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Geodesy and Geodynamics 2024年第4期15卷 404-418页

作者： Alireza A.Ardalan Asiyeh Hashemifaraz School of surveying and Geospatial Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

This research aims to optimize the utilization of long-term sea level data from the TOPEX/Poseidon,Jason1,Jason2,and Jason3 altimetry missions for tidal *** generate a time series of along-track observations and apply a developed method to produce tidal models with specific tidal constituents for each *** tidal modeling methodology follows an iterative process:partitioning sea surface height(SSH)observations into analysis/training and prediction/validation parts and ultimately identi-fying the set of tidal constituents that provide the best predictions at each time series *** study focuses on developing 1256 time series along the altimetry tracks over the Baltic Sea,each with its own set of tidal *** of the developed tidal models against the sSH observations within the prediction/validation part reveals mean absolute error(MAE)values ranging from 0.0334 m to 0.1349 m,with an average MAE of 0.089 *** same validation process is conducted on the FES2014 and EOT20 global tidal models,demonstrating that our tidal model,referred to as BT23(short for Baltic Tide 2023),outperforms both models with an average MAE improvement of 0.0417 m and 0.0346 m,*** addition to providing details on the development of the time series and the tidal modeling procedure,we offer the 1256 along-track time series and their associated tidal models as supplementary *** encourage the satellite altimetry community to utilize these resources for further research and applications.

关键词： Satellitealtimetry Baltic Sea Ocean tide modeling Jason3 Jason2 Jason1 TOPEX/Poseidon EOT20 FES2014

Evolution mechanism and treatment timing of penetrating fissures

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Journal of Mountain Science 2024年第10期21卷 3453-3473页

作者： ZHANG Yanjun YAN Yueguan ZHU Yuanhao DAI Huayang college of Geoscience and surveying Engineering China University of Mining and Technology-BeijingBeijing 100083China

The Inner Mongolia mining area in western China are characterized by the development of numerous penetrating fissures,resulting in severe land *** is significant to reveal the underlying evolution mechanism and identify treatment timing for restoring the ecological *** Guanbanwusu mining subsidence area in Inner Mongolia,China was selected as the research case for this *** evolution mechanism of different penetrating fissures was revealed by field measurement,physical simulation and theoretical *** treatment timing prediction model for the mining subsidence area was established based on the enhanced Weibull time *** results show that the ground fissures are mainly step-type and collapse-type *** breaking form of overlying strata determines their vertical opening and horizontal *** high mining intensity in the western mining area results in a shortened period of dynamic fissure expansion and reduced closure *** damage extent of the overlying strata exhibits zoning characteristics both vertically and *** relative standard deviation of the prediction model is only 3.7%.Concurrently,the prediction model is employed to determine the optimal timing for treatment in the study area,estimated to be 259 ***,once this threshold is reached,the study area undergoes treatment and restoration of its e cological *** study addresses the knowledge gap in this field by highlighting the interconnectedness between rock strata structure and evolution mechanism of penetrating fissures,thereby providing a method for determining the treatment timing in mining subsidence areas.

关键词： Mining subsidence Ecological restoration Fissures Evolution mechanism Prediction model Treatment timing

Assessment of the three representative empirical models for zenith tropospheric delay(ZTD)using the CMONOC data

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Geodesy and Geodynamics 2024年第5期15卷 488-494页

作者： Debao Yuan Jian Li Yifan Yao Fei Yang Yingying Wang Ran Chen Tairan Xu college of Geoscience and surveying Engineering China University of Mining and Technology-BeijingBeijing100083China Hubei Luojia Laboratory Wuhan430079China

The precise correction of atmospheric zenith tropospheric delay(ZTD)is significant for the Global Navigation Satellite System(GNSS)performance regarding positioning accuracy and convergence *** the past decades,many empirical ZTD models based on whether the gridded or scattered ZTD products have been proposed and widely used in the GNSS positioning *** there is no comprehensive evaluation of these models for the whole China region,which features complicated topography and *** this study,we completely assess the typical empirical models,the IGGtropSH model(gridded,non-meteorology),the SHAtropE model(scattered,non-meteorology),and the GPT3 model(gridded,meteorology)using the Crustal Movement Observation Network of China(CMONOC)*** general,the results show that the three models share consistent performance with RMSE/bias of 37.45/1.63,37.13/2.20,and 38.27/1.34 mm for the GPT3,SHAtropE and IGGtropSH model,***,the models had a distinct performance regarding geographical distribution,elevation,seasonal variations,and daily *** the southeastern region of China,RMSE values are around 50 mm,which are much higher than that in the western region,approximately 20 *** SHAtropE model exhibits better performance for areas with large variations in *** GPT3 model and the IGGtropSH model are more stable across different months,and the SHAtropE model based on the GNSS data exhibits superior performance across various UTC epochs.

