Our Spatial Planet

Displacement Map from TerraSAR-X

The largest disaster of 2010 so far continues to unfold. Aftershocks are hitting Haiti. Understanding the dynamics of the fault is crucial for planning evacuation and relief operations. TerraSAR-X can image the whole affected area independent of cloud conditions. Using correlation matching DLR extracted the east-west and north-south shifts. The results show upto 2.8m shift along the fault line.

The openlayers project and telascience have started putting together a web portal for the data flowing through from the disaster charter and other sources. EROS imagery shown in the previous post will be available soon.

Haiti UAV Imagery

A significant amount of oil from an oil and gas rig in the Timor Sea has been leaking since the 21st of August 2009.

Apogee has tasked multiple SAR satellites to obtain images over the disaster area since the 29th August. Radar satellites are the most efficient method to monitor large areas, and are well known to delineate the presence of oil on the ocean. This is due to the suppression of capillary waves resulting in a smoother surface where oil is present and a different appearance within the image.

On the 29th August 2009, a Cosmo-Skymed ScanSAR Wide data has been acquired and shows the extent of the oil spill.

Cosmo-skymed data intgrated into Apogee’s Maritime Surveillance Software DEEPBLUE showing the location of the oil spill.

On the 30th August 2009 , a TerraSAR-X ScanSAR image was acquired which clearly shows the extent of the oil spill around the rig.

Containment and recovery operation is underway and oil spill dispersants are being used over the area. The 3 colours on this ScanSAR image are the result of a classification process and show different oil concentration levels on the water.

Classification of oil concentration on the 30th August 2009.

Following up to TerraSAR-X captures detailed radar image of Grafton Floods. Apogee and Infoterra have tasked the TerraSAR-X satellite to acquire a ScanSAR image over the Northern New South Wales coast on the 28th May, to complement the StripMap image acquired on the 24th May. The additional ScanSAR image enhances the information that was available from the single StripMap image. Allowing Apogee to extract more information about the extent of the flooding and how the floods have receded between the two acquisition dates.

This composite below combines the TerraSAR-X StripMap acquired on the 24th of May with the TerraSAR-X ScanSAR image acquired on the 28th of May. The flooding can clearly be seen, where the Red areas show flood level on the 24th of May and the Dark areas show where there is still standing water. Below the composite the seperate StripMap and ScanSAR images show that in this area the water has receded almost completely.

Below the composite TerraSAR-X image shows the flooding extent in Grafton Northern NSW. Red areas in the composite show where there was flooding on the 24th of May, while Dark areas show where there is still flooding. The composite clearly shows that while flooding in the Grafton area has receded, there is still a significant amount of flooding around Grafton. This information is valuable for both managing recovery response during flooding emergency and planning for the emergency response for similar future disasters.

Apogee and Infoterra have tasked TerraSAR-X to acquire a second image over the collapsed Wilkins ice bridge on the 15th April to show ice movements and current as well as the formation of new ice suggesting that the ice debris may not be escaping into the open ocean this year.

This composite below combines the TerraSAR images taken 2 days apart, where the Red ’shadow’ shows the earlier position and the Cyan colour is the later position. The arrows show the result of the drift analysis between the two dates as the direction of currents.

The second image acquired on the 15th April 2009 is shown by itself below and reveals interesting details about the ice structures and reforming new ice.

The image subsets below show a close up of broken ice components. Some of them appear black, probably due to high water content and a smooth surface acting like a mirror. Others show texture suggesting an undulating surface which may have been caused by the  effect of strong winds over time.

Information about ice moisture and texture can be extracted from high resolution data. This ice classification map shows different types of ice. The pink large blocks are the existing ice from the shelf and the other colours represent newly formed ice, which was not present 2 days ago. If the cooling continues, and given the circular nature of the current, the ice may not escape this season.

Wilkins Ice Bridge Collapse

TerraSAR-X ScanSAR over Wilkins Ice Shelf, 13 April 2009.

Subset 1 (see the overview above) shows in great details the western part of the broken ice bridge.

Subset 2 shows in great details the eastern part of the broken ice bridge.