Journal of Geodesy最新文献_第10页

Potential of cold-atom airborne gravimetry to improve coastal gravity field and quasigeoid modelling 冷原子机载重力测量法改进沿岸重力场和类地行星建模的潜力

IF 4.4 2区地球科学

Journal of Geodesy Pub Date : 2024-04-13 DOI: 10.1007/s00190-024-01839-0

Dinh Toan Vu, Sylvain Bonvalot, Lucia Seoane, Germinal Gabalda, Dominique Remy, Sean Bruinsma, Yannick Bidel, Alexandre Bresson, Nassim Zahzam, Didier Rouxel, Corinne Salaün, Marie-Françoise Lalancette, René Forsberg, Tim Jensen, Olivier Jamet

{"title":"Potential of cold-atom airborne gravimetry to improve coastal gravity field and quasigeoid modelling","authors":"Dinh Toan Vu, Sylvain Bonvalot, Lucia Seoane, Germinal Gabalda, Dominique Remy, Sean Bruinsma, Yannick Bidel, Alexandre Bresson, Nassim Zahzam, Didier Rouxel, Corinne Salaün, Marie-Françoise Lalancette, René Forsberg, Tim Jensen, Olivier Jamet","doi":"10.1007/s00190-024-01839-0","DOIUrl":"https://doi.org/10.1007/s00190-024-01839-0","url":null,"abstract":"<p>We investigate using the GIRAFE cold-atom gravimeter during an airborne gravity survey for improving gravity field and quasigeoid modelling. The study is conducted over the Bay of Biscay, France. Geoid/quasigeoid determination is usually a major challenge over such coastal areas due to scarce and inconsistent gravity data. In a first step, the GIRAFE dataset is analysed and compared with available surface gravity data as well as with global altimetry models from UCSD and DTU. The comparisons indicate that the DTU model is better than the UCSD model within around 10 km from the coastline. Furthermore, recent satellite altimeter missions significantly improve the altimetry models in coastal areas. A significant bias (− 4.00 mGal) in shipborne data is also found from this comparison. In a second step, eight quasigeoid solutions are calculated to evaluate the contribution of GIRAFE data. This contribution reaches 3 cm in terms of height anomaly for DTU21 while being much larger for UCSDv31 and shipborne data. Finally, the quasigeoid solutions are validated using GNSS-levelling data. The results indicate that using GIRAFE data improves by approximately 50% the quality of quasigeoid models over land near the coast. The highest accuracy, around 1 cm, is achieved when GIRAFE data are merged with refined gravity data. Importantly, the standard deviation is just 1.2 cm when compared with GNSS-levelling points if using only GIRAFE data over marine areas, which is very close to the 1 cm goal of geoid/quasigeoid model determination in modern geodesy. This study thus confirms the benefits of performing airborne gravity survey using quantum sensors.</p>","PeriodicalId":54822,"journal":{"name":"Journal of Geodesy","volume":"171 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140551885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Accounting for residual errors in atmosphere–ocean background models applied in satellite gravimetry 考虑卫星重力测量中应用的大气-海洋背景模型的残余误差

IF 4.4 2区地球科学

Journal of Geodesy Pub Date : 2024-04-10 DOI: 10.1007/s00190-024-01832-7

Linus Shihora, Zhijun Liu, Kyriakos Balidakis, Josefine Wilms, Christoph Dahle, Frank Flechtner, Robert Dill, Henryk Dobslaw