关键词： GNSS Zenith tropospheric delay Empirical ZTD model CMONOC data

Influence of vapor pressure deficit on vegetation growth in China

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Journal of Arid Land 2024年第6期16卷 779-797页

作者： LI Chuanhua ZHANG Liang WANG Hongjie PENG Lixiao YIN Peng MIAO Peidong college of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China Hebei First surveying and Mapping Institute Shijiazhuang 050000China

Vapor pressure deficit(VPD)plays a crucial role in determining plant physiological functions and exerts a substantial influence on vegetation,second only to carbon dioxide(CO_(2)).As a robust indicator of atmospheric water demand,VPD has implications for global water resources,and its significance extends to the structure and functioning of ***,the influence of VPD on vegetation growth under climate change remains unclear in *** study employed empirical equations to estimate the VPD in China from 2000 to 2020 based on meteorological reanalysis data of the Climatic Research Unit(CRU)Time-Series version 4.06(TS4.06)and European Centre for Medium-Range Weather Forecasts(ECMWF)Reanalysis 5(ERA-5).Vegetation growth status was characterized using three vegetation indices,namely gross primary productivity(GPP),leaf area index(LAI),and near-infrared reflectance of vegetation(NIRv).The spatiotemporal dynamics of VPD and vegetation indices were analyzed using the Theil-Sen median trend analysis and Mann-Kendall ***,the influence of VPD on vegetation growth and its relative contribution were assessed using a multiple linear regression *** results indicated an overall negative correlation between VPD and vegetation *** VPD intervals for the correlations between VPD and vegetation indices were identified:a significant positive correlation at VPD below 4.820 hPa,a significant negative correlation at VPD within 4.820–9.000 hPa,and a notable weakening of negative correlation at VPD above 9.000 *** exhibited a pronounced negative impact on vegetation growth,surpassing those of temperature,precipitation,and solar radiation in absolute ***_(2) contributed most positively to vegetation growth,with VPD offsetting approximately 30.00%of the positive effect of CO_(2).As the rise of VPD decelerated,its relative contribution to vegetation growth ***,the intensification of spatial variations in temperature an

关键词： vapor pressure deficit(VPD) near-infrared reflectance of vegetation(NIRv) leaf area index(LAI) gross primary productivity(GPP) Climatic Research Unit(CRU)Time-Series version 4.06(TS4.06) European Centre for Medium-Range Weather Forecasts(ECMWF)Reanalysis 5(ERA-5) climate change

Geochemistry and origins of hydrogen-containing natural gases in deep Songliao Basin,China:Insights from continental scientific drilling

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Petroleum Science 2024年第2期21卷 741-751页

作者： Shuang-Biao Han Chao-Han Xiang Xin Du Lin-Feng Xie Jie Huang Cheng-Shan Wang college of Geoscience and surveying Engineering China University of Mining and TechnologyBeijing100083China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing100083China

The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen *** gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been *** on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different *** gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary *** increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to *** origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and *** shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic ***,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived *** discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas.

关键词： Gas compositions Stable isotopes Gas origins Hydrogen gas Songliao Basin

Urban growth scenario projection using heuristic cellular automata in arid areas considering the drought impact

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Journal of Arid Land 2024年第4期16卷 580-601页

作者： TANG Xiaoyan FENG Yongjiu LEI Zhenkun CHEN Shurui WANG Jiafeng WANG Rong TANG Panli WANG Mian JIN Yanmin TONG Xiaohua college of surveying&Geo-Informatics Tongji UniversityShanghai 200092China Shanghai Key Laboratory of Space Mapping and Remote Sensing for Planetary Exploration Tongji UniversityShanghai 200092China

