Analysis of regional large-gradient land subsidence in the Alto Guadalentín Basin (Spain) using open-access aerial LiDAR datasets

Land subsidence associated with groundwater overexploitation in the Alto Guadalentín Basin (Spain) aquifer system has been detected during the last decades. In this work, for the first time, we propose a new point cloud differencing methodology to detect land subsidence at basin scale, based on the multiscale model-to-model cloud comparison (M3C2) algorithm. This method is applied to two open-access airborne LiDAR datasets acquired in 2009 and 2016, respectively. First the internal edge connection errors in the different flight lines were addressed by means of a smoothing point cloud method. LiDAR datasets capture information from ground and non-ground points. Therefore, a method combining gradient filtering and cloth simulation filtering (CSF) algorithms was applied to remove non-ground points. The iterative closest point (ICP) algorithm was used for point cloud registration of both point clouds exhibiting a very stable and robust performance. The results show that vertical deformation rates are up to −14 cm/year in the basin from 2009 to 2016, in agreement with the displacement reported by previous studies. LiDAR results have been compared to the velocity measured by continuous GNSS stations and an InSAR dataset. For the GNSS-LiDAR and InSAR-LiDAR comparison, we computed a common 100 × 100 m grid in order to assess any similarities and discrepancies. The results show a good agreement between the vertical displacements obtained from the three different surveying techniques. Furthermore, LiDAR results were compared with the distribution of compressible soil thickness showing a clear relationship. The study underlines the potential of open-access and non-customized LiDAR to monitor the distribution and magnitude of vertical deformations in areas prone to be affected by groundwater-withdrawal-induced land subsidence.This research was funded by the ESA-MOST China DRAGON-5 project (ref. 59339) and by a Chinese Scholarship Council studentship awarded to Liuru Hu (Ref. 202004180062). María I. Navarro-Hernández and Guadalupe Bru are funded by the PRIMA programme supported by the European Union under grant agreement No 1924, project RESERVOIR

Coherent change detection with GNSS-based SAR -Experimental study-

Bistatic Synthetic Aperture Radar (BSAR) systems are under an increasing amount of research activity over the last years. The possibility of the use of transmitters of opportunity has increased the flexibility and the applications of radar systems. One of the options is the use of Global Navigation Satellite Systems (GNSS) as transmitters, such as GPS, GLONASS or the forthcoming Galileo and Beidou, that is used in this study. This thesis is the result of the study of a GNSS-based SAR used for detection of changes that may occur in a scene. Although passive SAR is outclassed by active SAR in terms of SAR imaging performance, Coherent Change Detection applications in passive SAR can be promising. A proof-of-concept study is presented in this thesis. The connection between spatial target change and the level of coherence before and after the change is investigated. The stages of theoretical analysis and experimental setup are described in detail. Simulated scenarios are presented and the experimental results are analysed

