Brief communication: Hurricane Dorian: automated near-real-time mapping of the “unprecedented” flooding in the Bahamas using synthetic aperture radar

Abstract. In this communication, we present application of the automated near-real-time (NRT) system called RAdar-Produced Inundation Diary (RAPID) to European Space Agency Sentinel-1 synthetic aperture radar (SAR) images to produce flooding maps for Hurricane Dorian in the northern Bahamas. RAPID maps, released 2 d after the event, show that coastal flooding in the Bahamas reached areas located more than 10 km inland, covering more than 3000 km2 of continental area. RAPID flood estimates from subsequent SAR images show the recession of the flood across the islands and present high agreement scores when compared to Copernicus Emergency Management Service (Copernicus EMS) estimates.

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Brief communication: Hurricane Dorian: automated near-real-time mapping of the unprecedented flooding on the Bahamas using SAR

10.5194/nhess-2019-312 ◽

2019 ◽

Cited By ~ 1

Author(s):

Diego Cerrai ◽

Qing Yang ◽

Xinyi Shen ◽

Marika Koukoula ◽

Emmanouil N. Anagnostou

Keyword(s):

Real Time ◽

Disaster Response ◽

European Space Agency ◽

Sar Images ◽

The Bahamas ◽

In Situ Data ◽

Space Agency ◽

Continental Area ◽

Flooded Areas

Abstract. Lack of real-time, in situ data on the extent of flooding in many parts of the world can hinder efficient disaster response. With the advent of satellite-based synthetic aperture radar (SAR) sensors, we can deploy techniques to identify flooded areas worldwide while storms are occurring. In this communication, we present an automated near-real-time (NRT) system called RAdar-Produced Inundation Diary (RAPID), applying it to European Space Agency Sentinel-1 SAR images to produce flooding maps for Hurricane Dorian in the northern Bahamas. Images from RAPID released two days after the event show coastal flooding in the Bahamas reached areas located more than 10 km inland, covering more than 3,000 km2 of continental area. RAPID flood estimates from subsequent SAR images show the recession of the flood across the islands.

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The Use of Sentinel-1 Synthetic Aperture Radar (SAR) Images and Open-Source Software for Cultural Heritage: An Example from Paphos Area in Cyprus for Mapping Landscape Changes after a 5.6 Magnitude Earthquake

Remote Sensing ◽

10.3390/rs11151766 ◽

2019 ◽

Vol 11 (15) ◽

pp. 1766 ◽

Cited By ~ 8

Author(s):

Marios Tzouvaras ◽

Dimitris Kouhartsiouk ◽

Athos Agapiou ◽

Chris Danezis ◽

Diofantos G. Hadjimitsis

Keyword(s):

Cultural Heritage ◽

Synthetic Aperture Radar ◽

Open Source ◽

European Space Agency ◽

Synthetic Aperture ◽

Active Sensors ◽

Heritage Sites ◽

Space Agency ◽

World Heritage List ◽

Aperture Radar

Active satellite remote sensors have emerged in the last years in the field of archaeology, providing new tools for monitoring extensive cultural heritage landscapes and areas. These active sensors, namely synthetic aperture radar (SAR) satellites, provide systematic datasets for mapping land movements triggered from earthquakes, landslides, and so on. Copernicus, the European program for monitoring the environment, provides continuous radar datasets through the Sentinel-1 mission with an almost worldwide coverage. This paper aims to demonstrate how the use of open-access and freely distributed datasets such as those under the Copernicus umbrella, along with the exploitation of open-source radar processing software, namely the sentinel applications platform (SNAP) and SNAPHU tools, provided respectively by the European Space Agency (ESA) and the University of Stanford, can be used to extract an SAR interferogram in the wider area of Paphos, located in the western part of Cyprus. The city includes various heritage sites and monuments, some of them already included in the UNESCO World Heritage list. The interferogram was prepared to study the effects of an earthquake to the buildings and sites of the area. The earthquake of a 5.6 magnitude on the Richter scale was triggered on 15 April 2015 and was strongly felt throughout the whole island. The interferogram results were based on Differential Synthetic Aperture Radar Interferometry (D-InSAR) methodology, finding a maximum uplift of 74 mm and a maximum subsidence of 31 mm. The overall process and methodology are presented in this paper.