Arid areas with low precipitation and sparse vegetation typically yield compact urban pattern,and drought directly impacts urban site selection,growth processes,and future *** simulation and projection based on cellular automata(CA)models is important to achieve sustainable urban development in arid *** developed a new CA model using bat algorithm(BA)named bat algorithm-probability-of-occurrence-cellular automata(BA-POO-CA)model by considering drought constraint to accurately delineate urban growth patterns and project future scenarios of Urumqi City and its surrounding areas,located in Xinjiang Uygur Autonomous Region,*** calibrated the BA-POO-CA model for the drought-prone study area with 2000 and 2010 data and validated the model with 2010 and 2020 data,and finally projected its urban scenarios in *** results showed that BA-POO-CA model yielded overall accuracy of 97.70%and figure-of-merits(FOMs)of 35.50%in 2010,and 97.70%and 26.70%in 2020,*** inclusion of drought intensity factor improved the performance of BA-POO-CA model in terms of FOMs,with increases of 5.50%in 2010 and 7.90%in 2020 than the model excluding drought intensity *** suggested that the urban growth of Urumqi City was affected by drought,and therefore taking drought intensity factor into account would contribute to simulation *** BA-POO-CA model including drought intensity factor was used to project two possible scenarios(i.e.,business-as-usual(BAU)scenario and ecological scenario)in *** the BAU scenario,the urban growth dominated mainly in urban fringe areas,especially in the northern part of Toutunhe District,Xinshi District,and Midong *** exceptional and extreme drought areas as a spatial constraint,the urban growth was mainly concentrated in the"main urban areas-Changji-Hutubi"corridor urban pattern in the ecological *** results of this research can help to adjust urban planning and development *** mode

关键词： bat algorithm cellular automata(CA) probability-of-occurrence drought intensity algorithm-probability-of-occurrence-cellular automata(BA-POO-CA)model arid areas

Predicting bathymetry based on vertical gravity gradient anomaly and analyses for various influential factors

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Geodesy and Geodynamics 2024年第4期15卷 386-396页

作者： Huan Xu Jinhai Yu Yanyan Zeng Qiuyu Wang Yuwei Tian Zhongmiao Sun college of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina Beijing Institute of surveying and Mapping BeijingChina National Key Laboratory of Geoinformation Engineering Xi'an 710054China

The prediction of bathymetry has advanced significantly with the development of satellite ***,the majority of its data originate from marine gravity *** this study,based on the expression of vertical gravity gradient(VGG)of a rectangular prism,the governing equations for determining sea depths to invert *** governing equation is solved by linearization through an iterative process,and numerical simulations verify its algorithm and its *** also study the processing methods of different interference *** regularization method improves the stability of the inversion process for errors.A piecewise bilinear interpolation function roughly replaces the low-frequency error,and numerical simulations show that the accuracy can be improved by 41.2%after this *** variable ocean crust density,simulation simulations verify that the root-mean-square(RMS)error of prediction is approximately 5 m for the sea depth of 6 km if density is chosen as the average ***,two test regions in the South China Sea are predicted and compared with ship soundings data,RMS errors of predictions are 71.1 m and 91.4 m,respectively.

关键词： Rectangular prism Vertical gravity gradient Bathymetry Numerical simulation Prediction error

Methods for ice velocity mapping in West Antarctica using historical optical satellite images

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Advances in Polar Science 2024年第2期35卷 252-263页

作者： ZHANG Yujie AN Lu TANG Leyue LI Hongwei HE Meixi LI Rongxing Center for Spatial Information Science and Sustainable Development Applications Tongji UniversityShanghai 200092China college of surveying and Geo-Informatics Tongji UniversityShanghai 200092China

The Antarctic Ice Sheet harbors more than 90%of the Earth ice mass,with significant losses experienced through dynamic thinning,particularly in West *** crucial aspect of investigating ice mass balance in historical periods preceding 1990 hinges on the utilization of ice velocities derived from optical satellite *** employed declassified satellite images and Landsat images with normalized cross correlation based image matching,adopting an adaptive combination of skills and methods to overcome challenges encountered during the mapping of historical ice velocity in West Antarctica.A basin-wide synthesis velocity map encompassing the coastal regions of most large-scale glaciers and ice shelves in West Antarctica has already been successfully *** results for historical ice velocities cover over 70%of the grounding line in most of the West Antarctic *** adjustments,we uncovered overestimations in ice velocity measurements over an extended period,transforming our ice velocity map into a spatially deterministic,temporally average *** all velocity measurements,Thwaites Glacier exhibited a notable spatial variation in the fastest ice flowline and velocity *** distributions on Thwaites Glacier displayed a clear consistency with the positions of subsequent front calving events,offering insights into the instabilities of ice shelves.