{"title":"Accounting for residual errors in atmosphere–ocean background models applied in satellite gravimetry","authors":"Linus Shihora, Zhijun Liu, Kyriakos Balidakis, Josefine Wilms, Christoph Dahle, Frank Flechtner, Robert Dill, Henryk Dobslaw","doi":"10.1007/s00190-024-01832-7","DOIUrl":"https://doi.org/10.1007/s00190-024-01832-7","url":null,"abstract":"<p>The Atmosphere and Ocean non-tidal De-aliasing Level-1B (AOD1B) product is widely used in precise orbit determination and satellite gravimetry to correct for transient effects of atmosphere–ocean mass variability that would otherwise alias into monthly mean global gravity fields. The most recent release is based on the global ERA5 reanalysis and ECMWF operational data together with simulations from the general ocean circulation model MPIOM consistently forced with fields from the corresponding atmospheric dataset. As background models are inevitably imperfect, residual errors will consequently propagate into the resulting geodetic products. Accounting for uncertainties of the background model data in a statistical sense, however, has been shown before to be a useful approach to mitigate the impact of residual errors leading to temporal aliasing artefacts. In light of the changes made in the new release RL07 of AOD1B, previous uncertainty assessments are deemed too pessimistic and thus need to be revisited. We here present an analysis of the residual errors in AOD1B RL07 based on ensemble statistics derived from different atmospheric reanalyses, including ERA5, MERRA2 and JRA55. For the oceans, we investigate the impact of both the forced and intrinsic variability through differences in MPIOM simulation experiments. The atmospheric and oceanic information is then combined to produce a new time-series of true errors, called AOe07, which is applicable in combination with AOD1B RL07. AOe07 is further complemented by a new spatial error variance–covariance matrix. Results from gravity field recovery simulation experiments for the planned Mass-Change and Geosciences International Constellation (MAGIC) based on GFZ’s EPOS software demonstrate improvements that can be expected from rigorously implementing the newly available stochastic information from AOD1B RL07 into the gravity field estimation process.\u0000</p>","PeriodicalId":54822,"journal":{"name":"Journal of Geodesy","volume":"6 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140541276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Simulation analysis on resonance and direct approaches for determining free core nutation parameters with celestial pole offsets 模拟分析共振和直接方法，确定具有天极偏移的自由核心转角参数

IF 4.4 2区地球科学

Journal of Geodesy Pub Date : 2024-04-09 DOI: 10.1007/s00190-024-01835-4

Xiaoming Cui, Ning Li, Lizhuo Gong, Weiwei Yang, Jianqiao Xu, Jiangcun Zhou, Mingqiang Hou, Heping Sun

{"title":"Simulation analysis on resonance and direct approaches for determining free core nutation parameters with celestial pole offsets","authors":"Xiaoming Cui, Ning Li, Lizhuo Gong, Weiwei Yang, Jianqiao Xu, Jiangcun Zhou, Mingqiang Hou, Heping Sun","doi":"10.1007/s00190-024-01835-4","DOIUrl":"https://doi.org/10.1007/s00190-024-01835-4","url":null,"abstract":"<p>Diurnal tidal oscillations in the coupled atmosphere–ocean system generate important contributions to the Earth’s free core nutation (FCN) and annual and sub-annual components of forced nutation in the celestial pole offsets. The determination of FCN parameters cannot avoid the influence of geophysical fluid excitation neither with the direct analysis of FCN signal (direct approaches) nor with the resonance analysis of forced nutation (resonance approaches). There is a significant difference in the FCN parameters obtained with resonance and direct approaches from celestial pole offsets observed through very long baseline interferometry (VLBI). The source of the difference between the two lacks quantitative analysis, which causes difficulties in interpreting the validity of the derived FCN parameters. Using both approaches, we conducted a simulation of celestial pole offsets to quantitatively demonstrate how geophysical fluid excitation affects the determination of FCN parameters from VLBI observations. Using the same excitation source, the FCN period obtained by the direct approach deviated from the set value (430.21 d) by more than 10 d, while the FCN period obtained by the resonance approach showed no deviation from the set value by more than 1 d. The results indicate that the resonance approach more accurately reflects the intrinsic period of the FCN. The impact of atmospheric and oceanic contributions on the determination of the FCN period with the resonance approach was within 2 d. Numerical simulation shows that discrepancies in FCN parameters caused by geophysical excitation were nonnegligible in constructing accurate FCN models.</p>","PeriodicalId":54822,"journal":{"name":"Journal of Geodesy","volume":"87 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140541584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A refined full-spectrum temperature-induced subsurface thermal expansion model and its contribution to the vertical displacement of global GNSS reference stations 经改进的全谱温度诱导地下热膨胀模型及其对全球导航卫星系统基准台站垂直位移的贡献

IF 4.4 2区地球科学

Journal of Geodesy Pub Date : 2024-04-08 DOI: 10.1007/s00190-024-01834-5

Zhao Li, Ran Lu, Weiping Jiang, Danan Dong, Jintao Lei, Yang Lu, Xin Ding, Kaichun Yang, Hua Chen, Qusen Chen

