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:
ESA’s Climate Change Initiative in Glaciers_CCI Project, a team of researchers are using Copernicus Sentinel-1 SAR data with other optical data to monitor glaciers from space. The Negribreen glacier surge has been captured and shown in the animated gif (credit: ESA)
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.
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 time an d energy of the return pulse received by the antenna.
Synthetic Aperature Radar (SAR) Tutorials
- A Tutorial on Synthetic Aperture RADAR – ESA (PDF ) (PDF) (Radiometric Calibration of SAR Image)
- 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.
- Synthetic Aperture RADARs Imaging Basics (PDF)
- NOAA SAR Manual (PDF)
- Synthetic-aperture imaging from high-Doppler-resolution measurements (PDF)
- A Mathematical Tutorial on Synthetic Aperture RADAR (PDF)
- Remote sensed ground control points with TerraSAR-X and TanDEM-X (PDF)
Synthetic Aperature Radar (SAR) Applications
- Infrastructure Monitoring with Spaceborne SAR Sensors (Link)
- Soil Moisture Measurements by SAR (PDF)
- Marine applications: Sea Ice (Link), Marine Winds (PDF), Oil Pollution (PDF)
- Land deformation (Link)
- Flood Mapping (PDF) (PDF)
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.
Processing and download of the generated “standard scene” Level 1 products is performed directly through the EOLI-SA user interface. A user manual and FAQ page are available to get started.
Source: ERS SAR data available via ESA On-The-Fly service – Content – Earth Online – ESA