关键词： Antarctica ice velocity overestimation correction historical imagery

Status and trends in the stability of the three largest ice shelves in Antarctica

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Science China Earth Sciences 2024年第8期67卷 2615-2632页

作者： Rongxing LI Guojun LI Lu AN Menglian XIA Da LV Yuan CHENG Aiguo ZHAO Tian CHANG Xiangbin CUI Shengkai ZHANG Shijie LIU Yixiang TIAN Weian WANG Center for Spatial Information Science and Sustainable Development Applications Tongji UniversityShanghai 200092China college of surveying and Geo-informatics Tongji UniversityShanghai 200092China Postdoctoral Research Station of Shanghai surveying and Mapping Institute Shanghai 200063China Key Laboratory of Spatial-temporal Big Data Analysis and Application of Natural Resources in Megacities Shanghai 200063China Institute for Conservation of Cultural Heritage School of Cultural Heritage and Information ManagementShanghai UniversityShanghai 200444China Polar Research Institute of China Shanghai 200136China Chinese Antarctic Center of surveying and Mapping Wuhan UniversityWuhan 430079China

The Ross,Filchner-Ronne,and Amery ice shelves are the three largest ice shelves in Antarctica,playing a crucial role in supporting the Antarctic ice ***,current studies on the stability of the three largest ice shelves primarily focus on singular or limited factors,lacking a comprehensive assessment of multiple *** systematically and in-depth study the stability and trend of the three largest ice shelves,we comprehensively collected and analyzed key parameters,including elevation changes,basal melting,surface meltwater,major rifts propagation rate,suture zones,ice front area change rate,grounding lines,ice velocity,and mass ***,we selected the collapsed Larsen B Ice Shelf(LBIS),the rapidly changing and structurally weakened Pine Island Ice Shelf(PIIS),and the accelerating Totten Ice Shelf(TIS)as reference ice *** comparing and analyzing the key parameters between these reference ice shelves and the three largest ice shelves,we find the status and trends in the stability of the *** findings reveal that most key parameters of the three largest ice shelves present relatively minor variations compared to those of the reference ice ***,50%of the parameters are smaller than those of the accelerating TIS,88%are smaller than those of the rapidly changing PIIS,and all parameters are smaller than those of the collapsed ***,after analyzing parameters that are not smaller than those of the TIS,it is observed that they remain in a stable ***,the three largest ice shelves are currently undergoing natural changes that do not threaten their stability in the short ***,the evolution of the ice shelves under global climate change remains uncertain,making long-term observation and monitoring essential to assess their impact on sea level rise.

关键词： Three largest ice shelves in Antarctica Key parameters Remote sensing monitoring Ice shelf stability Sea level change

Refined acoustic holography via nonlocal metasurfaces

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 113-123页

作者： Shuhuan Xie Hongyu Ma Junmei Cao Fangshuo Mo Qian Cheng Yong Li Tong Hao Institute of Acoustics School of Physics Science and EngineeringTongji UniversityShanghai 200092China Center for Spatial Information Science and Sustainable Development Applications Tongji UniversityShanghai 200092China college of surveying and Geo-Informatics Tongji UniversityShanghai 200092China

Holography can provide the desired wavefront phase and/or amplitude for imaging,particle manipulation,bacteria trapping,and cell patterning in optics and ***,previous work on acoustic holography is mostly based on local design optimization,either using active control of the sound source or relying on the structural design to provide the desired *** precise control over the acoustic field remains a significant ***,we realize refined single-plane symmetric binary amplitude,asymmetric intensity gradient amplitude,and bi-objective hologram through the non-local holographic imaging theory that considers the acoustic coupling of structural units in *** taking into account the self-radiation and mutual radiation between many small units on a plate of well-designed thickness,as well as the transmission through the plate's apertures,we can effectively regulate the sound field behind the *** demonstrate the effectiveness of our approach through numerical simulations and experiments,showcasing a circle,a black hole,and a bi-objective with a circle and a square ***,the acoustic black hole hologram precisely reconstructs the intensity gradient distribution at two bright *** non-local holographic imaging theory is valuable for the fine-intensity regulation of the sound field and is expected to be applied in ultrasound diagnosis and treatment,medical imaging,and other fields.

关键词： acoustic holograms non-local interactions fine intensity modulation acoustic metasurfaces