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Spatial and temporal patterns of the inter-annual oscillations of glacier mass over Central Asia inferred from Gravity Recovery and Climate Experiment(GRACE) data

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Journal of Arid Land 2017年第1期9卷 87-97页

作者： ZHU Chuandong lu yang SHI Hongling {2. {3. State Key Laboratory of geodesy and Earth's Dynamics Chinese Academy of Sciences Wuhan 430077 China University of Chinese academy of sciences Beijing 100049 China Center for Space Research University of Texas at Austin Austin 78759 USA

Monitoring glacier mass balance is crucial to managing water resources and also to understanding climate change for the arid and semi-arid regions of Central Asia. This study extracted the inter-annual oscillations of glacier mass over Central Asia from the first ten principal components（S-PCs） of filtered variability via multichannel singular spectral analysis（MSSA）, based on gridded data of glacier mass inferred from Gravity Recovery and Climate Experiment（GRACE） data obtained from July 2.02.to March 2.15. Two significant cycles of glacier mass balance oscillations were identified. The first cycle with a period of 6.1-year accounted for 54.5% of the total variance and the second with a period of 2.3.year accounted for 4.3.. The 6.1-year oscillation exhibited a stronger variability compared with the 2.3.year oscillation. For the 6.1-year oscillation, the results from lagged cross-correlation function suggested that there were significant correlations between glacier mass balances and precipitation variations with the precipitation variations leading the response of glacier mass balances by 9–16 months.

关键词： Gravity Recovery and Climate Experiment glacier mass balance multichannel singular spectral analysis Central Asia

Characterizing three-dimensional features of Antarctic subglacial lakes from the inversion of hydraulic potential——Lake Vostok as a case study

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Advances in Polar Science 2019年第1期30卷 70-75页

作者： LI Yan lu yang {2. {3. SHI Hongling XI Hui State Key Laboratory of geodesy and Earth's Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences University of Chinese academy of sciences

To estimate basal water storage beneath the Antarctic ice sheet, it is essential to have data on the three-dimensional characteristics of subglacial lakes. We present a method to estimate the water depth and surface area of Antarctic subglacial lakes from the inversion of hydraulic potential method. Lake Vostok is chosen as a case study because of the diverse and comprehensive measurements that have been obtained over and around the lake. The average depth of Lake Vostok is around 3.5±4 m. We estimated the surface area of Lake Vostok beneath the ice sheet to be about 13.00±594 km^2. The lake consists of two sub-basins separated by a ridge at water depths of about 2.0–3.0 m. The surface area of the northern sub-basin is estimated to be about half of that of the southern basin. The maximum depths of the northern and southern sub-basins are estimated to be about 450 and 850 m, respectively. Total water volume is estimated to be about 4658±2.4 km^3. These estimates are compared with previous estimates obtained from seismic data and inversion of aerogravity data. In general, our estimates are closer to those obtained from the inversion of aerogravity data than those from seismic data, indicating the applicability of our method to the estimation of water depths of other subglacial lakes.

关键词： three-dimensional features Lake Vostok hydraulic potential subglacial water storage

不同类型地震震级与重力变化异常的统计特征及其机理分析

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地球物理学报 2024年第8期67卷 3032-3059页

作者：李树鹏胡敏章祝意青朱成林崔华伟陆汉鹏张刚王锋吉山东省地震局济南250014 中国地震局地震研究所地震大地测量重点实验室武汉430071 武汉引力与固体潮国家野外科学观测研究站武汉430071 中国地震局第二监测中心西安710054

依据收集到的107个4.0级以上地震震例,研究中国陆区中强地震震前重力变化异常统计特征,探讨地震震级与震前重力变化异常各要素及地震性质之间的统计关系,给出了5、6、7、8级地震震级判定的重力变化异常时变距S、量级G和时间T参考指标,... 详细信息