시계열 InSAR 기법을 사용하여 비정상적 해수면 상승 기록을 보인 조위관측소의 수직지반변위 평가

학위논문(박사) -- 서울대학교대학원 : 자연과학대학 지구환경과학부, 2021.8. 김덕진.Global sea level rise has been a serious threat to the low-lying coasts and islands around the world. It is important to understand the global and regional sea level changes for preventing the coastal zones. Tide gauges are installed around the world, which directly measures the change in sea level relative to the local datum. Sea level in the past three decades has risen to 1.8 mm/year compared to the sea level rise in the 20th century (3.35 mm/year), estimated by the Intergovernmental Panel on Climate Change (IPCC). However, along with the contributors of sea level rise, vertical land motion (VLM) is indeed an essential component for understanding the regional sea level change; however, its contribution remains still unclear. The VLM is referred to as change in elevation of land at tide gauge due to the regional and local processes by both natural and anthropogenic activities can deteriorate the sea level records and lead to spurious sea level acceleration. Assessing the vertical land motion at tide gauges with the accuracy of sub-millimeters is essential to reconstruct the global and regional sea level rise. Previous studies attempt to observe the vertical land movements at sparse locations through Global Positioning System (GPS). However, the VLM observed from the sparse GPS network makes the estimation uncertain. In this study, an alternative approach is proposed in this study to directly measure the relative vertical land motion including spatial and temporal variations through Synthetic Aperture Radar (SAR) data by using time-series SAR interferometric (InSAR) techniques. This work presents a contribution enhancing the estimation of VLM rates with high spatial resolution over large area using time-series InSAR analysis. First, the C-band Interferometric Wide-swath (IW) mode SAR data from the Sentinel-1 A/B satellite was used in this study to estimate the VLM rates of tide gauges. The Sentinel-1 A/B SAR data were obtained during the period between 2014/10 and 2020/12 (~ 6 years). Stanford Method for Persistent Scatterers – Persistent Scatterer Interferometry (StaMPS-PSI) time-series InSAR algorithm was initially applied to the case study: Pohang tide gauge in the Korean peninsula for monitoring the stability of tide gauge station and its VLM rates during 2014 ~ 2017. For the Pohang tide gauge site, SAR data acquired in both ascending and descending passes and derived the ground movement rates at tide gauge along the line-of-sight direction. The vertical movements from the collocated POHA GPS station were compared with the InSAR derived VLM rates for determining the correlation between the two methods. The VLM rates at the Pohang tide gauge site were -25.5 mm/year during 2014 ~ 2017. This VLM rate at Pohang tide gauge derived by StaMPS-PSI estimates were from the strong dominant scatterers along the coastal regions. Second, for the terrains, with few dominant scatterers and