Canada’s RADARSAT-1 was the first operational radar-based Earth Observation Satellite. RADARSAT-1 acquired numerous data collections from 1995 to 2013. The historical value of this data is clear as it allows making comparisons using images of the same region acquired over the years: for example, to study climate change effects.
The Canadian Space Agency has recently released over 37 000 RADARSAT-1 images for public use, free of charge; you can download them here. In light of this initiative, we are evaluating the feasibility of opening up more RADARSAT-1 data over Canada and internationally. Please answer the survey before 2019-06-28, by (Clicking here) in order to help us better understand your needs and preferences with respect to RADARSAT-1 data.
Karachi, the largest city of Pakistan received heavy monsoon rain August 30, 2017. The flood in Karachi due to heavy rains is the continuation of the similar monsoon related flooding crisis in the South East Asia region (India, Bangladesh etc.).The Flood map below is derived (subset of Karachi city ) from European Space Agency (ESA)’s Copernicus Program SENTINEL-1 Synthetic Aperture RADAR (SAR) image acquired on September 01, 2017. The green color in the map shows the flooded region.
The total rainfall derived from satellite data (GPM IMERG) for Karachi from August 29-31, 2017 is shown in Figure below:
This post will provide an overview of the basics of Synthetic Aperture RADAR (SAR) and applications. The main topics discussed in the listed documents include: SAR basics, backscatter, geometry, interferometry, polarimetry, SAR data, data acquisition, available data sets/access to data, data analysis tools, future missions and SAR applications. Please do check Part 2 for more details.
What is RADAR? – RAdio Detection And Ranging
What is SAR? – Synthetic Aperture Radar – Synthetic Aperture Radar (SAR) is an active remote sensing technology that uses microwave energy to illuminate the surface. The system records the elapsed timeand energy of the return pulse received by the antenna (PDF).
The Canada Centre for Mapping and Earth Observation (CCMEO) is considered an international leader in the development and use of synthetic aperture radar or SAR sensors. From space, SAR can image the Earth’s surface through clouds and in total darkness. This makes it a tremendously useful sensor for monitoring Canada’s changing landmass and coastal zones. CCMEO scientists have worked with the Canadian Space Agency in the development of both RADARSAT 1 and RADARSAT 2 satellite missions. Their research has led to improved data quality through enhanced sensor design and post-launch calibration and validation activities.
This training manual introduces and explains Interferometric Synthetic Aperture Radar (InSAR), including applications for data from the Envisat ASAR sensor and how to combine Envisat and ERS images to produce interferograms and differential interferograms.
Active Microwave Remote Sensing provides cloud penetration and day-night imaging capability. These unique characteristics of C-band (5.35GHz) Synthetic Aperture Radar enable applications in agriculture, particularly paddy monitoring in kharif season and management of natural disasters like flood and cyclone.
Terra SAR-X / TanDEM-X
Launched in 2007/10, X-band quad polirzation, DLR/Astrium, Germany
Terra SAR-X (TSX) mission overview, spacecraft, references (Link) (Link to documents)
JAXA conducted research and development activities for ALOS-2 to improve wide and high-resolution observation technologies developed for ALOS in order to further fulfill social needs. These social needs include: 1) Disaster monitoring of damage areas, both in considerable detail, and when these areas may be large 2) Continuous updating of data archives related to national land and infrastructure information 3) Effective monitoring of cultivated areas 4) Global monitoring of tropical rain forests to identify carbon sinks.
Launched in 2007/10, 4 Satellites X-band dual polirzation, ASI/Italy
COSMO SkyMed offers high resolution X‐Band SAR (synthetic aperture radar) images. Despite its enormous potential, research investigating the possible uses in archaeology is still very scarce, especially of one which works solely with single date analysis starting with a single SAR scene (PDF).
Launched in 2013, S-band (HH or VV) polarization CRESDA/CAST/NRSCC, China
HJ-1A/B/C corresponding to environment and disaster monitoring and forecasting small satellite constellation A/B/C include two optical satellites – HJ-1A/B and one radar satellite HJ-1C, which can carry out large-scale, all-weather and 24h dynamic monitoring for ecological environment and disaster (Link).