{"title":"A refined full-spectrum temperature-induced subsurface thermal expansion model and its contribution to the vertical displacement of global GNSS reference stations","authors":"Zhao Li, Ran Lu, Weiping Jiang, Danan Dong, Jintao Lei, Yang Lu, Xin Ding, Kaichun Yang, Hua Chen, Qusen Chen","doi":"10.1007/s00190-024-01834-5","DOIUrl":"https://doi.org/10.1007/s00190-024-01834-5","url":null,"abstract":"<p>The thermal expansion effects of GNSS stations are influenced by not only temperature variations, but also bedrock depths and types. Unfortunately, the current studies treat the subsurface GNSS monument and their nearby bedrock as a whole, without taking into account the inconsistencies among bedrock depths and types, while the existing full-spectrum finite element method (FEM) cannot be easily extended to consider the bedrock information. To solve this problem, we propose a refined full-spectrum temperature-induced subsurface thermal expansion model (FSH<sub>BDT</sub>) that considers both seasonal and non-seasonal temperature variations as well as bedrock information based on the half-space harmonic model. Results show that the full-spectrum half-space harmonic model (FSH), which considers only seasonal and non-seasonal temperature variations, can obtain comparable results to the FEM and even outperform the FEM for inland stations. In addition, the depth and type of bedrock have significant effects on the annual amplitude and phase of thermal expansion-induced vertical displacement. In particular, we find that the station displacement increases by more than 1 mm and the annual phase delays by up to 10° for high-latitude and deeper bedrock stations when bedrock depths are taken into account. The FSH<sub>BDT</sub> improves the correlation coefficient between GNSS height and mass load displacements by up to 42.3% compared to the FEM and explains up to 8.2% of the nonlinear variation in the GNSS height time series. Our work confirms the advantage of rigorous subsurface thermal expansion modeling to correct the nonlinear variations of global GNSS stations, which might provide a potential opportunity to improve the terrestrial reference frame toward the goal of 1 mm accuracy.</p>","PeriodicalId":54822,"journal":{"name":"Journal of Geodesy","volume":"84 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140538351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

RANSAC-based instantaneous real-time kinematic positioning with GNSS triple-frequency signals in urban areas 基于 RANSAC 的瞬时实时运动学定位与城市地区的 GNSS 三频信号

IF 4.4 2区地球科学

Journal of Geodesy Pub Date : 2024-04-06 DOI: 10.1007/s00190-024-01833-6

{"title":"RANSAC-based instantaneous real-time kinematic positioning with GNSS triple-frequency signals in urban areas","authors":"","doi":"10.1007/s00190-024-01833-6","DOIUrl":"https://doi.org/10.1007/s00190-024-01833-6","url":null,"abstract":"<h3>Abstract</h3> <p>The demand for high-precision positioning has risen substantially in modern urban settings. In that regard, Global Navigation Satellite Systems (GNSS) offer several advantages such as global coverage, real-time capability, high accuracy, ease of use, and cost-effectiveness. The accuracy of GNSS-based positioning, however, suffers in urban environments due to signal blockage, reflection, and diffraction, which makes it difficult to fix ambiguities correctly within a real-time kinematic (RTK). To address this issue, this paper applies random sample consensus (RANSAC) to develop a novel single-epoch triple-frequency RTK positioning method. In our proposed method, the ambiguities of the extra-wide-lane, wide-lane, and original frequencies are resolved sequentially. RANSAC then detects and excludes incorrectly fixed ambiguities. To validate the effectiveness of the proposed method, two static experiments (cases 1 and 2) and one dynamic experiment (case 3) were conducted in representative urban areas. The findings demonstrate that the proposed method outperforms all comparative methods in positional availability, with comparable positional accuracy in terms of root-mean-square errors (RMSEs). In cases 1, 2, and 3, the proposed method achieves 3D RMSEs of 2.74, 4.29, and 20.35 cm, and the positional availabilities of 100%, 75.0%, and 73.1%, using a 10-degree mask angle (and a carrier-to-noise ratio (<em>C</em>/<em>N</em><sub>0</sub>) threshold 35 dB-Hz). The corresponding RMSEs (positional availabilities) of comparative methods are from 1.51 to 4.04 cm (75.7 to 96.3%) in case 1, 4.19 to 7.78 cm (34.5 to 49.9%) in case 2, and 23.52 to 37.54 cm (15.4 to 33.9%) in case 3, respectively. Compared to these methods, the proposed method shows improvements of positional availabilities between 3.7 and 24.3 percentage points in case 1, between 25.1 and 40.5 percentage points in case 2, and between 39.2 and 57.7 percentage points in case 3.</p>","PeriodicalId":54822,"journal":{"name":"Journal of Geodesy","volume":"13 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140533967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Global, spatially explicit modelling of zenith wet delay with XGBoost 利用 XGBoost 对天顶湿延迟进行全球空间显式建模