more distributed scatters, a short temporal InSAR pair selection approach was introduced, referred as Sequential StaMPS-Small baselines subset (StaMPS-SBAS) was proposed in this study. Sequential StaMPS-SBAS forms the interferograms of short temporal sequential order (n = 5) to increase the initial pixel candidates on the natural terrains in the vicinity of tide gauges. Sentinel-1 A/B SAR data over ten tide gauges in the Korean peninsula having different terrain conditions were acquired during 2014 ~ 2020; and employed with sequential StaMPS-SBAS to estimate the VLM rates and time-series displacements. The initial pixel density has been doubled and ~ 1.25 times the final coherent pixels identified over the conventional StaMPS-SBAS analysis. Third, the potential for the fully automatic estimation of time-series VLM rates by sequential StaMPS-SBAS analysis was investigated. A fully automatic processing module referred to as ‘Seq-TInSAR’, was developed which has three modules 1) automatically downloads Sentinel-1 Single look complex (SLC) data, precise orbit files, and Digital Elevation Model (DEM); 2) SLC pre-processor: extract bursts, fine Coregistration and stacking and, 3) Sequential StaMPS-SBAS processor: estimates the VLM rates and VLM time-series. Finally, the Seq-TInSAR module is applied to the 100 tide gauges that exhibit abnormal sea level trend with par global mean sea level average. For each tide gauge site, 60 ~ 70 Sentinel-1 A/B SLC scenes were acquired and 300 ~ 350 sequential interferograms were processed to estimate the VLM at tide gauge stations. The final quantitative VLM rates and time-series VLM are estimated for the selected tide gauges stations. Based on the VLM rates, the tide gauges investigated in this study are categorized into different VLM ranges. The in-situ GPS observations available at 12 tide gauge stations were compared with InSAR VLM rates and found strong agreement, which suggests the proposed approach more reliable in measuring the spatial and temporal variations of VLM at tide gauges.전 세계적으로 발생하는 해수면 상승은 저지대 해안과 도서 지역에 심각한 위협으로 작용한다. 해안 지역을 보호하기 위해 전 지구 및 해당 지역의 해수면 변화를 이해하는 것은 대단히 중요하다. 조위 관측소는 전 세계에 설치되어 해당 지역 기준에 따른 해수면 변화를 직접 측정한다. 지난 30 년간 해수면은 IPCC (정부 간 기후 변화 패널)가 추정한 20 세기의 해수면 상승 (3.35mm / 년)대비 1.8mm / 년 가까이 상승하였다. 그러나 해수면 상승의 원인과 함께 연직 지반 운동 (VLM)은 지역 해수면 변화를 이해하는 데 필수적인 요소이지만 그 기여도는 여전히 불분명하다. VLM은 자연 활동과 인간 활동 모두에 의한 지역적 변화로 인해 조위 관측소에서 지반의 고도 변화로 정의되며 해수면 변화 정확도을 악화시키고 유사 해수면 변화의 가속을 초래할 수 있다. 전 세계 및 지역 해수면 상승을 재구성하려면 1 밀리미터 미만의 정확도로 조위 관측소에서 VLM을 평가하는 것이 필수적이다. 이전 연구는 GPS (Global Positioning System)를 통해 제한된 위치에서 VLM 을 관측하려고 시도하였으나 국소적인 GPS 신호들로부터 관측된 VLM으로는 그 추정이 불확실하다. 본 연구에서는 시계열 SAR 간섭계 (InSAR) 기법을 이용하여 SAR (Synthetic Aperture Radar) 데이터를 통해 공간적, 시간적 변화를 포함한 상대적 VLM을 직접 측정하기 위한 대안적 접근 방식을 제안한다. 이 작업은 시계열 InSAR 분석을 사용하여 광대역에 걸쳐 높은 공간 해상도로 VLM 속도의 추정을 향상시키는 데 기여한다. 첫째로, Sentinel-1 A / B 위성의 C-band Interferometric Wide-swath (IW) 모드 SAR 영상이 본 연구에서 조위 관측소의 VLM 속도를 추정하는 데 사용되었다. Sentinel-1 A / B SAR 영상은 2014 년 10 월부터 2020 년 12 월까지 (~ 6 년) 기간 동안 수집되었다. 