MT-InSAR and Dam Modeling for the Comprehensive Monitoring of an Earth-Fill Dam: The Case of the Benínar Dam (Almería, Spain)

The Benínar Dam, located in Southeastern Spain, is an earth-fill dam that has experienced filtration issues since its construction in 1985. Despite the installation of various monitoring systems, the data collected are sparse and inadequate for the dam’s lifetime. The present research integrates Multi-Temporal Interferometric Synthetic Aperture Radar (MT-InSAR) and dam modeling to validate the monitoring of this dam, opening the way to enhanced integrated monitoring systems. MT-InSAR was proved to be a reliable and continuous monitoring system for dam deformation, surpassing previously installed systems in terms of precision. MT-InSAR allowed the almost-continuous monitoring of this dam since 1992, combining ERS, Envisat, and Sentinel-1A/B data. Line-of-sight (LOS) velocities of settlement in the crest of the dam evolved from maximums of −6 mm/year (1992–2000), −4 mm/year (2002–2010), and −2 mm/year (2015–2021) with median values of −2.6 and −3.0 mm/year in the first periods (ERS and Envisat) and −1.3 mm/year in the Sentinel 1-A/B period. These results are consistent with the maximum admissible modeled deformation from construction, confirming that settlement was more intense in the dam’s early stages and decreased over time. MT-InSAR was also used to integrate the monitoring of the dam basin, including critical slopes, quarries, and infrastructures, such as roads, tracks, and spillways. This study allows us to conclude that MT-InSAR and dam modeling are important elements for the integrated monitoring systems of embankment dams. This conclusion supports the complete integration of MT-InSAR and 3D modeling into the monitoring systems of embankment dams, as they are a key complement to traditional geotechnical monitoring and can overcome the main limitations of topographical monitoringReMoDams project ESP2017-89344-R (AEI/FEDER, UE) from the Spanish Ministry of Economy, Industry and CompetitivenessSIAGUA project PID2021-128123OB-C21PID2021-128123OB-C22MCIN/AEI/10.13039/ 501100011033/FEDER,UEPOAIUJA-2023/2024CEACTEMA from University of Jaén (Spain)RNM-282 research group from the Junta de Andalucía (Spain

Detection of Ground Subsidence in the City of Durrës, Albania, by Persistent Scatterer Interferometry of Sentinel-1 Radar Imagery: Detection of Ground Subsidence in the City of Durrës, Albania, by Persistent Scatterer Interferometry of Sentinel-1 Radar Imagery

Persistent Scatterer Interferometry (PSI) analysis of multi-temporal Sentinel-1 synthetic aperture radar (SAR) imagery was carried out to detect ground displacement in the city of Durrës, Albania. The analyzed interferometric stack consisted of fifty-eight Sentinel-1 images in ascending orbit covering the time period January 2017-December 2018. The results show a zone of ground subsidence with values of up to -30 mm/year that occur within and very close to the boundaries of the reclaimed lands of the Durrës marsh. Rapid urbanization, generally in the form of informal settlements, has taken place in this area in the last twenty years. In the Port of Durrës, a recently constructed breakwater shows high rates of ground settlement up to -30 mm/year, as well. The study is the first application of satellite radar imagery for the detection of ground displacement in the city of Durrës, Albania. Further monitoring is needed to better understand the ground subsidence and ground settlement processes that occur in the city of Durrës

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

Advanced interpretation of land subsidence by validating multi-interferometric SAR data: the case study of the Anthemountas basin (Northern Greece)

The potential of repeat-pass space borne SAR (Synthetic Aperture Radar) interferometry has been exploited to investigate spatial patterns of land subsidence in the Anthemountas basin, in the northern part of Greece. The PSI (Persistent Scatterer Interferometry) approach, based on the processing of long series of SAR acquisitions, has been applied to forty-two images acquired in 1995–2001 by ERS1/2 satellites. Interferometric results have been analysed at a basin scale as support for land motion mapping and at a local scale for the characterisation of ground motion events affecting the village of Perea in the Thermaikos municipality and the "Macedonia" international airport. PSI results revealed a moderate subsidence phenomenon along the wider coastal zone of Anthemountas basin corresponding to intense groundwater extraction. Highest values, exceeding −20 mm yr−1, were measured in the airport area where the thickest sequence of compressible Quaternary sediments occurs. Intense subsidence has been detected also in the Perea village (maximum deformation of −10 to −15 mm yr−1), where a series of fractures, causing damages to both buildings and infrastructure, occurred in 2005–2006

