Dongming Qin , Lv Zhou , Xiang Huang , Yuanjin Pan , Hongming Li , Jiao Xu , Ziyan Luo
{"title":"Multifactor analysis of surface deformation dynamics during economic development","authors":"Dongming Qin , Lv Zhou , Xiang Huang , Yuanjin Pan , Hongming Li , Jiao Xu , Ziyan Luo","doi":"10.1016/j.asr.2024.11.017","DOIUrl":"10.1016/j.asr.2024.11.017","url":null,"abstract":"<div><div>Surface deformation presents considerable hazards, significantly complicating the safeguarding of coastal urban infrastructure. Coastal region infrastructure and buildings are at risk due to climate change, sea level rise, and potential geohazards. This study aims to investigate the coupling between surface deformation and driving factors during the economic development of the Tianjin-Langfang region. Time series interferometric synthetic aperture radar technology is crucial for monitoring the spatiotemporal evolution of coastal cities in preventing geological disasters. SBAS-InSAR technology was utilized in long sequence observations, revealing that surface deformation in the Tianjin area from 2016 to 2023 ranged between –50 to 30 mm/year, and it showed a trend of first decreasing and then rising since 2016. During the research period, comprehensive analysis was conducted using data such as rainfall, land use conversion, groundwater depth characteristics, and seasonal changes. It was found that the deformation in the study area is closely related to key economic development industries. Analysis of groundwater aquifer depth and rainfall data revealed spatiotemporal heterogeneity in deformation rebound. Specifically, surface deformation was greater during months with little or no rainfall compared to periods of precipitation. We discussed the intensity of surface deformation and, in conjunction with the geological environment, provided assessments and recommendations for buildings and infrastructure in severely affected areas.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 3","pages":"Pages 2632-2651"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143170908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Analysis of multipath effects on LEO ranging-based positioning using BPSK and BOC signals in urban areas","authors":"Qi Zhang, Bing Xu","doi":"10.1016/j.asr.2024.11.049","DOIUrl":"10.1016/j.asr.2024.11.049","url":null,"abstract":"<div><div>Low Earth orbit (LEO) satellites have emerged as a promising solution for positioning in environments where traditional Global Navigation Satellite System (GNSS) faces challenges, such as urban canyons. However, the impact of multipath effects on LEO positioning in such urban settings remains unclear. This study investigates the influence of multipath effects on LEO ranging-based positioning, considering signals with binary phase shift keying (BPSK) and binary offset carrier (BOC) modulations. Theoretical analysis reveals that LEO signals exhibit larger Doppler differences between the direct signal and the reflected signal. This characteristic holds particular promise for mitigating multipath effects, especially when utilizing a high frequency carrier. Subsequently, the study assesses the performance of LEO range measurements and positioning under multipath conditions through a simulated LEO constellation. Comparative analyses are conducted with GNSS performance as benchmarks. Additionally, the effectiveness of BOC modulation in enhancing LEO pseudorange positioning accuracy is observed. The results demonstrate that BOC signals can achieve higher ranging and positioning accuracy than BPSK signals. This finding underscores the potential of LEO satellites as reliable alternatives for navigation in challenging urban environments, highlighting the importance of modulation techniques in optimizing positioning performance.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 3","pages":"Pages 3298-3309"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143171079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hamza El Behja , Abdelmounim El M’rini , Driss Nachite , Mohammed Bouchkara , Khalid El Khalidi , Mohamed Maanan , Bendahhou Zourarah , Mohamed Abioui
