共同作用下,人体与周围环境间的传热特性,研究热舒适区偏移规律。结果表明:有太阳辐射时,随着活动强度增加,蒸发传热量占比增加,对流传热与辐射传热占比减小,热舒适区向下偏移,冬季人体维持舒适状态所需的环境温度降低。为该条件下空调室内设计参数的设定提供一定参考,使空调系统更节能。 展开更多
关键词 太阳辐射 活动水平 传热特性 热舒适区 热感觉
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Cyclicity related to solar activity in lacustrine organic-rich shales and their significance to shale-oil reservoir formation 被引量:2
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作者 Miruo Lin Kelai Xi +4 位作者 Yingchang Cao Rukai Zhu Xiaobing Niu Honggang Xin Weijiao Ma 《Geoscience Frontiers》 SCIE CAS CSCD 2023年第5期91-107,共17页
The formation mechanism of micron-to centimeter-scale sedimentary cycles in lacustrine shales is a hot topic of research,because these small-scale sedimentary cycles significantly influence shale-oil distribution hete... The formation mechanism of micron-to centimeter-scale sedimentary cycles in lacustrine shales is a hot topic of research,because these small-scale sedimentary cycles significantly influence shale-oil distribution heterogeneity.High-frequency paleoenvironmental evolution is an important controlling factor for the formation of small-scale sedimentary cycles.However,the driving factors of high-frequency paleoenvironmental evolution and the formation process of sedimentary cycles under its constraint remain speculative.In this study,which focuses on lacustrine shales,we find that the alternating deposition of variable thickness of organic-rich lamina(ORL)and silty-grained felsic lamina(SSFL)form sedimentary cycles on the micron to centimeter scale in the Chang 73 sub-member of the Yanchang Formation in the Ordos Basin.Based on detailed petrographic characterization,in-situ geochemical parameter testing,and high-resolution cycle analysis,the formation process of cyclical sedimentary records and related paleoenvironmental evolution are investigated.Three solar activity cycles were identified from the shales,namely the 360–500 yr,81–110 yr,and 30–57 yr cycles(cycles I,II,and III,respectively).Highfrequency paleoenvironmental evolution caused by solar activity induced lake-level fluctuation,which further controlled silty-grained sediment deposition and organic matter preservation in deep lake areas.Cycle I controlled relatively long-term lake-level fluctuation,driving several pairs of SSFL and ORL deposition at the centimeter scale.Cycles II and III were short-term cycles and acted on the millimeter to micrometer scale,further complicating the sedimentary strata forming during the period of lake-level fall induced by cycle I.The cyclic deposition of SSFL and ORL correspond to cycle III.Lake-level fluctuation influenced by cycle II mainly caused SSFL thickness variation in each lamina couplet.During the period of lake-level rise induced by cycle I,periods of lake level rise during cycles II,and III show cyclic varia 展开更多
关键词 Triassic Lacustrine shales solar activity Lake-level fluctuation Shale-oil exploration
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Terrestrial Temperature, Sea Levels and Ice Area Links with Solar Activity and Solar Orbital Motion
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作者 Valentina V. Zharkova Irina Vasilieva 《Natural Science》 2023年第9期233-255,共23页
This paper explores the links between terrestrial temperature, sea levels and ice areas in both hemispheres with solar activity indices expressed through averaged sunspot numbers together with the summary curve of eig... This paper explores the links between terrestrial temperature, sea levels and ice areas in both hemispheres with solar activity indices expressed through averaged sunspot numbers together with the summary curve of eigenvectors of the solar background magnetic field (SBMF) and with changes of Sun-Earth distances caused by solar inertial motion resulting from the gravitation of large planets in the solar system. Using the wavelet analysis of