依据收集到的107个4.0级以上地震震例,研究中国陆区中强地震震前重力变化异常统计特征,探讨地震震级与震前重力变化异常各要素及地震性质之间的统计关系,给出了5、6、7、8级地震震级判定的重力变化异常时变距S、量级G和时间T参考指标,并对比、分析了逆冲型、走滑型和正断型地震的重力变化特点,进而结合流体物质运移假说及岩石物理实验结果,探讨了震前重力变化异常的物理机制,以及其与亚失稳阶段、地震孕育能量的联系.得到的主要结论有:(1)震前重力变化异常参量与震级之间更符合非线性关系,5、6、7、8级地震的震前重力变化异常时变距参考指标分别为67、111、185、3.5 km,重力变化异常量级参考指标分别为49、67、92.12.μGal,重力变化异常时间参考指标分别为1.6、2.5、3.7、5.2.a.(2.地震类型对震前重力变化参量有一定影响,尤其是7级以上强震的差异更加明显,逆冲型地震的重力变化量级及时变距可能更大;重力变化异常时间方面,正断型地震可能对应更长的重力变化时间,逆冲型次之,走滑型最短.(3.震前重力变化异常的物理机制可能是,在孕震晚期、亚失稳阶段,震中周边区域岩石裂隙增多、扩展、贯通,引起流变性的深部幔源物质向地壳运移,同时地壳内先存的流体物质由于应力分布不均而大规模迁移,最终在地表引起重力场变化响应.(4)目前流动重力观测受到时空密度的制约,地震预报主要针对5级以上地震,且震级越大预报效能越好.

关键词：地震预报重力变化异常震级震源机制解

同方期刊数据库博看期刊评论

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海面重力异常向下延拓的两种方法

大地测量与地球动力学 2007年第4期27卷 77-81页

作者：郭树松张子占陆洋中国科学院测量与地球物理研究所

针对空间重力异常向下延拓方法不适用于海面重力异常向下延拓的问题,根据珀雷原理求地球表层内部重力的方法、海水密度及海底地形的特征,提出了两种海面重力异常向下延拓的算法。数值实验结果验证了新方法的有效性。

关键词：海面重力异常重力异常垂直梯度向下延拓圆柱法几何法

Latest Progress of the Chinese Meteorological Satellite Program and Core Data Processing Technologies

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Advances in Atmospheric sciences 2019年第9期36卷 1027-1045页

作者： Peng zhang Qifeng lu Xiuqing HU Songyan GU Lei {2. Min MIN Lin CHEN Na XU Ling Sun Wenguang BAI Gang MA Di XIAN Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites National Satellite Meteorological CenterChina Meteorological Administration

In this paper,the latest progress,major achievements and future plans of Chinese meteorological satellites and the core data processing techniques are ***,the latest three FengYun(FY)meteorological satellites(FY-2.,FY-3.,and FY-4A)and their primary objectives are introduced Second,the core image navigation techniques and accuracies of the FY meteorological satellites are elaborated,including the latest geostationary(FY-2.4)and polar-orbit(FY-3.***,the radiometric calibration techniques and accuracies of reflective solar bands,thermal infrared bands,and passive microwave bands for FY meteorological satellites are *** also illustrates the latest progress of real-time calibration with the onboard calibration system and validation with different methods,including the vicarious China radiance calibration site calibration,pseudo invariant calibration site calibration,deep convective clouds calibration,and lunar ***,recent progress of meteorological satellite data assimilation applications and quantitative science produce are summarized at *** main progress is in meteorological satellite data assimilation by using microwave and hyper-spectral infrared sensors in global and regional numerical weather prediction ***,the latest progress in radiative transfer,absorption and scattering calculations for satellite remote sensing is summarized,and some important research using a new radiative transfer model are illustrated.