{"title":"Exploring morphometry, hydrodynamics, and surface sediment composition in Khenifiss lagoon: Insights from a shallow coastal environment in Southern Morocco","authors":"Hamza El Behja , Abdelmounim El M’rini , Driss Nachite , Mohammed Bouchkara , Khalid El Khalidi , Mohamed Maanan , Bendahhou Zourarah , Mohamed Abioui","doi":"10.1016/j.asr.2024.11.003","DOIUrl":"10.1016/j.asr.2024.11.003","url":null,"abstract":"<div><div>Coastal lagoons are widely recognized as highly dynamic and intricate ecosystems within coastal environments, playing a crucial role in supporting both human communities and biodiversity. However, these coastal ecosystems are confronted with a multitude of challenges stemming from both natural phenomena and human activities. Hence, acquiring a comprehensive understanding of coastal lagoon dynamics is imperative for safeguarding and ensuring the sustainability of these ecosystems, relying on discerning the intricate interplay between hydrodynamic and sedimentological factors and processes. In Morocco, the Khenifiss lagoon is recognized as the largest lagoon and the most significant wetland along the Atlantic coast, designated as a protected area under the Ramsar Convention since 1980. However, the lagoon is confronted with the challenge of inlet and channel narrowing due to heightened sediment transport and accumulation toward its interior, along with dune advancement. This paper aims to establish correlations between morphometry, hydrodynamic conditions, and surface sediment composition to categorize the main channel of Khenifiss lagoon according to sedimentary environmental conditions. This categorization aims to delineate zones characterized by high, moderate, and low energy levels. Such classification will offer valuable insights into the dynamic interactions governing the lagoon’s ecosystem by identifying areas prone to resuspension and deposition. The study categorized the main channel of the Khenifiss lagoon into distinct zones based on hydrodynamic conditions. Areas with high energy levels, including the entrance zone and the narrowest central section, featured the highest current velocities, fostering conditions favoring the resuspension of fine materials. Zones with moderate energy levels, such as the downstream main channel and sinuous sections, exhibited moderate current velocities and a predominance of fine sand over medium sand fractions, along with observed reductions in current velocity. Areas characterized by low energy levels, encompassing the upstream main channel, are marked by slower current velocities and shallow depths, facilitating the deposition of fine and very fine sediment. Finally, areas with very low energy and calm conditions, well-protected from strong currents, prevent the reworking of sediments and facilitate their accumulation. This study highlights the importance of integrating sedimentological, hydrodynamic, and morphometric analyses as a valuable approach for monitoring coastal ecosystems and understanding the morphodynamics of coastal lagoons. This approach guides ecosystem management, such as targeted conservation efforts, erosion control, and habitat protection, while also supporting informed coastal development and adaptive management strategies to ensure the long-term sustainability and protection of the Khenifiss lagoon.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 3","pages":"Pages 2550-2568"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143171691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yunong Shang , Changxuan Wen , Yang Sun , Hao Zhang , Yang Gao
{"title":"Active solar eclipse avoidance on the distant retrograde orbit of the Earth-Moon system","authors":"Yunong Shang , Changxuan Wen , Yang Sun , Hao Zhang , Yang Gao","doi":"10.1016/j.asr.2024.11.027","DOIUrl":"10.1016/j.asr.2024.11.027","url":null,"abstract":"<div><div>Lighting condition is a significant concern for spacecraft because it is directly related to their power and thermal subsystems. For spacecraft moving on a Distant Retrograde Orbit (DRO) of the Earth-Moon System, the lighting condition is severe because the DRO faces frequent long-duration solar eclipses. This study proposes a solar eclipse avoidance strategy for DRO missions. First, the lighting condition on a stable nominal DRO is analyzed, which reveals that long-duration solar eclipses are inevitable and active avoidance maneuvers are essential. Then, a close-loop three-impulse maneuver strategy is developed to deviate the trajectory from the nominal DRO and avoid a single shadow region of the Earth (or the Moon). The analytical solution of the first velocity impulse required for orbit correction at an arbitrary position is derived. The optimal position of imposing the velocity impulse is obtained using a nonlinear programming-based optimization algorithm. Finally, a coordinated shadow avoidance algorithm is proposed to simultaneously avoid the shadow of the Earth and the Moon. Simulations show that the proposed strategy successfully keeps the flying trajectory outside the shadow regions in a 4-year mission time at an average annual velocity impulse cost of 46.936 m/s.