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Quantification of oil lost from tanker vessel using space borne radar datasets - Case study of Haldia port oil spill, July 2018.

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-2021.1.686884 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

S.J Prasad ◽

T.M. Balakrishnan Nair

Keyword(s):

Synthetic Aperture Radar ◽

Oil Spill ◽

European Space Agency ◽

Fuel Oil ◽

Synthetic Aperture ◽

Synthetic Aperture Radar Data ◽

Space Agency ◽

Sar Data ◽

Spilled Oil ◽

Aperture Radar

Abstract 686884 Determining the spilled volume of the marine oil pollutant is an essential requisite for the oil spill modellers and the responders. Generally, the mass of the spilled pollutant is computed from the total quantity and the remaining quantity of the storage tank of the distressed vessel. A method to estimate the quantity of the spilled oil pollutant using the space -borne synthetic aperture radar dataset is elaborated here. The synthetic aperture radar data, its ability to penetrate cloud cover, irrespective of weather conditions, has been widely used to detect the signature of spilt oil. SAR data available from European Space Agency and Canadian Space Agency were used to detect the oil spills as they are proved to be appropriate for oil spill detection. Minor oil spill occured off Haldia Port, off Kolkata from SSL tanker vessel on 14 July 2018. The geographical location of the distressed vessel is 88.775 ′E, 21.441 ′N. The zone of the vessel distress was monitored for oil slicks. The acquisition plan of the Radar satellite Sentinel -1A was obtained from European Space Agency. As per that, the pass of the Sentinel -1A was available on 15 July 2018 and 17 July 2018 for the region of study. The Synthetic Aperture Radar (SAR) datasets were obtained from Sentinel -1A as per their availability. Those datasets were processed using Sentinel Application Platform (SNAP) tool box. The SAR data is subjected to terrain correction, which automatically reprojects the radar scene. The next stage is performing radiometric calibration, which converts the amplitude into intensity values. The radar reflectance values are converted to Sigma0 intensity values in Sentinel tool box. This Sigma0 values were wrote in netcdf format for identifying the oil slicks. The pixels of lesser intensity values are identified and are interpreted for oil slicks. The zone of the oil slicks in the radar scene are considered as irregular polygons. The area of those polygons were computed. Later the volume of the spilled oil is computed using the thickness of the spilled oil pollutant. Finally the mass of the pollutant is computed. It was collectively estimated from the SAR datasets, that, 33 Tons of Fuel oil was lost from SSL vessel that sank off Haldia Port. This paper elaborates in detail about the method of processing SAR dataset and estimating the quantity of oil lost from the vessel using SAR datasets.

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Estimation of Velocity of the Polar Record Glacier, Antarctica Using Synthetic Aperture Radar (SAR)

Proceedings ◽

10.3390/ecrs-2-05145 ◽

2018 ◽

Vol 2 (7) ◽

pp. 332

Author(s):

Prashant H. Pandit ◽

Shridhar D. Jawak ◽

Alvarinho J. Luis

Keyword(s):

Synthetic Aperture Radar ◽

European Space Agency ◽

Velocity Estimation ◽

Synthetic Aperture ◽

Persistent Scatterer Interferometry ◽

Synthetic Aperture Radar Interferometry ◽

Space Agency ◽

Persistent Scatterer ◽

Glacier Velocity ◽

Aperture Radar

The ice flow velocity is a critical variable in understanding the glacier dynamics. The Synthetic Aperture Radar Interferometry (InSAR) is a robust technique to monitor Earth’s surface mainly to measure its topography and deformation. The phase information from two or more interferogram further helps to extract information about the height and displacement of the surface. We used this technique to derive glacier velocity for Polar Record Glacier (PRG), East Antarctica, using Sentinel-1 Single Look Complex images that were captured in Interferometric Wide mode. For velocity estimation, Persistent Scatterer interferometry (PS-InSAR) method was applied, which uses the time coherent of permanent pixel of master images and correlates to the same pixel of the slave image to get displacement by tracking the intensity of those pixels. C-band sensor of European Space Agency, Sentinel-1A, and 1B data were used in this study. Estimated average velocity of the PRG is found to be approximately ≈400 ma−1, which varied from ≈100 to ≈700 ma−1. We also found that PRG moves at ≈700 and 200 ma−1 in the lower part and the upper inland area, respectively.