关键词： meteorological satellite geolocation calibration and validation satellite data assimilation radiative transfer model

基于GRACE RL06数据监测和分析南极冰盖2.个流域质量变化

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地球物理学报 2019年第3期62卷 864-882页

作者：高春春陆洋史红岭张子占徐长仪谭冰南阳师范学院河南南阳473061 "中央"研究院地球科学研究所中国台北11529 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430077 中国科学院大学北京100049 中国地震局地震预测研究所北京100036

本文基于CSR最新公布的GRACE RL06版本数据,采用Slepian空域反演法估算了南极冰盖2.个流域的质量变化.Slepian空域反演法结合了Slepian空间谱集中法和空域反演法的技术优势,能够有效降低GRACE在小区域反演时信号出现的严重泄漏和衰减,... 详细信息

本文基于CSR最新公布的GRACE RL06版本数据,采用Slepian空域反演法估算了南极冰盖2.个流域的质量变化.Slepian空域反演法结合了Slepian空间谱集中法和空域反演法的技术优势,能够有效降低GRACE在小区域反演时信号出现的严重泄漏和衰减,进而精确获得南极冰盖在每个流域的质量变化.相对于GRACE RL05版本数据,RL06在条带误差的控制上要更加优化,获得的南极冰盖质量变化时间序列也更加平滑,但在趋势估算上差别并不明显(小于10Gt/a).本文的估算结果显示:在2.02.4月至2.16年8月期间,整个南极冰盖质量变化速率为-118.6±16.3.t/a,其中西南极为-142.4±10.5Gt/a,南极半岛为-2..2.2.1Gt/a,东南极则为52.9±8.6Gt/a.南极冰盖损失最大的区域集中在西南极Amundsen Sea Embayment(流域2.-2.),该地区质量变化速率为-2.3.5±4.1Gt/a,其次为南极半岛(流域2.-2.)以及东南极Victoria-Wilkes Land (流域13.1.),质量变化速率分别为-2..2.2.1Gt/a和-19.0±4.7Gt/a,其中Amundsen Sea Embayment和南极半岛南部两个地区的冰排放呈现加速状态.南极冰盖质量显著增加的区域主要有西南极的Ellsworth Land(流域1)和Siple Coast(流域18和19)以及东南极的Coats-Queen Maud-Enderby Land (流域3.8),三个地区质量变化速率分别为17.2.2.4Gt/a、43.9±1.9Gt/a和62.7±3.8Gt/a,质量增加大多来自降雪累积,比如:Coats-Queen Maud-Enderby Land在2.09年和2.11年发生的大规模降雪事件,但也有来自冰川的增厚,如:Siple Coast地区Kamb冰流的持续加厚.此外,对GRACE估算的南极冰盖质量变化年际信号进行初步分析发现,GRACE年际信号与气候模型估算的冰盖表面质量平衡年际信号存在显著的线性相关关系,但与主要影响南极气候年际变化的气候事件之间却不存在线性相关关系,这说明南极冰盖质量变化的年际信号主要受冰盖表面质量平衡的支配,而气候事件对冰盖表面质量平衡的影响可能是复杂的非线性耦合过程.

关键词：南极冰盖质量平衡 GRACE 流域年际变化

利用GRACE监测全球海水质量变化时滤波处理的影响分析

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大地测量与地球动力学 2016年第5期36卷 380-385页

作者：郗慧张子占陆洋高春春朱传东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徐东大街340号430077 中国科学院大学北京市玉泉路甲19号100049 德克萨斯大学奥斯汀分校空间研究中心南阳师范学院环境科学与旅游学院南阳市卧龙路1638号473061

利用CSR公布的GRACE RL05月重力场数据,采用多种滤波方法推算全球平均海水质量变化,并与GFZ公布的已滤波数据DDK1～DDK5估算结果进行比较。结果表明,不同的滤波方法对估算全球平均海水质量变化结果的影响是显著的,主要体现在信号的空间... 详细信息

利用CSR公布的GRACE RL05月重力场数据,采用多种滤波方法推算全球平均海水质量变化,并与GFZ公布的已滤波数据DDK1～DDK5估算结果进行比较。结果表明,不同的滤波方法对估算全球平均海水质量变化结果的影响是显著的,主要体现在信号的空间分布、时间序列以及拟合的趋势项3.方面。2.02.2.14年CSR RL05数据多种滤波估算的全球海水质量变化速率为1.17～1.2.mm/a,GFZ DDK数据显示的速率为1.2.～1.45mm/a,两组数据给出的加速度项分别为0.1mm/a2.0.07mm/a2.