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 3","pages":"Pages 2970-2981"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143172002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ionospheric changes immediately before the 2023 February Kahramanmaras earthquakes, Turkey","authors":"Ihsan Naufal Muafiry , Irwan Meilano , Dudy D. Wijaya , Erman Sentürk , Kosuke Heki","doi":"10.1016/j.asr.2024.11.011","DOIUrl":"10.1016/j.asr.2024.11.011","url":null,"abstract":"<div><div>The East Anatolian Fault in southern Turkey ruptured on 6 February 2023, causing a M<sub>w</sub> 7.8 earthquake. Another large earthquake of M<sub>w</sub> 7.5 occurred to the north of the first event ∼9 h later. Here we look for ionospheric precursors immediately before these earthquakes, like those found ∼40 min before the 2011 Tohoku-oki earthquake, Japan, by using the total electron content data obtained by global navigation satellite system receivers. Considering that the changes are small, we first inferred the leading times and the intensities of the anomalies using their empirical relationship with M<sub>w</sub> from ∼20 past large earthquakes. For the first earthquake, we found that a positive change of TEC trends started ∼23 min before the rupture and that the anomaly reached ∼2 % of the background. These values were consistent with past events. On the other hand, medium-scale traveling ionospheric disturbance activity hampered convincing detection of changes immediately before the second earthquake.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 3","pages":"Pages 3150-3158"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143172063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Earth observation satellite imaging task scheduling with metaheuristics: Multi-level clustering and priority-driven pre-scheduling","authors":"Mohamed Elamine Galloua, Shuai Li, Jiahao Cui","doi":"10.1016/j.asr.2024.11.023","DOIUrl":"10.1016/j.asr.2024.11.023","url":null,"abstract":"<div><div>Daily planning and scheduling of Agile Earth Observation Satellite (AEOS) observation tasks are enormously challenging due to their inherent complexity. This complexity stems from the vast number of observations that need to be coordinated and the multiple constraints that must be considered. In this study, we propose a comprehensive framework consisting of three steps to effectively tackle these challenges. To begin with, we employ a Multi-Level Clustering technique (MLC) to mitigate the problem complexity. Additionally, we integrate a Fixed High Priority First (FHPF) algorithm for tasks pre-scheduling. This algorithm effectively manages conflicts in time resource allocation for observation tasks at the lowest cluster level. Finally, we conduct a comparative analysis of four metaheuristic algorithms, integrating the pre-scheduled task clusters from the MLC-FHPF module as input for the main scheduling process. Our strategy aims to overcome the limitations of existing methods by incorporating continuous time modeling and accounting for “Fixed Time Maneuver” for time-dependent transition time constraints. Real-world evaluations highlight the resilience and effectiveness of our MLC-FHPF framework when integrated with various metaheuristic algorithms. Our approach significantly outperforms standard metaheuristics in terms of efficacy and efficiency. Notably, the GA MLC-FHPF algorithm consistently surpasses BDP-ILS and ALNS, especially in large-scale scenarios. It adapts effectively to different task densities and scales, maintaining optimized scheduling performance and efficient processing times.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 3","pages":"Pages 2929-2953"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143172104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R.K. Choudhary, K.M. Ambili, C. Vineeth, Ajay Potdar, Md. Mosarraf Hossain, Tarun K. Pant
