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Marine applications

Here are given examples of services which BOOST Technologies is able to provide

Oil monitoring

The figure on the left shows typical oil leaks caused by offshore platforms as observed on ERS-2 images on the south west of Danube river Delta.

Such characteristic oil features are frequently observed. Most of the time they are caused by illicit discharges caused by ships. Each time this is possible, source identification should now be performed on standard service operations.

 

Wind field retrieval over Western Mediterranean sea.

SAR imagery has successfully demonstrated its ability to retrieve field of wind speed from fully calibrated radar cross section providing the wind direction is either estimated from the image itself (wind rows, relief shadowing) or given by ancillary data (models, scatterometry).

Reliable information can be retrieved on cell sizes up to 500 meters. The left figure (a) shows an example of wind field retrieved on western Mediterranean sea as estimated on sample ASAR Wide Swath product (ESA courtesy). As a comparison the right figure (b) shows the equivalent result from typical scatterometer resolution.

Note the well-known northwestwardly-oriented Tramontane wind on the upper right corner. Also note the relief shadowing caused by Pyrenees mountain chain and north-westward wind blowing out natural corridor in the vicinity of Tarragona

 

Wind shadows in the lee of hawaiian islands.

SAR imagery has the proper resolution to resolve local sea level winds in complex perturbated atmospheric flows. A spectacular exemple is shown around the Hawaiian islands where north-easterly wind flow is attenuated in the lee of the islands and accelerated by venturi effect in the channels between islands. (ASAR data : copyright ESA 2005)

 

Coastal wave field retrieval

The figure on the left shows the results on a global wave field estimation performed on an ENVISAT Single Look Complex Image.

SAR imagery has the unique ability to monitor wave field in coastal areas. It is also very helpful in understanding phenomena such as bathymetry effect (wavelength shortening, increasing steepness).

Note the diffraction phenomena in the lee of British Channel Isles.

 

SAR features

SAR Azimuth ambiguities

The figure on the left shows typical azimuth ambiguities as observed on ENVISAT IMS product (Single Look Complex data).

Such parasitic echoes arise from finite sampling of azimuth spectrum at the pulse repetition frequency (PRF).

Such phenomena which arise in coastal areas where bright echoes are not uncommon, should not be considered as potential ship position.

                                                                                                                                                                                                

 
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