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A Preliminary Damage Assessment Using Dual Path Synthetic Aperture Radar Analysis for the M 6.4 Petrinja Earthquake (2020), Croatia

Remote Sensing ◽

10.3390/rs13122267 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2267

Author(s):

Sadra Karimzadeh ◽

Masashi Matsuoka

Keyword(s):

Synthetic Aperture Radar ◽

Sar Interferometry ◽

Synthetic Aperture ◽

Management Service ◽

Ground Displacement ◽

Sar Images ◽

Damage Mapping ◽

Surrounding Areas ◽

The Town ◽

Aperture Radar

On 29 December 2020, an earthquake with a magnitude of M 6.4 hit the central part of Croatia. The earthquake resulted in casualties and damaged buildings in the town of Petrinja (~6 km away from the epicenter) and surrounding areas. This study aims to characterize ground displacement and to estimate the location of damaged areas following the Petrinja earthquake using six synthetic aperture radar (SAR) images (C-band) acquired from both ascending and descending orbits of the Sentinel-1 mission. Phase information from both the ascending (Sentinel-1A) and descending (Sentinel-1B) datasets, acquired from SAR interferometry (InSAR), is used for estimation of ground displacement. For damage mapping, we use histogram information along with the RGB method to visualize the affected areas. In sparsely damaged areas, we also propose a method based on multivariate alteration detection (MAD) and naive Bayes (NB), in which pre-seismic and co-seismic coherence maps and geocoded intensity maps are the main independent variables, together with elevation and displacement maps. For training, approximately 70% of the data are employed and the rest of the data are used for validation. The results show that, despite the limitations of C-band SAR images in densely vegetated areas, the overall accuracy of MAD+NB is ~68% compared with the results from the Copernicus Emergency Management Service (CEMS).

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Glacier Monitoring Using Frequency Domain Offset Tracking Applied to Sentinel-1 Images: A Product Performance Comparison

Remote Sensing ◽

10.3390/rs11111322 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1322 ◽

Cited By ~ 2

Author(s):

Donato Amitrano ◽

Raffaella Guida ◽

Gerardo Di Martino ◽

Antonio Iodice

Keyword(s):

High Resolution ◽

Synthetic Aperture Radar ◽

European Space Agency ◽

Performance Comparison ◽

Synthetic Aperture ◽

Space Agency ◽

Medium Resolution ◽

Offset Tracking ◽

Wide Swath ◽

Aperture Radar

The Sentinel-1 mission has now reached its maturity, and is acquiring high-quality images with a high revisit time, allowing for effective continuous monitoring of our rapidly changing planet. The purpose of this work is to assess the performance of the different synthetic aperture radar products made available by the European Space Agency through the Sentinels Data Hub against glacier displacement monitoring with offset tracking methodology. In particular, four classes of products have been tested: the medium resolution ground range detected, the high-resolution ground range detected, acquired in both interferometric wide and extra-wide swath, and the single look complex. The first are detected pre-processed images with about 40, 25, and 10-m pixel spacing, respectively. The last category, the most commonly adopted for the application at issue, represents the standard coherent synthetic aperture radar product, delivered in unprocessed focused complex format with pixel spacing ranging from 14 to 20 m in azimuth and from approximately 2 to 6 m in range, depending on the acquisition area and mode. Tests have been performed on data acquired over four glaciers, i.e., the Petermann Glacier, the Nioghalvfjerdsfjorden, the Jackobshavn Isbræ and the Thwaites Glacier. They revealed that the displacements estimated using interferometric wide swath single look complex and high-resolution ground range detected products are fully comparable, even at computational level. As a result, considering the differences in memory consumption and pre-processing requirements presented by these two kinds of product, detected formats should be preferred for facing the application.