고정 산란체를 위한 스탠포드 기법 – 고정 산란 간섭계 (StaMPS-PSI) 시계열 InSAR 알고리즘이 한반도 포항 조위 관측소의 2014 ~ 2017 년 동안의 조위 관측소의 안정성과 VLM 속도를 모니터링하기 위해 적용되었다. 포항 조위 관측소 부지의 경우, 위성궤도의 상승 및 하강 경로로 획득한 SAR 영상을 통해 시선 방향을 따라 조위 관측소에서의 지면 이동 속도를 도출하였다. 포항 GPS 관측소의 연직 이동은 두 기법 간의 상관성를 판단하기 위해 InSAR기법으로부터 추정된 VLM 속도와 비교되었다. 포항 조위 관측소의 VLM 속도는 2014 ~ 2017 년의 기간 동안 -25.5mm / 년으로 관측되었다. StaMPS-PSI 추정에 의해 도출 된 포항 조위 관측소의 VLM 속도은 해안 지역의 강한 산란 체에서 기인한다. 둘째로, 강한 산란체가 수가 적고 분산된 산란체가 더 많은 지형의 경우, 본 연구에서 Sequential StaMPS-Small baselines (StaMPS-SBAS)이라는 하는 단기 InSAR 쌍의 선택에 의한 접근 방식이 제안되었다. Sequential StaMPS-SBAS는 짧은 시간 범위(n = 5)의 간섭계 영상을 형성하여 조위 관측소 부근의 자연 지형에서 변화가 적은 화소 선택을 증가시킨다. Sentinel-1 A / B SAR 영상은 2014 년 ~ 2020 년 사이에 서로 다른 지형 조건을 가진 한반도의 10 개 조위 관측소에서 수집되었으며, VLM 속도 및 시계열 변위를 추정하기 위해 Sequential StaMPS-SBAS와 함께 사용되었다. 초기 화소 밀도는 기존 StaMPS-SBAS 분석을 통해 확인 된 최종적인 불변화소 밀도의 약 1.25 배와 두 배로 도출되었다. 셋째로, Sequential StaMPS-SBAS 분석에 의한 시계열 VLM 비율의 완전한 자동 추정 가능성을 조사하였다. Seq-TInSAR라고하는 완전한 자동 처리 모듈이 개발되었으며, 3 개의 하위 모듈로 구성되어있다. 1) Sentinel-1 SLC (Single Look Complex) 영상, 정밀한 궤도 정보 및 DEM (Digital Elevation Model)의 자동 다운로드 2) SLC 전 처리기 : 영상 별 Burst 추출, 정밀한 통합 및 Stacking, 3) Sequential StaMPS-SBAS 프로세서 : VLM 속도 및 VLM 시계열 변위의 추정 마지막으로, Seq-TInSAR 모듈은 동위 평균 해수면 평균으로 비정상적인 해수면 추세를 보이는 100 개의 조위 관측소에 적용된다. 조위 관측소 지점별로 60 ~ 70 개의 Sentinel-1 A / B SLC 영상을 획득하고 300 ~ 350 개의 시계열 간섭계 영상을 처리하여 조위 관측소에서 VLM을 추정하였다. 정량적인 VLM 속도와 시계열 VLM은 선정한 조위 관측소에 대해 추정하였다. VLM 속도을 기반으로 본 연구에서 도출한 조위 관측소는 다양한 VLM 범위로 분류된다. 12 개의 조위 관측소에서 취득한 현장 GPS 관측 자료를 InSAR로부터 추정한 VLM 비율과 비교하여 강력한 상관성을 찾았고, 이는 본 연구에서 제안한 접근 방식이 조위 관측소에서 VLM의 공간적 및 시간적 변화를 측정하는데 신뢰할 수 있는 자료로 사용될 수 있음을 시사한다.Chapter 1. Introduction 1 1.1. Brief overview of sea-level rise 1 1.2. Motivations 4 1.3. Purpose of Research 9 1.4. Outline 12 Chapter 2. Sea Level variations and Estimation of Vertical land motion 14 2.1. Sea level variations 14 2.2. Sea level observations 14 2.3. Long term sea level estimation 19 2.4. Factors contributing tide gauge records: Vertical Land Motion 19 2.5. Brief overview of InSAR and Time-series SAR Interferometry 24 Chapter 3. Vertical Land Motion estimation at Tide gauge using Time-series PS-InSAR technique: A case study for Pohang tide gauge 36 3.1. Background 36 3.2. VLM estimation at Pohang tide gauge using StaMPS-PSI analysis 38 3.3. Development of StaMPS-SBAS InSAR using Sequential InSAR pair selection suitable for coastal environments 55 3.4. Discussion 80 Chapter 4. Application of time-series Sequential-SBAS InSAR for Vertical Land Motion estimation at selected tide gauges around the world using Sentinel-1 SAR data 85 4.1. Description of PSMSL tide gauge data 87 4.2. Sentinel-1 A/B SAR data acquisitions 92 4.3. Automatic Time-series InSAR processing module ”Seq-TInSAR” 93 4.4. Results: Estimation of vertical land motions at selected tide gauges 97 4.5. Comparison of InSAR results with GNSS observations 112 4.6. Discussion 125 Chapter 5. Conclusions and Future Perspectives 128 Abstract in Korean 133 Appendix – A 136 Appendix – B 146 Bibliography 151박