{"title":"Indian Network for Space Weather Impact Monitoring (InSWIM): An initiative to observe and model the low latitude ionosphere over the Indian longitudes","authors":"R.K. Choudhary, K.M. Ambili, C. Vineeth, Ajay Potdar, Md. Mosarraf Hossain, Tarun K. Pant","doi":"10.1016/j.asr.2024.11.025","DOIUrl":"10.1016/j.asr.2024.11.025","url":null,"abstract":"<div><div>The Space Physics Laboratory (SPL) of Vikram Sarabhai Space Centre (VSSC) has launched a science program called the Indian network for Space Weather Impact Monitoring (InSWIM) to monitor the effects of Space Weather events on the Indian low-latitude ionosphere-thermosphere system. This program aims to study the impact of Space weather on the Indian ionospheric region and develop an Ionospheric Model. The InSWIM network stations will be equipped with instruments such as Global Navigation Satellite Systems (GNSS) receivers, Low Earth Orbit (LEO) receivers, ionosondes, magnetometers, and airglow photometers/imagers. Currently, multi-frequency, multi-constellation GNSS Receiver systems are operational at various stations in India. This network will enable us to understand (a) the quiet-time variability of the ionosphere over the Indian low-latitude region, (b) comprehensively study the response of the low-latitude ionosphere specific to the Indian longitudes under different space weather conditions, with the goal of understanding the various physical mechanisms causing variability in the ionospheric regions, and (c) develop an ionospheric model to reduce ionospheric errors in GNSS systems. Additionally, this network will provide complementary information for rocket and satellite-based experiments. This paper aims to provide details of the InSWIM network to the scientific community for its possible use in monitoring and studying the impact of space weather on the near-Earth space environment.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 3","pages":"Pages 3179-3196"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143171233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pavel Klimov , Vera Nikolaeva , Konstantin Shchelkanov , Roman Saraev , Ksenia Sigaeva , Andrei Kotikov , Alexander Belov , Boris Kozelov , Alexei Murashov , Alexei Roldugin
{"title":"Optical measurements of precipitating relativistic electron microbursts during geomagnetic disturbance and pulsating aurora","authors":"Pavel Klimov , Vera Nikolaeva , Konstantin Shchelkanov , Roman Saraev , Ksenia Sigaeva , Andrei Kotikov , Alexander Belov , Boris Kozelov , Alexei Murashov , Alexei Roldugin","doi":"10.1016/j.asr.2024.11.035","DOIUrl":"10.1016/j.asr.2024.11.035","url":null,"abstract":"<div><div>Mechanisms of formation and losses of radiation belts are the most important questions of magnetospheric physics, especially in a subsecond temporal scale. Energetic particles release their energy in the atmosphere producing fluorescent emission in characteristic wavelength bands. This emission is measurable and can be an additional information source on the spatiotemporal structure of particle fluxes and spectra. Here we present the world’s first measurements of UV-microbursts during geomagnetic disturbance and pulsating aurora caused by high-energy electron precipitation. It demonstrates that fundamental questions of magnetospheric physics mentioned above can be addressed by using the optical measurements by highly sensitive photometers with high temporal resolution. Such a photometer was installed at Verkhnetulomsky observatory at Kola Peninsula and measured a series of short (less than 0.5 s) pulses of emission with an angular size of bright spot <span><math><mrow><mo>∼</mo></mrow></math></span>0.2 rad. Simultaneous measurements of high-energy electron fluxes made by the NOAA-19 satellite and fine temporal structure of geomagnetic pulsations demonstrate a magnetospheric origin of the observed events.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 3","pages":"Pages 3210-3219"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143171235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Provision of land use and forest density maps in semi-arid areas of Iran using Sentinel-2 satellite images and vegetation indices","authors":"Saeedeh Eskandari , Seyed Kazem Bordbar","doi":"10.1016/j.asr.2024.10.060","DOIUrl":"10.1016/j.asr.2024.10.060","url":null,"abstract":"<div><div>Zagros forests of Iran have several environmental, ecological, and socioeconomic values which provide the unique habitats for many endemic species. However, these ecosystems have severely been destroyed by many anthropogenic and natural factors in recent years. Knowledge of area, distribution, and density of these forests and current natural and human-made land uses inside these ecosystems is necessary for protective management of Zagros forests. This research was performed to obtain the land use and forest density maps in Zagros vegetative area of Fars province in southwestern Iran using Sentinel-2A, vegetation indices, Google Earth, and field data. First, the boundary of Zagros forests in Fars province was digitized on Google Earth images. Then, Sentinel-2A satellite images