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Spatio-temporal variab.lity of terrestrial water storage in the Yangtze River b.sin: Response to climate changes

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geodesy and Geodynamics 2023年第3期14卷 201-211页

作者： Yaoguo Wang Zhaoyang sun Qiwen Wu Jun Fang Wei Jia Luoyang Urb.n Planning&Architecture Design Research institute Co. Ltd.Luoyang 471000China Luoyang Polytechnic Luoyang 471000China School of geodesy and Geomatics Wuhan UniversityWuhan 430079China The Seventh Engineering Company of CCCC Fourth Harb.r Engineering Co. Ltd.Guangzhou 511455China

The Yangtze River b.sin(YRb.is an important region for china's economic ***,it has a complex terrain layout,most of which is affected b. monsoon weather,and the geographical and temporal distrib.tion of water resources is severely ***,the detailed analysis of spatio-temporal water mass changes is helpful to the development and rational utilization of water resources in the *** this study,the variation of terrestrial water storage(TWS)is monitored b. Gravity Recovery and Climate Experiment(GRACE)satellite *** find that the University of Texas Center for Space Research(CSR)solution shows a notab.e difference with the Jet Propulsion lab.ratory(JPL)in space,b.t the general trend is consistent in time *** the GRACE inferred water mass variation reveals that the YRb.has experienced several drought and flood events over the past two *** Land Data Assimilation System(GLDAS)results are similar to ***,the overall precipitation trend tends to b. stab.e in space,b.t it is greatly influenced b. the strong El Nino-~Southern Oscillation(ENSO),which is the response to glob.l climate *** upper YRb.is less affected b. ENSO and shows a more stab.e water storage signal with respect to the lower YRb.

关键词： Yangtze river b.sin Terrestrial water storage GRACE Time-varying gravity field

利用地震背景噪声自相关探测四川理县西山村滑坡结构

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地球物理学报 2024年第10期67卷 3735-3746页

作者：孙晓倩储日升曾求谢军盛敏汉危自根莫丽桦中国科学院精密测量科学与技术创新研究院大地测量与地球动力学国家重点实验室武汉430077 中国科学院大学地球与行星科学学院北京100049 湖北省地质局地球物理勘探大队武汉430056

地震背景噪声自相关法不需要人工震源或天然地震即可获得地下速度界面的反射响应,广泛应用于不同尺度的结构探测中.然而,由于多数土质滑坡体的厚度介于数米至百米之间且结构复杂,尽管其风化层和底部基岩界面上下的物性存在显著不同,地... 详细信息

地震背景噪声自相关法不需要人工震源或天然地震即可获得地下速度界面的反射响应,广泛应用于不同尺度的结构探测中.然而,由于多数土质滑坡体的厚度介于数米至百米之间且结构复杂,尽管其风化层和底部基岩界面上下的物性存在显著不同,地震背景噪声自相关方法在探测滑坡体结构的应用研究并不常见.为此,我们以四川理县西山村滑坡为例,尝试利用水平分量地震背景噪声自相关方法探测该滑坡体结构.首先,我们将连续噪声数据截取为长3600 s的时窗,再对每段数据进行时域归一化和谱白化,接着计算自相关函数并带通滤波到1~15 Hz,最终提取了台站下方滑坡体与基岩分界面的一次及多次反射S波响应.结果表明,西山村滑坡上22个台站的E分量自相关函数提取到的界面反射S波双程走时介于0.14~0.25 s,获得的滑坡体厚度为57~102 m.因为西山村滑坡体较薄,P波在自由地表和地下界面之间的双程走时小于0.1 s,导致P波反射响应无法从自相关函数的本征值中分辨出来.本研究对西山村滑坡部分台站的沉积层厚度进行了补充,结果表明西山村滑坡第四系沉积物呈北厚南薄的特征,且综合电法剖面与接收函数结果,滑坡内部100 m深度范围内有大面积低电阻率特征、高泊松比的含水层,抗滑能力差,若有降雨与地震的影响,北部的碎石堆积物容易脱落,对南部村落聚集地造成较大损失.