Robust and Flexible Persistent Scatterer Interferometry for Long-Term and Large-Scale Displacement Monitoring

Die Persistent Scatterer Interferometrie (PSI) ist eine Methode zur Überwachung von Verschiebungen der Erdoberfläche aus dem Weltraum. Sie basiert auf der Identifizierung und Analyse von stabilen Punktstreuern (sog. Persistent Scatterer, PS) durch die Anwendung von Ansätzen der Zeitreihenanalyse auf Stapel von SAR-Interferogrammen. PS Punkte dominieren die Rückstreuung der Auflösungszellen, in denen sie sich befinden, und werden durch geringfügige Dekorrelation charakterisiert. Verschiebungen solcher PS Punkte können mit einer potenziellen Submillimetergenauigkeit überwacht werden, wenn Störquellen effektiv minimiert werden. Im Laufe der Zeit hat sich die PSI in bestimmten Anwendungen zu einer operationellen Technologie entwickelt. Es gibt jedoch immer noch herausfordernde Anwendungen für die Methode. Physische Veränderungen der Landoberfläche und Änderungen in der Aufnahmegeometrie können dazu führen, dass PS Punkte im Laufe der Zeit erscheinen oder verschwinden. Die Anzahl der kontinuierlich kohärenten PS Punkte nimmt mit zunehmender Länge der Zeitreihen ab, während die Anzahl der TPS Punkte zunimmt, die nur während eines oder mehrerer getrennter Segmente der analysierten Zeitreihe kohärent sind. Daher ist es wünschenswert, die Analyse solcher TPS Punkte in die PSI zu integrieren, um ein flexibles PSI-System zu entwickeln, das in der Lage ist mit dynamischen Veränderungen der Landoberfläche umzugehen und somit ein kontinuierliches Verschiebungsmonitoring ermöglicht. Eine weitere Herausforderung der PSI besteht darin, großflächiges Monitoring in Regionen mit komplexen atmosphärischen Bedingungen durchzuführen. Letztere führen zu hoher Unsicherheit in den Verschiebungszeitreihen bei großen Abständen zur räumlichen Referenz. Diese Arbeit befasst sich mit Modifikationen und Erweiterungen, die auf der Grund lage eines bestehenden PSI-Algorithmus realisiert wurden, um einen robusten und flexiblen PSI-Ansatz zu entwickeln, der mit den oben genannten Herausforderungen umgehen kann. Als erster Hauptbeitrag wird eine Methode präsentiert, die TPS Punkte vollständig in die PSI integriert. In Evaluierungsstudien mit echten SAR Daten wird gezeigt, dass die Integration von TPS Punkten tatsächlich die Bewältigung dynamischer Veränderungen der Landoberfläche ermöglicht und mit zunehmender Zeitreihenlänge zunehmende Relevanz für PSI-basierte Beobachtungsnetzwerke hat. Der zweite Hauptbeitrag ist die Vorstellung einer Methode zur kovarianzbasierten Referenzintegration in großflächige PSI-Anwendungen zur Schätzung von räumlich korreliertem Rauschen. Die Methode basiert auf der Abtastung des Rauschens an Referenzpixeln mit bekannten Verschiebungszeitreihen und anschließender Interpolation auf die restlichen PS Pixel unter Berücksichtigung der räumlichen Statistik des Rauschens. Es wird in einer Simulationsstudie sowie einer Studie mit realen Daten gezeigt, dass die Methode überlegene Leistung im Vergleich zu alternativen Methoden zur Reduktion von räumlich korreliertem Rauschen in Interferogrammen mittels Referenzintegration zeigt. Die entwickelte PSI-Methode wird schließlich zur Untersuchung von Landsenkung im Vietnamesischen Teil des Mekong Deltas eingesetzt, das seit einigen Jahrzehnten von Landsenkung und verschiedenen anderen Umweltproblemen betroffen ist. Die geschätzten Landsenkungsraten zeigen eine hohe Variabilität auf kurzen sowie großen räumlichen Skalen. Die höchsten Senkungsraten von bis zu 6 cm pro Jahr treten hauptsächlich in städtischen Gebieten auf. Es kann gezeigt werden, dass der größte Teil der Landsenkung ihren Ursprung im oberflächennahen Untergrund hat. Die präsentierte Methode zur Reduzierung von räumlich korreliertem Rauschen verbessert die Ergebnisse signifikant, wenn eine angemessene räumliche Verteilung von Referenzgebieten verfügbar ist. In diesem Fall wird das Rauschen effektiv reduziert und unabhängige Ergebnisse von zwei Interferogrammstapeln, die aus unterschiedlichen Orbits aufgenommen wurden, zeigen große Übereinstimmung. Die Integration von TPS Punkten führt für die analysierte Zeitreihe von sechs Jahren zu einer deutlich größeren Anzahl an identifizierten TPS als PS Punkten im gesamten Untersuchungsgebiet und verbessert damit das Beobachtungsnetzwerk erheblich. Ein spezieller Anwendungsfall der TPS Integration wird vorgestellt, der auf der Clusterung von TPS Punkten basiert, die innerhalb der analysierten Zeitreihe erschienen, um neue Konstruktionen systematisch zu identifizieren und ihre anfängliche Bewegungszeitreihen zu analysieren

Early warning monitoring of natural and engineered slopes with Ground-Based Synthetic Aperture Radar

The first application of ground-based interferometric synthetic-aperture radar (GBInSAR) for slope monitoring dates back 13 years. Today, GBInSAR is used internationally as a leading-edge tool for near-real-time monitoring of surface slope movements in landslides and open pit mines. The success of the technology relies mainly on its ability to measure slope movements rapidly with sub- millimetric accuracy over wide areas and in almost any weather conditions. In recent years, GBInSAR has experienced significant improvements, due to the development of more advanced radar techniques in terms of both data processing and sensor performance. These improvements have led to widespread diffusion of the technology for early warning monitoring of slopes in both civil and mining applications. The main technical features of modern SAR technology for slope monitoring are discussed in this paper. A comparative analysis with other monitoring technologies is also presented along with some recent examples of successful slope monitorin