covering the forest region in Fars province were obtained from Copernicus website. A pilot area (16000 ha) in the province was considered to investigate the precision of different classification methods. Then, Sentinel-2A satellite image of pilot region was classified by some supervised classification methods (ML: maximum likelihood, MD: minimum distance, MaD: mahalanobis distance, SAM: spectral angle mapper, NN: neural network, SVM: support vector machine, and RF: random forest). In addition, the efficiency of different vegetation indices (NDVI, TNDVI, SAVI, and RVI) was evaluated for classifying the forest density in the pilot region. Furthermore, pilot area was considered to test the precision of Google Earth satellite images in this study. For this purpose, 270 field samples were taken as square plots in nine land uses. Selection of the plots inside each land use was randomly. After initial analysis, all satellite images covering the forest area in Fars province were classified by the most accurate algorithm (SVM) to obtain the land use map. On the other hand, the most accurate vegetation index (SAVI) was used to classify the forest density in the study area. Validation of final maps was performed using several random plots on Google Earth images. The initial results of this research indicated that Google Earth images have an overall accuracy (<em>OA</em>) of 96 % compared to ground truth in Zagros vegetative area of Fars province. Results of land use map showed that Zagros forest has covered an area of 794651.79 ha in Fars province. The findings of this research demonstrated that SVM algorithm (<em>OA</em>: 92.94 %, and <em>k</em>: 0.85) has efficiently classified the land uses in Fars province. In addition, SAVI (r<sup>2</sup> = 0.719, p < 0.001) has highly been correlated to the forest density in Zagros vegetative area of Fars province. Therefore, land use mapping using SVM algorithm and Sentinel-2A images, and forest density mapping using SAVI is highly recommended in Zagros forests of Fars province in time series which are essential for protective management of these forests in spatio-temporal scale.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 3","pages":"Pages 2506-2534"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143171687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xuyang Meng , Shuanggen Jin , Cheng Liu , Guanjun Zhang , Yunlong Zhang
{"title":"A high precision 3-D tropospheric delay model over China using ERA5 data","authors":"Xuyang Meng , Shuanggen Jin , Cheng Liu , Guanjun Zhang , Yunlong Zhang","doi":"10.1016/j.asr.2024.11.015","DOIUrl":"10.1016/j.asr.2024.11.015","url":null,"abstract":"<div><div>The zenith tropospheric delay (ZTD) is an important error in Global Navigation Satellite System (GNSS) navigation and positioning. The current most empirical tropospheric delay models are two-dimensional with low spatial and temporal resolution and cannot capture high-frequent accurate ZTD variations in small areas and short periods, particularly in Mainland China with diverse climate changes and large terrain differences. In this paper, a high precision three-dimensional (3-D) tropospheric delay grid model (ZTD_3D) over China with a horizontal resolution of 0.25° × 0.25° and a time resolution of 1 h was established with the piecewise function describing the height change of ZTD from 2016 to 2019 fifth-generation European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis data (ERA5). The performance of the proposed model is verified by using radiosonde data and ZTD products from the Crustal Movement Observation Network of China (CMONOC), as well as the global pressure and temperature models (GPT2, GPT3-1 and GPT3-5). Results show that the RMS of ZTD_3D model is 2.04 cm when compared to radiosonde observations, and the accuracy is 55.1 %, 54.7 % and 63.1 % higher than that of GPT3-1 model, GPT3-5 model and GPT2 model, respectively, while the RMS of ZTD_3D model is 3.66 cm when compared to GPS ZTD from CMONOC, and the accuracy is 1.6 % and 29.7 % higher than that of GPT3-5 mode and GPT2 model, respectively. The application of the ZTD_3D model in GNSS precise point positioning (PPP) has showed accuracy improvement in the vertical direction. The model proposed in this study can provide accurate ZTD information and a reliable tropospheric delay correction model for precise GNSS positioning.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 3","pages":"Pages 2599-2613"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143171688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}