MT-InSAR and Dam Modeling for the Comprehensive Monitoring of an Earth-Fill Dam: The Case of the Benínar Dam (Almería, Spain)

The Benínar Dam, located in Southeastern Spain, is an earth-fill dam that has experienced filtration issues since its construction in 1985. Despite the installation of various monitoring systems, the data collected are sparse and inadequate for the dam’s lifetime. The present research integrates Multi-Temporal Interferometric Synthetic Aperture Radar (MT-InSAR) and dam modeling to validate the monitoring of this dam, opening the way to enhanced integrated monitoring systems. MT-InSAR was proved to be a reliable and continuous monitoring system for dam deformation, surpassing previously installed systems in terms of precision. MT-InSAR allowed the almost-continuous monitoring of this dam since 1992, combining ERS, Envisat, and Sentinel-1A/B data. Line-of-sight (LOS) velocities of settlement in the crest of the dam evolved from maximums of −6 mm/year (1992–2000), −4 mm/year (2002–2010), and −2 mm/year (2015–2021) with median values of −2.6 and −3.0 mm/year in the first periods (ERS and Envisat) and −1.3 mm/year in the Sentinel 1-A/B period. These results are consistent with the maximum admissible modeled deformation from construction, confirming that settlement was more intense in the dam’s early stages and decreased over time. MT-InSAR was also used to integrate the monitoring of the dam basin, including critical slopes, quarries, and infrastructures, such as roads, tracks, and spillways. This study allows us to conclude that MT-InSAR and dam modeling are important elements for the integrated monitoring systems of embankment dams. This conclusion supports the complete integration of MT-InSAR and 3D modeling into the monitoring systems of embankment dams, as they are a key complement to traditional geotechnical monitoring and can overcome the main limitations of topographical monitoring

Calculation of a nighttime-population map based on free data

When the first authoritative data was released, free access was given to registries like the building registry (BBR). However, statistical data like the nighttime-population is still not free. This analysis shows how we can use dasymetric mapping to dis-aggregate municipality population data into BBR housing units, producing an estimated nighttime-population map. The results produced show that the proposed model has a general overrepresentation of the population, but despite that, this free dataset calculated here, should be usable in many cases where an estimate is adequate

The Lost of Semarang Coastal Areas due to Climate Change and Land Subsidence

Semarang is the capital of Central Java Province, located in the northern part of JavaIsland, Indonesia, with an area of about 374 km2 and inhabited by about 1.57 million people. It has been reported for some time that coastline of Semarang is retreated. This backwards movement is mainly due to coastal erosion triggered by climate change effects, land subsidence, and coastal structures jutting to the sea. During the last two decades (1990-2010) the annual rainfall has increased 18.66 mm per year, while the maximum daily storm increased 0.82 mm/year, and the storm intensity increased annually by 0.4 - 0.5 mm/hour. Consequently, the runoff is estimated toincrease by 8% to 30%, and the flooded area increased about 5% to 15% for the next two decades. Based on sea level data recorded in Tanjung Emas Harbor during the period of 1985 up to 2008, it was found the annual relative sea level rise and land subsidence on the station are 5.536 cm/year and 5.165 cm/year consecutively, and the sea level rise is 3.7 mm per year. Interpretation of satellite imagery in 1991 and 2009 showed that 25.6 km of the total 36.6 km is eroded. This erosion has removed the coastal plain area of 1,764.5 ha. This paper is aimed to discribe and discuss the lost of Semarang Coastal Areas and sum up with concluding remarks

Land subsidence in coastal environments: Knowledge advance in the Venice coastland by TerraSAR-X PSI

The use of satellite SAR interferometric methods has significantly improved the monitoring of ground movements over the last decades, thus opening new possibilities for a more accurate interpretation of land subsidence and its driving mechanisms. TerraSAR-X has been extensively used to study land subsidence in the Venice Lagoon, Italy, with the aim of quantifying the natural and anthropogenic causes. In this paper, we review and update the main results achieved by three research projects supported by DLR AOs (German Aerospace Center Announcement of Opportunity) and conducted to test the capability of TerraSAR-X PSI (Persistent Scatterer Interferometry) to detect ground movements in the complex physiographic setting of the Venice transitional coastal environment. The investigations have been focused on the historical center of Venice, the lagoon inlets where the MoSE is under construction, salt marshes, and newly built-up areas in the littoral. PSI on stacks of stripmap TerraSAR-X images covering short- to long-time periods (i.e., the years 2008\u20132009, 2008\u20132011 and 2008\u20132013) has proven particularly effective to measure land subsidence in the Venice coastland. The very high spatial resolution (3 m) and the short repeat time interval (11 days) of the TerraSAR-X acquisitions make it possible to investigate ground movements with a detail unavailable in the past. The interferometric products, properly calibrated, allowed for a millimetric vertical accuracy of the land movements at both the regional and local scales, even for short-term analyses, i.e., spanning one year only. The new picture of the land movement resulted from processing TerraSAR-X images has significantly contributed to update the knowledge on the subsidence process at the Venice coast