State-of-the-art in studies of glacial isostatic adjustment for the British Isles: a literature review

Understanding the effects of glacial isostatic adjustment (GIA) of the British Isles is essential for the assessment of past and future sea-level trends. GIA has been extensively examined in the literature, employing different research methods and observational data types. Geological evidence from palaeo-shorelines and undisturbed sedimentary deposits has been used to reconstruct long-term relative sea-level change since the Last Glacial Maximum. This information derived from sea-level index points has been employed to inform empirical isobase models of the uplift in Scotland using trend surface and Gaussian trend surface analysis, as well as to calibrate more theory-driven GIA models that rely on Earth mantle rheology and ice sheet history. Furthermore, current short-term rates of GIA-induced crustal motion during the past few decades have been measured using different geodetic techniques, mainly continuous GPS (CGPS) and absolute gravimetry (AG). AG-measurements are generally employed to increase the accuracy of the CGPS estimates. Synthetic aperture radar interferometry (InSAR) looks promising as a relatively new technique to measure crustal uplift in the northern parts of Great Britain, where the GIA-induced vertical land deformation has its highest rate. This literature review provides an in-depth comparison and discussion of the development of these different research approaches

Spatial Analysis of Land Subsidence in the San Luis Potosi Valley Induced by Aquifer Overexploitation Using the Coherent Pixels Technique (CPT) and Sentinel-1 InSAR Observation

The San Luis Potosi metropolitan area has suffered considerable damage from land subsidence over the past decades, which has become visible since 1990. This paper seeks to evaluate the effects of groundwater withdrawal on land subsidence in the San Luis Potosi Valley and the development of surface faults due to the differential compaction of sediments. For this purpose, we applied the Coherent Pixels Technique (CPT), a Persistent Scatterer Interferometry (PSI) technique, using 112 Sentinel-1 acquisitions from October 2014 to November 2019 to estimate the deformation rate. The results revealed that the deformation areas in the municipality of Soledad de Graciano Sánchez mostly exhibit subsidence values between −1.5 and −3.5 cm/year; whereas in San Luis Potosi these values are between −1.8 and −4.2 cm/year. The PSI results were validated by five Global Navigation Satellite System (GNSS) benchmarks available, providing a data correlation between the results obtained with both techniques of 0.986. This validation suggests that interferometric derived deformations agree well with results obtained from GNSS data. The strong relationship between trace fault, land subsidence,e and groundwater extraction suggests that groundwater withdrawal is resulting in subsidence induced faulting, which follows the pattern of structural faults buried by sediments.This work was supported by the Spanish Ministry of Economy, Industry and Competitiveness (MINECO), the State Agency of Research (AEI) and European Funds for Regional Development (FEDER) under project TEMUSA (TEC2017-85244-C2-1-P and TEC2017-85244-C2-2-P) and by Mexican Council of Science and technology (CONACYT). This paper is also funded by the PRIMA programme supported by the European Union under grant agreement No 1924, project RESERVOIR. It also has been supported by the CommSensLab, which is Unidad de Excelencia Maria de Maeztu MDM-2016-0600 financed by the Agencia Estatal de Investigacion, Spain