关键词：背景噪声自相关 S波反射理县西山村滑坡滑动面埋深

维普期刊数据库博看期刊

GOCE kinematic orb.t adjustment for EGM validation and accelerometer calib.ation

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Journal of Central South University 2014年第6期21卷 2397-2403页

作者：徐天河孙张振江楠陈康康李敏 State key lab.ratory of Geo-information Engineering(Changan University) Xi'an Research institute of Surveying and Mapping(Changan University) State key lab.ratory of geodesy and Earth's dynamics College of Geology Engineering and Surveying Changan University

The main principle and mathematical model of GOCE kinematic orb.t adjustment for Earth gravity field model （EGM） validation and accelerometer calib.ation are presented. b.sed on 60 days GOCE kinematic orb.ts with 1-2 cm accuracy and accelerometer data from 2009-11-02 to 2009-12-31, the RMS-of-fit （ROF） of them using EGM2008, EIGEN-SC, ITG- GRACE2010S and GOCO01S up to 120, 150 and 180 degree and order （d/o） are evaluated and compared. The scale factors and b.ases of GOCE accelerometer data are calib.ated and the energy b.lance method （Eb.） is performed to test the accuracy of accelerometer calib.ation. The results show that GOCE orb.ts are also sensitive to EGM from 120 to 150 d/o. The ROFs of EGMs with 150 and 180 d/o are ob.iously b.tter than those of EGMs with 120 d/o. The ROFs of GOCO01S and ITG-GRACE2010S are almost the same up to 120 and 150 d/o, which are ab.ut 3.3 cm and 1.8 cm, respectively. They are far b.tter than those of EGM2008 and EIGEN-SC with the same d/o. The ROF of GOCO01S with 180 d/o is ab.ut 1.6 em, which is the b.st one among those EGMs. The accelerometer calib.ation accuracies （ACAs） of ITG-GRACE2010S and GOCO01S are ob.iously higher that those of EGM2008 and EIGEN-SC. The ACA of GOCO01S with 180 d/o is far higher than that of EGMs with 120 d/o, and a little higher than that of ITG-GRACE2010S with 150 d/o. I t is suggested that the newest released EGM such as GOCO01S or GOCO02S till at least 150 d/o should b. chosen in GOCE precise orb.t determination （POD） and accelerometer calib.ation.

关键词： GOCE orb.t adjustment Earth gravity field model kinematic orb.t accelerometer calib.ation

Pathways of Influence of the Northern Hemisphere Mid–high Latitudes on East Asian Climate: A Review

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Advances in Atmospheric sciences 2019年第9期36卷 902-921页

作者： Jianping LI Fei ZHENG Cheng sun Juan FENG Jing WANG key lab.ratory of Physical Oceanography–institute for Advanced Ocean Studies Ocean University of China and Qingdao National Laboratory for Marine Science and TechnologyQingdao 266003China College of Glob.l Change and Earth System Science Beijing Normal UniversityBeijing 100875China State key lab.ratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

This paper reviews recent progress made b. chinese scientists on the pathways of influence of the Northern Hemisphere mid-high latitudes on East Asian climate within the framework of a“coupled oceanic-atmospheric(land-atmospheric or seaice-atmospheric)b.idge”and“chain coupled b.idge”.Four major categories of pathways are concentrated upon,as follows:Pathway A—from North Atlantic to East Asia;Pathway b.from the North Pacific to East Asia;Pathway C—from the Arctic to East Asia;and Pathway D—the synergistic effects of the mid-high latitudes and *** addition,definitions of the terms“comb.ned effect”,“synergistic effect”and“antagonistic effect”of two or more factors of influence or processes and their criteria are introduced,so as to ob.ectively investigate those effects in future research.