Orbital differential SAR interferometry with polarimetric data

Space-borne Synthetic Aperture Radar (SAR) systems have demonstrated great effectiveness to survey wide areas, independently of the weather conditions and the day/night cycle. One of the most exploited applications is Differential SAR Interferometry (DInSAR), and by extension, advanced multi-temporal techniques addressed as Persistent Scatterers Interferometry (PSI). These techniques provide the means to retrieve the displacement on the observed terrain surface. Taking advantage of the high coverage provided by this technology, natural and human induced phenomena may be monitored and detected in order to avoid and prevent hazardous or even catastrophic situations. A good characterization of such events is often related to the density and quality of the information delivered. In many cases, the success in the interpretation of localized surface motion phenomena relies on having as much measurements as possible. Conventional insitu techniques, when used properly, are able to provide reliable measurements. However, they are limited to their localization, and deploy a high number of instruments is not cost effective. The good characterization provided by PSI measurements is limited by the acquisition parameters and the actual scene under monitoring. SAR images sensitivity over the scene depends strongly on the geometric shape and distribution of targets. Historically, satellite SAR sensors had single polarimetric capabilities, so sensitivity over the scene was restricted to a certain antenna configuration. On the contrary, polarimetric acquisitions emit an receive with different antenna configurations, providing sensitivity to different geometries in the scenario. The launch in these later years of several satellites with polarimetric capabilities has triggered its use in several fields of application. The objective of this thesis is to evaluate the use of Polarimetric SAR (PolSAR) data for its application in the PSI framework. The extra information contained in PolSAR datasets is bound to improve the effectiveness of PSI techniques. Obtaining a higher density and quality of motion measurements will ease the detection and interpretation of terrain displacement phenomena.Els Radars d'Obertura Sintètica (SAR) embarcats en satèl·lits han demostrat ser molt efectius per monitoritzar grans àrees, independentment de les condicions atmosfèriques i del cicle dia/nit. L'aplicació més explotada es l'Interferometria Diferencial SAR (DInSAR), i per extensió, les tècniques avançades de processament multi-temporal anomenades Interferometria de Reflectors Persistents (PSI). Aquestes tècniques són capaces de mesurar el desplaçament en superfície del terreny observat. Aprofitant la gran cobertura que s'aconsegueix amb aquesta tecnologia, fenòmens d'origen tant natural com humà poden ser detectats i controlats per evitar i prevenir situacions de perill o fins i tot catastròfiques. La bona caracterització d'aquestes situacions sovint es relaciona tant amb la densitat com en la qualitat de la informació obtinguda. En molts casos, l’èxit en la interpretació de moviments de terreny localitzats depèn de tenir tants punts de mesura com sigui possible. Les tècniques convencionals de mesura in-situ, quan s'usen de forma adequada, són capaces de donar mesures fiables. No obstant, la seva cobertura està limitada a la localització de l'instrument, i la instal·lació d’un gran nombre d'instruments no és una solució econòmica. La bona caracterització de l'àrea mesurada amb tècniques PSI està limitada pels paràmetres d'adquisició i les característiques de la pròpia escena observada. La sensitivitat de les imatges SAR depèn en gran mesura de la distribució i la forma geomètrica dels blancs mesurats. Històricament, els sensors SAR emetien en polarització simple, i per tant la sensitivitat a la escena estava restringida a aquesta configuració específica de la antena. Per altra banda, durant les adquisicions polarimètriques s'emet i es rep en diferents configuracions de l'antena. Això permet tenir sensitivitat a geometries diferents dins la mateixa escena. El llançament aquest últims anys de diferents satèl·lits amb capacitats polarimètriques ha permès el seu ús en diversos camps d'aplicació. L'objectiu d’aquesta tesi és avaluar l'ús de dades polarimètriques SAR (PolSAR) per la seva aplicació en el marc de les tècniques PSI. La informació addicional que contenen els conjunts d’adquisicions PolSAR ha de millorar l'efectivitat de les tècniques PSI. L'obtenció d'una millor densitat i qualitat de les mesures permet una millor detecció i interpretació dels fenòmens de desplaçament superficial del terreny.Postprint (published version