Surface deformation analysis in Northeast Italy by using PS-InSAR and GNSS data

In the present study, we exploited the potential of satellite-based geodetic data for detecting and measuring surface displacement in Northeast Italy. In this contest, we focused mainly on 1) the estimation of the interseismic deformation during the satellites’ observation period, 2) the detection and analysis of the main deformation patterns, and 3) the correlation of the signals to the active tectonic structures. Despite the low convergence rates (~ 1.5-3 mm/yr), Northeast Italy is an active tectonic area, as testified by the instrumental and historical seismicity. The Adria-Eurasia convergence is mainly accommodated by the thrusts and strike-slip faults of the Southeastern Alps and the External Dinarides, located in the northern and northeastern sectors of the study area. The Venetian-Friulian plain and the Adriatic coasts, affected by active subsidence, dominate the southern region. We used the Stanford Method for Persistent Scatterers (StaMPS) applied to Sentinel-1 SAR images acquired along the ascending and descending orbit tracks between 2015 and 2019. Based on a stack of single-master differential interferograms, we detected coherent and temporally stable pixels based on amplitude and phase noise analysis. After applying spatial-temporal filters and additional post-processing operations to refine the measurements, we used Adria-fixed GNSS velocities derived by permanent stations in the study area to calibrate the InSAR velocities. The outcome consists of Line-OF-Sight (LOS) mean ground velocity maps derived by displacement time series along the radar directions for each satellite track. The combination of the LOS datasets yields vertical and east-west velocity maps, which are mostly in agreement with GNSS data and previous geodetic studies. Based on our measurements, we observe a significant positive velocity gradient of 1 mm/yr across the westernmost sector of the Alpine system, suggesting an aseismic motion of the root of the Bassano-Valdobbiadene thrust. The positive vertical gradients (~1 and up to 2 mm/yr) across the Alpine-Dinaric systems in the central and eastern sectors and the eastward motion that increases northeastward (1-2 mm/yr) may be related to the active Alpine-Dinaric thrusts and strike-slip faults. We also suggest that the detected westward motion of the Friulian plain (around Udine) might be attributed to the presence of tectonic structures characterized by transcurrent-transpressive kinematics. Finally, we detect other signals, such as the significant subsidence (2-4 mm/yr) along the coasts and on the southern Venetian-Friulian plain, confirming the correlation between subsidence and the geological setting of the study area. In conclusion, our study confirms the potential of MT-InSAR and GNSS data for the estimation of the surface deformations in response to active tectonics, even in areas characterized by low deformation rates, such as Northeast Italy.In the present study, we exploited the potential of satellite-based geodetic data for detecting and measuring surface displacement in Northeast Italy. In this contest, we focused mainly on 1) the estimation of the interseismic deformation during the satellites’ observation period, 2) the detection and analysis of the main deformation patterns, and 3) the correlation of the signals to the active tectonic structures. Despite the low convergence rates (~ 1.5-3 mm/yr), Northeast Italy is an active tectonic area, as testified by the instrumental and historical seismicity. The Adria-Eurasia convergence is mainly accommodated by the thrusts and strike-slip faults of the Southeastern Alps and the External Dinarides, located in the northern and northeastern sectors of the study area. The Venetian-Friulian plain and the Adriatic coasts, affected by active subsidence, dominate the southern region. We used the Stanford Method for Persistent Scatterers (StaMPS) applied to Sentinel-1 SAR images acquired along the ascending and descending orbit tracks between 2015 and 2019. Based on a stack of single-master differential interferograms, we detected coherent and temporally stable pixels based on amplitude and phase noise analysis. After applying spatial-temporal filters and additional post-processing operations to refine the measurements, we used Adria-fixed GNSS velocities derived by permanent stations in the study area to calibrate the InSAR velocities. The outcome consists of Line-OF-Sight (LOS) mean ground velocity maps derived by displacement time series along the radar directions for each satellite track. The combination of the LOS datasets yields vertical and east-west velocity maps, which are mostly in agreement with GNSS data and previous geodetic studies. Based on our measurements, we observe a significant positive velocity gradient of 1 mm/yr across the westernmost sector of the Alpine system, suggesting an aseismic motion of the root of the Bassano-Valdobbiadene thrust. The positive vertical gradients (~1 and up to 2 mm/yr) across the Alpine-Dinaric systems in the central and eastern sectors and the eastward motion that increases northeastward (1-2 mm/yr) may be related to the active Alpine-Dinaric thrusts and strike-slip faults. We also suggest that the detected westward motion of the Friulian plain (around Udine) might be attributed to the presence of tectonic structures characterized by transcurrent-transpressive kinematics. Finally, we detect other signals, such as the significant subsidence (2-4 mm/yr) along the coasts and on the southern Venetian-Friulian plain, confirming the correlation between subsidence and the geological setting of the study area. In conclusion, our study confirms the potential of MT-InSAR and GNSS data for the estimation of the surface deformations in response to active tectonics, even in areas characterized by low deformation rates, such as Northeast Italy