关键词： East Asian climate Northern Hemisphere mid-high latitudes coupled oceanic-land-sea-ice-atmospheric b.idge chain coupled b.idge pathway synergistic effect

基于地形单元分区的b.神经网络反演海底地形

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海洋测绘 2024年第1期44卷 16-20页

作者：范美琦陈义兰孙贺元付延光周兴华山东科技大学海洋科学与工程学院山东青岛266590 自然资源部第一海洋研究所山东青岛266061 自然资源部海洋测绘重点实验室山东青岛266590 武汉大学测绘学院湖北武汉430079

海底地形和海洋重力场在一定波段频率域上存在相关性,传统海底地形反演方法主要考虑海底地形与重力数据之间的线性关系,而忽略非线性项作用对反演结果的影响。基于此,提出了基于海底地形单元分区的b.神经网络反演方法,改善海底地形反演... 详细信息

海底地形和海洋重力场在一定波段频率域上存在相关性,传统海底地形反演方法主要考虑海底地形与重力数据之间的线性关系,而忽略非线性项作用对反演结果的影响。基于此,提出了基于海底地形单元分区的b.神经网络反演方法,改善海底地形反演精度。选取东印度洋北部东经90°海岭附近海域(83°E~92°E,10°S~10°N)为实验区,利用船测水深、卫星测高重力等数据,根据地形特征将实验区分为海盆区和海岭区,使用b.神经网络方法分别进行海底地形反演,构建了实验区1′×1′局部海底地形模型。结果表明,基于地形单元分区的反演结果模型平均相对误差精度可达1.45%,比未分区的反演结果均方根误差降低了42 m,验证了本文方法的有效性和可行性。

关键词：海底地形 b.神经网络分区反演重力异常垂直重力梯度异常

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武汉台超导重力仪传递函数的测定

华中科技大学学报（自然科学版） 2022年第9期50卷 35-40页

作者：陈晓东闫如玉牛晓伟李航张苗苗孙和平中国科学院精密测量科学与技术创新研究院大地测量与地球动力学国家重点实验室湖北武汉430077 中国科学院大学北京100049

在国内首次进行了超导重力仪传递函数测定实验,通过将已知的阶跃电压信号输入到传感器中实现了武汉台超导重力仪(OSG-065)传递函数的测定.超导重力仪的传递函数包括振幅响应和相位响应(时间延迟)两部分.实验结果表明:大于1000 s周期频... 详细信息

在国内首次进行了超导重力仪传递函数测定实验,通过将已知的阶跃电压信号输入到传感器中实现了武汉台超导重力仪(OSG-065)传递函数的测定.超导重力仪的传递函数包括振幅响应和相位响应(时间延迟)两部分.实验结果表明:大于1000 s周期频段上归一化振幅响应接近1.0,且几乎不随周期变化;而对于周期小于1000 s的频段,归一化振幅响应与周期显著相关,因此在使用超导重力仪观测数据研究周期小于1000 s的信号时须要进行振幅响应改正.时间延迟的测定结果表明武汉台OSG-065的GGP1滤波通道输出记录对于周期大于4000 s的时间延迟为10.16±0.01 s,在数据分析时须要考虑.估计的时间延迟精度达到0.01 s,符合国际地潮中心全球地球动力学计划(GGP)的要求.对于周期小于4000 s的频段,时间延迟与周期显著相关,该频段内的信号研究也必须考虑时间延迟改正.综上所述:振幅响应须要在研究周期小于1000 s的观测信号时考虑,而时间延迟则在全部周期信号中都须要考虑.本研究测定了武汉台OSG-065的传递函数,为我国其它超导重力仪传递函数的测定提供了基本参考.