IF 4.4 2区地球科学

Journal of Geodesy Pub Date : 2024-04-05 DOI: 10.1007/s00190-024-01829-2

{"title":"Global, spatially explicit modelling of zenith wet delay with XGBoost","authors":"","doi":"10.1007/s00190-024-01829-2","DOIUrl":"https://doi.org/10.1007/s00190-024-01829-2","url":null,"abstract":"<h3>Abstract</h3> <p>Radio signals transmitted by Global Navigation Satellite System (GNSS) satellites experience tropospheric delays. While the hydrostatic part, referred to as zenith hydrostatic delay (ZHD) when mapped to the zenith direction, can be analytically modelled with sufficient accuracy, the wet part, referred to as zenith wet delay (ZWD), is much more difficult to determine and needs to be estimated. Thus, there exist several ZWD models which are used for various applications such as positioning and climate research. In this study, we present a data-driven, global model of the spatial ZWD field, based on the Extreme Gradient Boosting (XGBoost). The model takes the geographical location, the time, and a number of meteorological variables (in particular, specific humidity at several pressure levels) as input, and can predict ZWD anywhere on Earth as long as the input features are available. It was trained on ZWDs at 10718 GNSS stations and tested on ZWDs at 2684 GNSS stations for the year 2019. Across all test stations and all observations, the trained model achieved a mean absolute error of 6.1 mm, respectively, a root mean squared error of 8.1 mm. Comparisons of the XGBoost-based ZWD predictions with independently computed ZWDs and baseline models underline the good performance of the proposed model. Moreover, we analysed regional and monthly models, as well as the seasonal behaviour of the ZWD predictions in different climate zones, and found that the global model exhibits a high predictive skill in all regions and across all months of the year.</p>","PeriodicalId":54822,"journal":{"name":"Journal of Geodesy","volume":"46 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140533963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessment of length-of-day and universal time predictions based on the results of the Second Earth Orientation Parameters Prediction Comparison Campaign 根据第二次地球方位参数预测比较活动的结果对日长和世界时预测进行评估

IF 4.4 2区地球科学

Journal of Geodesy Pub Date : 2024-03-20 DOI: 10.1007/s00190-024-01824-7

{"title":"Assessment of length-of-day and universal time predictions based on the results of the Second Earth Orientation Parameters Prediction Comparison Campaign","authors":"","doi":"10.1007/s00190-024-01824-7","DOIUrl":"https://doi.org/10.1007/s00190-024-01824-7","url":null,"abstract":"<h3>Abstract</h3> <p>Predicting Earth Orientation Parameters (EOP) is crucial for precise positioning and navigation both on the Earth’s surface and in space. In recent years, many approaches have been developed to forecast EOP, incorporating observed EOP as well as information on the effective angular momentum (EAM) derived from numerical models of the atmosphere, oceans, and land-surface dynamics. The Second Earth Orientation Parameters Prediction Comparison Campaign (2nd EOP PCC) aimed to comprehensively evaluate EOP forecasts from many international participants and identify the most promising prediction methodologies. This paper presents the validation results of predictions for universal time and length-of-day variations submitted during the 2nd EOP PCC, providing an assessment of their accuracy and reliability. We conduct a detailed evaluation of all valid forecasts using the IERS 14 C04 solution provided by the International Earth Rotation and Reference Systems Service (IERS) as a reference and mean absolute error as the quality measure. Our analysis demonstrates that approaches based on machine learning or the combination of least squares and autoregression, with the use of EAM information as an additional input, provide the highest prediction accuracy for both investigated parameters. Utilizing precise EAM data and forecasts emerges as a pivotal factor in enhancing forecasting accuracy. Although several methods show some potential to outperform the IERS forecasts, the current standard predictions disseminated by IERS are highly reliable and can be fully recommended for operational purposes.</p>","PeriodicalId":54822,"journal":{"name":"Journal of Geodesy","volume":"158 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140182838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Factor graph-based PPP-RTK for accurate and robust positioning in urban environments 基于因子图的 PPP-RTK 可在城市环境中实现精确而稳健的定位