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KLASIFIKASI SAWAH DAN NON-SAWAH DENGAN METODE RANDOM FOREST PADA CITRA SAR SENTINEL-1 (Studi Kasus di Kecamatan Kediri, Kabupaten Tabanan, Bali)

Seminar Nasional Geomatika ◽

10.24895/sng.2020.0-0.1140 ◽

2021 ◽

pp. 245

Author(s):

I Made Oka Guna Antara ◽

Tati Budi Kusmiyarti ◽

R. Suyarto ◽

Wiyanti Wiyanti

Keyword(s):

Random Forest ◽

Synthetic Aperture Radar ◽

European Space Agency ◽

Training Data ◽

Synthetic Aperture ◽

Space Agency ◽

Level 1 ◽

Aperture Radar

Pemanfaatan teknologi penginderaan jauh dalam bidang pemetaan telah lama dikenal. Data penginderaan jauh menjadi salah satu sumber data untuk pemetaan, yang memberikan informasi rupa bumi, seperti Kawasan pemukiman, Kawasan hutan, Kawasan pertanian dan lain sebagainya. Salah satu jenis data penginderaan jauh adalah citra Synthetic Aperture Radar (SAR), SAR memancarkan gelombang elektromagnetik untuk mendapatkan informasi dari target/rupa bumi. Citra SAR memiliki kelebihan tidak terpengaruh awan, cuaca (hujan dengan intensitas ringan), dan dapat bekerja sepanjang hari serta malam, dibandingkan dengan citra optik. Citra SAR dengan metode komposit RGB dual polarimetric multiple menggunakan aplikasi SNAP Toolbox dari European Space Agency (ESA) dapat dimanfaatkan untuk membedakan lokasi persawahan dengan bukan sawah, perbedaan backscatter atau nilai reflektan digunakan untuk mengetahuinya. Penelitian lebih lanjut menggunakan metode klasifikasi non parametrik Random Forest, dengan membuat kelas menjadi 2, yaitu sawah dan non sawah, ke-2 kelas digunakan sebagai training data untuk metode tersebut. Data yang digunakan adalah citra satelit Sentinel-1 pada tanggal 30 Maret 2020 dengan mode IW Level-1 GRD Ascending direction beresolusi 20x22 m dan polarisasi ganda (VH dan VV) di Kecamatan Kediri, Kabupaten Tabanan, Provinsi Bali. Dari hasil penelitian diperoleh akurasi 96,90%.

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DINÂMICA DA COBERTURA E USO DA TERRA NA BACIA HIDROGRÁFICA DO RIO ARAGUARI (AMAPÁ, AMAZÔNIA, BRASIL)

InterEspaço Revista de Geografia e Interdisciplinaridade ◽

10.18764/2446-6549.e202003 ◽

2020 ◽

Vol 5 (19) ◽

pp. 202003

Author(s):

Alan Nunes Araújo ◽

Maria Lúcia Brito da Cruz ◽

Christian Nunes da Silva ◽

Amintas Nazareth Rossete

Keyword(s):