Launched in 2014, X-band quad polarization, Ministry of Defense, Spain
PAZ is a Spanish radar technology satellite designed to address not only security and defense requirements, but also others of civilian nature. It is capable of daily taking more than 100 images of up to 25 cm resolution, both day and night, and independently of weather conditions (Link).
Launched in 2013, X-band dual polarization, KARI, Korea
The Argentina National Space Activities Commission (CONAE) launched a new Earth observationsatellite that will support disaster management efforts. SAOCOM 1A is the first of a constellation of two radar satellites. The remote sensing mission aims to provide timely information for disaster management as well as monitoring services for agriculture, mining and ocean applications.
The launch of the first dual-frequency synthetic aperture radar (SAR). The data collected by the L-band (produced by NASA) and S-band (produced by ISRO) SAR systems aboard the NISAR satellite and processed into cloud-free, ultra-sharp imagery will facilitate cutting-edge research into some of the planet’s most complex processes, including ecosystem disturbances, ice-sheet dynamics, earthquakes, tsunamis, volcanoes, and landslides.
RADARSAT Constellation Mission (RCM)
Will launch in 2019 three satellites, C-band quad compact polirzation, Canadian Space Agency (CSA) (Link)
ESA is pleased to announce that SAR data from the ERS-1 and the ERS-2 missions have been made available for direct download via the (A)SAR On-The-Fly (OTF) service.
With this release, users now have access to (A)SAR level 1 products from both ERS missions and from Envisat, covering Image Mode (IMS, IMP), Wide Swath (WSS) and Alternating Polarisation (APP, APS). All data are delivered as standard scenes in Envisat format.
The evolution of the Sentinel Collaborative Ground Segment
12 January 2017
ESA and its Member States created the Sentinel Collaborative Ground Segment (CollGS) to further enhance the Sentinel missions exploitation in various areas. Today, the cooperation is also open to all European countries and Copernicus Participating States.
Besides the challenging task of building and launching a satellite, a key indicator of the success of an Earth observation mission relies on ensuring that the data gathered are of good quality and made easily available to users.
The Sentinel Collaborative Ground Segment complements the Copernicus Ground Segment. This entails additional elements for specialised solutions in different technological areas, such as data acquisition, complementary production and dissemination.
But what does the CollGS do, exactly?
National entities can build-up their own mirror data archive and base operational services on Sentinel data. Participating countries then redistribute the Sentinel data and/or value added products from their “mirror sites”, to institutional, commercial and science users.
Many mirror sites in place are now also adding hosted processing to their services.
If technically required to meet data timeliness obligations, local ground stations are configured to listen-in as Sentinel data is downlinked to core ground stations. This allows for quasi-real time product generation as, for instance, in supporting marine surveillance activities in the Baltic Sea.
Furthermore, in the frame of the CollGS, national initiatives carry out the development of innovative tools and applications.
Canada, which is an associate ESA Member State, operates extremely important land and maritime monitoring activities, with C-CORE and other organisations. Having established a CollGS agreement, they can access the Sentinel products via a data hub operated by ESA and dedicated to collaborative partners.
Shahid Khurshid, Physical Scientist at Meteorological Service of Canada, and Matt Arkett, Acting Manager of Earth Observation and Geomatics, at Environment and Climate Change Canada, said: “Environment and Climate Change Canada’s Operational National SAR Winds (NSW) system provides near real-time delivery of marine wind measurements derived from spaceborne synthetic aperture Radars (SAR) to support marine forecasters & other applications.
“The programme has been operational since 2013, ingesting SAR data from the RADARSAT-1 and RADARSAT-2 missions. The NSW system began to generate operational surface wind maps using Sentinel-1A data in April 2016 and Sentinel-1B in September 2016. “Access to Sentinel-1 data has significantly increased the temporal and spatial frequency of marine wind speed information being delivered to our operational marine forecasters.