IF 4.4 2区地球科学

Journal of Geodesy Pub Date : 2024-03-18 DOI: 10.1007/s00190-024-01828-3

Xin Li, Xingxing Li, Xuanbin Wang, Hanyu Chang, Yuxuan Tan, Zhiheng Shen

{"title":"Factor graph-based PPP-RTK for accurate and robust positioning in urban environments","authors":"Xin Li, Xingxing Li, Xuanbin Wang, Hanyu Chang, Yuxuan Tan, Zhiheng Shen","doi":"10.1007/s00190-024-01828-3","DOIUrl":"https://doi.org/10.1007/s00190-024-01828-3","url":null,"abstract":"<p>The PPP-RTK system, which is capable of providing a centimeter-level real-time positioning service for an unlimited number of users, is becoming a promising tool in mass-market applications such as smartphones, the Internet of Things (IoT), and the automotive industry. The extended Kalman filter (EKF) is the conventional method for parameter estimation in the existing PPP-RTK system. Recently, an alternative method known as factor graph optimization (FGO), which fully leverages the time correlation among current and historical measurements, has the potential to further improve the accuracy and robustness of PPP-RTK solutions. In this contribution, a factor graph optimization-based PPP-RTK framework is developed, where raw pseudorange, phase measurements, precise atmospheric corrections, and time-differenced carrier-phase (TDCP) measurements serve as factors in FGO estimators. The continuously tracked phase ambiguities are estimated as the time-invariant state node and propagated by marginalization while ambiguity resolution is conducted independently between epochs. A second optimization process with the utilization of ambiguity-resolved solutions and time-differenced carrier-phase (TDCP) measurements is conducted to further improve the reliability of positioning results. The effectiveness of the proposed method is evaluated by vehicular tests in urban environments. Results indicate that the FGO method could improve the performance of ambiguity resolution by reducing the ambiguity search space and increasing the ratio values, leading to a significant accuracy improvement of 55% in an open-sky environment compared to the traditional EKF-based method. Furthermore, in GNSS signal partly block scenes, the FGO-based PPP-RTK is capable of obtaining more robust and accurate positioning solutions with fewer outliers compared to the EKF method.</p>","PeriodicalId":54822,"journal":{"name":"Journal of Geodesy","volume":"9 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140145942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Correcting flawed orbits with significant along-track offset in LOLA data to remove apparent noise in DEM 修正 LOLA 数据中沿轨道偏移较大的有缺陷轨道，消除 DEM 中的明显噪声

IF 4.4 2区地球科学

Journal of Geodesy Pub Date : 2024-03-16 DOI: 10.1007/s00190-024-01827-4

{"title":"Correcting flawed orbits with significant along-track offset in LOLA data to remove apparent noise in DEM","authors":"","doi":"10.1007/s00190-024-01827-4","DOIUrl":"https://doi.org/10.1007/s00190-024-01827-4","url":null,"abstract":"<h3>Abstract</h3> <p>The lunar orbiter laser altimeter (LOLA) onboard the lunar reconnaissance orbiter has performed high-precision, full-coverage, and high-density laser ranging observations for the entire lunar surface since its launch. Statistics have shown that LOLA has collected 6.94 billion effective altimeter data up to June 2022. Most of the typical orbits in the LOLA dataset have a high quality and exhibit horizontal offsets of almost 7 m and radial offsets of almost 0.5 m. However, there is still a category of orbits in the dataset that will cause apparent noise in the constructed DEM, which is attributed to the orbits with large or anomalous errors. We call such orbits as flawed orbits in this paper. The flawed orbits can be identified and screened by the elevation discrepancy at the crossovers of the orbits. The results show that the flawed orbits are caused by significant along-track errors, which also result in the radial error of up to several kilometers. Moreover, most of the flawed orbits are concentrated in several consecutive time intervals. A correction method is then proposed to correct the flawed orbits in the local region. The position of the flawed orbits is reconstructed using the feature points matching of the DEMs before and after they are removed. Some experimental analyzes show that the apparent terrain artifacts have been eliminated and more identifiable terrain details are reappeared. Identifying and correcting these flawed orbits with significant along-track offsets paves the way for improving the quality of the LOLA data and reconstructing the topography of the Moon.</p>","PeriodicalId":54822,"journal":{"name":"Journal of Geodesy","volume":"41 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140139511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A complete closed-form method for transformation from Cartesian to geodetic coordinates 从直角坐标到大地坐标转换的完整闭式方法

IF 4.4 2区地球科学

Journal of Geodesy Pub Date : 2024-03-05 DOI: 10.1007/s00190-024-01821-w

引用次数: 0