Land Use ◽

Synthetic Aperture Radar ◽

Vegetation Cover ◽

European Space Agency ◽

Climatic Conditions ◽

Synthetic Aperture ◽

Study Region ◽

Hydrographic Basin ◽

Space Agency ◽

Aperture Radar

DYNAMICS OF COVERAGE AND LAND USE IN THE HYDROGRAPHIC BASIN OF RIO ARAGUARI (AMAPÁ, AMAZÔNIA, BRAZIL)DYNAMIQUE DE LA COUVERTURE ET DE L'UTILISATION DES TERRES DANS LE BASSIN HYDROGRAPHIQUE DE LA RIVIÈRE ARAGUARI (AMAPÁ, AMAZONE, BRÉSIL)RESUMOO objetivo deste trabalho é compreender as relações mútuas e dialéticas entre a sociedade e a natureza, refletidas na paisagem e materializadas na dinâmica do uso da terra e da cobertura vegetal da bacia hidrográfica do rio Araguari (Amapá, Amazônia, Brasil), a partir de uma visão integrada. Como recurso metodológico para os anos de 1995 e 2005, foram manipuladas imagens do sensor TM, acoplado ao satélite Landsat 5, das bandas espectrais 5 (red), 4 (blue) e 3 (green), com resolução espacial de 30 metros. Para o ano de 2017, foram manipuladas imagens dos sensores Sentinel 2B, visto que, para a região de estudo, estes são os mais indicados, pois são equipados com sensores C-SAR (Radar de Abertura Sintética), que coletam imagens, mesmo em condições climáticas adversas (em presença de nuvens, principalmente), pertencentes ao programa Copernicus de observação da Terra, da Agência Espacial Europeia (ESA). A classificação de uso e de cobertura do solo foi realizada por meio do programa eCognition 9.0, com base nas análises tipológicas, realizadas pelo reconhecimento em campo da cobertura vegetal e da análise da paisagem, e pelo processo de segmentação, correspondente à área da bacia hidrográfica em estudo, utilizando classificação orientada ao objeto. Os resultados demonstraram que a bacia hidrográfica do rio Araguari apresenta grandes transformações desde o ano de 1995, principalmente no médio e baixo curso, reflexos dos intensos processos de exploração de seus recursos naturais.Palavras-chave: Rio Araguari; Amapá; Exploração; Recursos Naturais; Amazônia.ABSTRACTThe objective of this work is to understand the mutual and dialectical relations between society and nature, reflected in the landscape and materialized in the dynamics of land use and vegetation cover in the hydrographic basin of the Araguari River (Amapá, Amazonia, Brazil), from an integrated view. As a methodological resource for the years 1995 and 2005, images were manipulated from the TM sensor, coupled to the Landsat 5 satellite, of the spectral bands 5 (red), 4 (blue) and 3 (green), with spatial resolution of 30 meters. For the year 2017, images from the Sentinel 2B sensors were manipulated, since, for the study region, these are the most suitable, as they are equipped with C-SAR (Synthetic Aperture Radar) sensors, which collect images, even in adverse climatic conditions (mainly in the presence of clouds), belonging to the European Space Agency (ESA) Copernicus Earth Observation program. The classification of land use and cover was carried out using the eCognition 9.0 program, based on typological analyzes, carried out by field recognition of vegetation cover and landscape analysis, and by the segmentation process, corresponding to the area of the hydrographic basin under study, using object-oriented classification. The results showed that the hydrographic basin of the Araguari River has undergone major changes since 1995, mainly in the medium and low course, reflecting the intense processes of exploitation of its natural resources.Keywords: Araguari River; Amapá; Exploration; Natural Resources; Amazon.RÉSUMÉL'objectif de ce travail est de comprendre les relations mutuelles et dialectiques entre la société et la nature, reflétées dans le paysage et matérialisées dans la dynamique de l'utilisation des terres et du couvert végétal dans le bassin hydrographique de la rivière Araguari (Amapá, Amazonie, Brésil), la d'une vue intégrée. En tant que ressource méthodologique pour les années 1995 et 2005, les images ont été manipulées à partir du capteur TM, couplé au satellite Landsat 5, des bandes spectrales 5 (rouge), 4 (bleu) et 3 (vert), avec une résolution spatiale de 30 mètres. Pour l'année 2017, les images des capteurs Sentinel 2B ont été manipulées, car, pour la région d'étude, ce sont les plus adaptées, car elles sont équipées de capteurs C-SAR (Synthetic Aperture Radar), qui collectent des images, même dans conditions climatiques défavorables (principalement en présence de nuages), appartenant au programme Copernicus d'observation de la Terre de l'Agence spatiale européenne (ESA). La classification de l'utilisation et de la couverture des terres a été réalisée à l'aide du programme eCognition 9.0, basée sur des analyses typologiques, réalisées par reconnaissance sur le terrain de la couverture végétale et analyse du paysage, et par le processus de segmentation, correspondant à la superficie du bassin hydrographique à l'étude, utilisant la classification orientée objet. Les résultats ont montré que le bassin hydrographique de la rivière Araguari a subi des changements majeurs depuis 1995, principalement à moyen et bas cours, reflétant les processus intenses d'exploitation de ses ressources naturelles.Mots-clés: Rivière Araguari; Amapá; Exploration; Ressources Naturelles; Amazone.

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