关键词： GRACE 海水质量变化滤波方法时间序列

Analysis and selection of global marine gravity/gravity gradient aided navigation matching areas

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Analysis and selection of global marine gravity/gravity grad...

基于MIKE2.和灰色模式识别模型的洪湖水质模拟与评价

第九届中国卫星导航学术年会

作者： Lin Wu Hubiao Wang Hua Chai lu zhang Houtse Hsu Yong Wang State Key Laboratory of geodesy and Earth’s Dynamics Institute of Geodesy and GeophysicsChinese Academy of Sciences University of Chinese academy of sciences

With the development of underwater passive navigation in recent years,gravity or gravity gradient matching navigation are utilized to correct the accumulated navigation errors of inertial navigation *** accuracy and success rate of gravity/gravity gradient matching navigation are seriously affected by the features of gravity changes in the sailing *** this paper,a parameter named average gravity difference(AGD) was introduced here to express the level of gravity changes in a certain *** the overall survey of global marine gravity,the AGD values of local areas were calculated and *** a series of experiments,the relationship of AGD values and navigation accuracy in local areas can be generally *** the criterion of selection of matching areas was induced,marine gravity matching areas for navigation can be *** results showed that,take gravity as an example,the AGD values can range from about 0.6 to {3.7 m Gal/nautical mile(1 nautical mile = 1 n mile = 185{3.m) in different areas of the oceans around the *** present technologies,gravity matching navigation could achieve an accuracy of 0.5 n miles in matching areas which have AGD values larger than {3.0 m Gal/n *** this criterion,South China Sea,North Indian Ocean and some other areas can be *** these areas,better navigation results can be obtained since they have rougher gravity *** results would be significant for the development of gravity aided navigation technologies and the construction of underwater PNT system.

关键词： gravity aided navigation matching areas selection underwater navigation gravity matching gravity gradient

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长江流域资源与环境 2018年第9期27卷 2090-2100页

作者：张婷王学雷耿军军班璇杨超吕晓蓉湖北科技学院资源环境科学与工程学院湖北咸宁437100 中国科学院测量与地球物理研究所环境与灾害评估湖北省重点实验室湖北武汉430077 武汉大学资源与环境科学学院湖北武汉430072

认识自然和人为因素驱动下湖泊水环境质量的响应和变化规律,有利于更精确地进行湖泊水质模拟和评价。运用二维水质模型和灰色模式识别模型评价了不同污染源削减方案对洪湖水质的影响。基于2.12.实测地形、水文、气象、水质和污染源定... 详细信息

认识自然和人为因素驱动下湖泊水环境质量的响应和变化规律,有利于更精确地进行湖泊水质模拟和评价。运用二维水质模型和灰色模式识别模型评价了不同污染源削减方案对洪湖水质的影响。基于2.12.实测地形、水文、气象、水质和污染源定量输入,建立了洪湖二维水动力和水质耦合模型。模拟结果显示:水位率定和验证的均方根误差分别为0. 10和0. 08 m,总氮、总磷、铵态氮和高锰酸盐指数的率定误差分别为0. 171、0. 009、0. 110和0. 62. mg/L,验证误差分别为0. 191、0. 02.、0. 079和0. 689 mg/L,水动力模型和水质模型的模拟结果满足精度要求。不同管理措施方案下洪湖水质的恢复效果比较显示,洪湖蓝田和下新河入水口各污染物指标浓度减少50%方案下,水质的恢复效果最好,全湖总氮、总磷、铵态氮和高锰酸盐指数均值减少率分别为3.. 2.、3.. 1%、3.. 3.和2.. 3.,全湖Ⅴ类水质水域基本不存在,全湖90%的区域水体水质综合等级达到Ⅲ类。影响洪湖水质恶化的驱动因子中,关键因素是径流入湖所携带的四湖流域上游地区的非点源污染物。应大力控制上游地区的非点源污染,积极开展洪湖东北部和西北部的湿地水生植被生态修复工程,恢复水体的截污和自净能力。

关键词：水质模拟 MIKE 2. 灰色模式识别模型水质评价洪湖