the GLB and HadCRUTS datasets two periods: 21.4 and 36 years in GLB, set and the period of about 19.6 years in the HadCRUTS are discovered. The 21.4-year period is associated with variations in solar activity defined by the summary curve of the largest eigenvectors of the SBMF. A dominant 21.4-year period is also reported in the variations of the sea level, which is linked with the period of 21.4 years detected in the GLB temperature and the summary curve of the SBMF variations. The wavelet analysis of ice and snow areas shows that in the Southern hemisphere, it does not show any links to solar activity periods while in the Northern hemisphere, the ice area reveals a period of 10.7 years equal to a usual solar activity cycle. The TSI in March-August of every year is found to grow with every year following closely the temperature curve, because the Sun moves closer to the Earth orbit owing to gravitation of large planets (solar inertial motion, SIM), while the variations of solar radiation during a whole year have more steady distribution without a sharp TSI increase during the last two centuries. The additional TSI contribution caused by SIM is likely to secure the additional energy input and exchange between the ocean and atmosphere. 展开更多
关键词 Sun: Magnetic Field Sun: solar activity Sun: Inertial Motion Earth: Temperature Earth: Sea level Earth: Ice Area
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中国区域掩星观测与IRI-2016电离层峰值参数的比较 被引量:2
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作者 孙方方 罗佳 +1 位作者 徐晓华 王涵 《武汉大学学报(信息科学版)》 EI CSCD 北大核心 2020年第3期403-410,共8页
对2008—2014年由气象、电离层和气候卫星联合观测系统(Constellation Observing System for Meteorology Ionosphere and Climate,COSMIC)掩星观测与最新版国际电离层参考模型IRI-2016输出得到的电离层峰值参数(峰值密度NmF2与峰值高度... 对2008—2014年由气象、电离层和气候卫星联合观测系统(Constellation Observing System for Meteorology Ionosphere and Climate,COSMIC)掩星观测与最新版国际电离层参考模型IRI-2016输出得到的电离层峰值参数(峰值密度NmF2与峰值高度hmF2)在中国区域进行了比较。IRI-2016模型输出值与COSMIC掩星反演值的相关性在太阳活动高年(2011—2014年)整体上高于太阳活动低年(2008—2010年)。在低年春秋季的当地时间(local time,LT)12:00—14:00,IRI-2016相对于COSMIC掩星在30°N^55°N区域内对NmF2和hmF2分别存在低估和高估现象,在15°N^30°N区域内则恰恰相反。对于NmF2,采用IRI_CCIR和IRI_URSI两种选项的模型输出值在中午时分均存在高估,在低年高估更为显著。对于hmF2,采用IRI_CCIR和IRI_AMTB两种选项的模型输出值在低年各季节均存在高估,且IRI_AMTB选项高估更显著,冬季最突出。结果表明,在中国区域由IRI-2016模型计算NmF2和hmF2时,分别推荐使用IRI_CCIR和IRI_Shubin选项。 展开更多
关键词 COSMIC掩星 IRI-2016模型 峰值参数 太阳活动水平
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HOI延迟对BDS对流层参数估计的影响 被引量:3
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作者 方卓 魏僮 +1 位作者 房海若 张兵良 《大地测量与地球动力学》 CSCD 北大核心 2023年第9期893-898,共6页
基于GAMIT10.71研究高阶电离层(high-order ionosphere, HOI)延迟对于北斗卫星导航系统(BDS) B2I、B2a和B3I三种频段信号对对流层参数估计的影响。实验结果表明,太阳活动低水平时期,HOI延迟对B2I天顶总延迟(zenith total delay, ZTD)、... 基于GAMIT10.71研究高阶电离层(high-order ionosphere, HOI)延迟对于北斗卫星导航系统(BDS) B2I、B2a和B3I三种频段信号对对流层参数估计的影响。实验结果表明,太阳活动低水平时期,HOI延迟对B2I天顶总延迟(zenith total delay, ZTD)、南北梯度(NSgrad)和东西梯度(EWgrad)的影响最大分别达到0.80 mm、0.60 mm和0.99 mm,对B2a的ZTD、NSgrad和EWgrad的影响最大分别达到3.60 mm、10.77 mm和10.74 mm,对B3I的ZTD、NSgrad和EWgrad的影响最大分别达到1.60 mm、3.28 mm和5.90 mm;太阳活动高水平时期,HOI对对流层参数估计产生了更大影响。实验结果进一步表明,HOI对对流层参数估计的影响呈现出白天高于夜晚、低纬度地区高于高纬度地区的特征。 展开更多
关键词 高阶电离层(HOI)延迟 频段信号 太阳活动低水平 太阳活动高水平 对流层参数估计
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基于改进混合高斯模型的太阳Hα图像特征检测
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作者 梁宇峰 白先勇 冯松 《电子科技》 2018年第12期57-62,67,共7页
文中提出将三帧差分与混合高斯模型相结合的算法来对太阳Hα图像中的特征进行检测。对图像进行标准差归一化后,利用维纳滤波方法对图像进行平滑处理;并利用三帧差分快速得到一副背景图像,更新到混合高斯模型主背景分布中建立稳定的动态... 文中提出将三帧差分与混合高斯模型相结合的算法来对太阳Hα图像中的特征进行检测。对图像进行标准差归一化后,利用维纳滤波方法对图像进行平滑处理;并利用三帧差分快速得到一副背景图像,更新到混合高斯模型主背景分布中建立稳定的动态背景,从而探测作为前景变化的耀斑、暗条活动;按照太阳活动面积去除掉前景图像中残留的噪声点完成检测操作;根据检测结果计算太阳活动的相关数据。文中分别选用了国家天文台怀柔太阳观测基地的两组数据和太阳全球振荡监测网的一组数据来展示其执行过程并对结果进行评价。实验结果表明,同目前存在的耀斑识别算法相比,文中算法能够自动识别出暗条和耀斑的爆发;能根据耀斑面积演化计算出耀斑级别和耀斑的开始、峰值和结束时刻;有效解决了噪声与光照变化的影响,提高了耀斑检测的准确度。 展开更多
关键词 太阳活动特征检测 维纳滤波 三帧差分法 混合高斯模型 耀斑等级 暗条识别
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