This image combines two Sentinel-1A radar scans from 3 and 15 January 2015 to show ice velocities on outlet glaciers of Greenland’s west coast. Sentinel-1 offers excellent capabilities for observing the velocities of Greenland’s outlet glaciers with unprecedented temporal resolution at complete spatial coverage, extending and enhancing the time series of ice-velocity maps available from previous satellite sensors.

This ‘interferogram’ combines 19 scans by Sentinel-1A’s radar over the San Joaquin Valley in the US state of California. Covering an area of about 30 000 sq km, a number of oil fields are visible (outlined in black). Surface patterns of motion, such as subsidence (red) and uplift (blue), associated with ‘enhanced oil recovery’ operations are observable in the image.

The remote sensing technique known as Interferometric Synthetic Aperture Radar, or InSAR, can be used for a variety of operational applications, including the monitoring of well integrity, reservoir optimisation, identification of undrained compartments and the management of injection activities.

This image was processed by Tele-Rilevamento Europa, which provides measurements of surface deformation with millimetre accuracy using multitemporal satellite radar images. The company has been recognised for its work in the oil and gas sector.

Satellite radar can detect heights in buildings and other structures, such as Saint Peter’s Basilica in the heart of Rome, Italy. Red correlates to higher surfaces (above 60 m) while dark blue depicts lowers surfaces (less than 15 m).

To create this image, radar data from Italy’s Cosmo-SkyMed mission were processed using ‘persistent scatterer pair interferometry’, a technique that can pinpoint surface deformations and heights over wide areas, with millimetre and metre precision, respectively. It typically works best with hard human-made structures or natural terrains excluding forests or cultivated fields, and can trace weak spots in such structures. From this, it is possible to detect deformations of the structures or the ground (typically through subsidence, landslides, earthquakes and volcanic phenomena) or, as in the case of the image, create a 3D reconstruction or urban surface model.

This image was created using the remote sensing technique ‘SAR tomography’ with radar data from the German TerraSAR-X mission acquired between 2009 and 2013. Different coloured points represent different heights.

The point density reaches 1 million points per sq km. Behind each point, the linear deformation rate and the amplitude of thermal expansion from warm weather can also be estimated with millimetre-precision. 

This result was processed using DLR’s Tomographic SAR Processing System, Tomo-GENESIS. 

This image combines two scans from Sentinel-1A’s radar on 3 and 15 October 2014 over Iraq and Eastern Turkey. Colours come from the combined coherence and intensity information and show a wealth of information on the landscape. Assigning certain colours to certain features on the ground requires a more detailed analysis. 

Sentinel-1A radar scans from 23 September and 30 August 2014 were combined to create this ‘interferometric’ image showing surface deformation of a landslide in the municipality of Kåfjord in Troms county, Norway. In the 24 days between the two acquisitions, the ground moved about 1 cm.

Synthetic aperture radar interferometry – or InSAR – is an important technique used by the Norwegian authorities to map rockslide hazards nationwide. The unprecedented coverage offered by the Sentinel-1 mission will significantly increase the value of InSAR data for this purpose. The satellite passes over the same spot on the ground every 12 days.

This radar interferogram combines two acquisition by Sentinel-1A radar from 20 January and 1 February 2015 over the Vestfonna and Austfonna ice caps on the Nordaustlandet Island, Svalbard. A strip of ice-free land sits between the two ice caps. Over the 12-day period, the outlet glaciers flowed at an average of 3 cm per day.

Ten Sentinel-1A radar scans acquired between 7 October 2014 and 12 March 2015 were combined to create this image of ground deformation around the city of Naples, which includes the active volcanic areas of Italy’s Phlegraean Fields – or Campi Flegrei – and the Vesuvius volcano. Dark blue indicates areas that experienced an uplift of about 0.5 cm per month, while red areas show subsidence down to 0.5 per month. The purple square over the city of Naples indicates the location of the calibration point.

These preliminary results were presented at the Fringe Workshop at ESA’s ESRIN centre for Earth observation. INSARAP is a project under ESA’s Scientific Exploitation of Operational Missions (SEOM) programme.

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This image combining two scans by Sentinel-1A’s radar shows that parts of the Pine Island glacier flowed about 100 m (in pink) between 3 March and 15 March 2015. Light blue represents stable ice on either side of the stream.

Pine Island is the largest glacier in the West Antarctic Ice Sheet and one of the fastest ice streams on the continent, with an average of over 4 km per year. About a tenth of the ice sheet drains out to the sea by way of this glacier.

With its all-weather, day and night radar vision, the Sentinel-1 mission is an important tool for monitoring polar regions and the effects that climate change has on ice.