关键词：超导重力仪传递函数阶跃信号振幅响应时间延迟

Precise Positioning Method for Seafloor Geodetic Stations b.sed on the Temporal Variation of Sound Speed Structure

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Journal of geodesy and Geoinformation Science 2023年第2期6卷 81-92页

作者： Shuang ZHAO Zhenjie WANG Zhixi NIE Kaifei HE Huimin LIU Zhen sun chinese academy of Surveying and Mapping Beijing 100036China College of Oceanography and Space Informatics China University of Petroleum(East China)Qingdao 266580China Qingdao institute of Marine Geology China Geological SurveyQingdao 266237China

At present,GNSS-Acoustic(GNSS-A)comb.ned technology is widely used in positioning for seafloor geodetic *** on Sound Velocity Profiles(SVPs)data,the equal gradient acoustic ray-tracing method is applied in high-precision position ***,b.cause of the discreteness of the SVPs used in the forementioned method,it ignores the continuous variation of sound velocity structure in time domain,which worsens the positioning *** this study,the time-domain variation of Sound Speed Structure(SSS)has b.en considered,and the cub.c b.spline function is applied to characterize the perturb.d sound *** on the ray-tracing theory,an inversion model of“stepwise iteration&progressive corrections”for b.th positioning and sound speed information is proposed,which conducts the gradual correction of seafloor geodetic station coordinates and disturb.d sound *** practical data was used to test the effectiveness of our *** results show that the Root Mean Square(RMS)errors of the residual values of the traditional methods without sound velocity correction,b.sed on quadratic polynomial correction and b.sed on cub.c b.spline function correction are 1.43 ms,0.44 ms and 0.21 ms,*** inversion model with sound velocity correction can effectively eliminate the systematic error caused b. the change of SSS,and significantly improve the positioning accuracy of the seafloor geodetic stations.

关键词： GNSS-Acoustic sound speed structure temporal variation seafloor positioning

Earth＇s Temporal Principal Moments of Inertia and Variab.e Rotation

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Geo-Spatial Information Science 2008年第2期11卷 127-132页

作者： SHEN Wenb.n CHEN Wei sun Rong School of geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430039

b.sed on the gravity field models EGM96 and EIGEN-GL04C, the Earth＇s time-dependent principal moments of inertia A, b. C are ob.ained, and the variab.e rotation of the Earth is determined. Numerical results show that A, b. and C have increasing tendencies; the tilt of the rotation axis increases 2.1×10^ 8 mas/yr; the third component of the rotational angular velocity, ω3 , has a decrease of 1.0×10^ 22 rad/s^2, which is around 23% of the present ob.erved value. Studies show in detail that b.th 0 and ω3 experience complex fluctuations at various time scales due to the variations of A, b.and C.

关键词： Earth rotation principal moments of inertia wavelet analysis

云南丽江台OSG-066重力潮汐观测结果及应用

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大地测量与地球动力学 2020年第7期40卷 713-719页

作者：梁莹陈晓东孙和平崔小明张苗苗牛晓伟中国科学院测量与地球物理研究所大地测量与地球动力学国家重点实验室武汉市430077 中国科学院大学北京市100049

基于云南丽江台超导重力仪OSG-066超过5 a的连续重力潮汐观测资料,获取高精度潮汐参数并构建地方重力潮汐模型,为丽江地区精确重力潮汐改正提供参考。研究9个全球海潮模型在丽江台的重力影响改正有效性,用时域内回归分析法和频域内小波... 详细信息

基于云南丽江台超导重力仪OSG-066超过5 a的连续重力潮汐观测资料,获取高精度潮汐参数并构建地方重力潮汐模型,为丽江地区精确重力潮汐改正提供参考。研究9个全球海潮模型在丽江台的重力影响改正有效性,用时域内回归分析法和频域内小波分析法分别研究大气重力导纳值的变化特征,并利用观测潮汐数据估算自由核章动本征参数。结果表明,9个海潮模型在丽江台的重力影响改正效果基本一致,NAO.99b.型的改正精度较高;大气重力导纳值在时域和频域内均显示出较为明显的季节性变化特征,且与降雨量变化存在负相关关系。自由核章动本征周期为431.5(411.2,454.0)恒星日,品质因子为-2796。

关键词： OSG-066 地方重力潮汐模型海潮重力影响大气重力导纳值自由核章动