In the case of accidental pollution, CLS has developed a strategy to quickly provide answers on the spill evolution to the end users. Some ancillary information is used to help in understanding the origin of ambiguous slicks on SAR images. CLS is then able to produce a Near Real Time report containing the following details: - Results of the analysis of SAR image
- Synthetic presentation of all detected slicks
- Detailed description of each reported slicks
- Information on the local meteo-oceanic conditions
- Oil drift forecast
- Other information (vessesels)
Oil spill detection report and drift forecast is posted on the Web and may be consulted using any browser. End-users’ notification is done by e-mail, Fax, etc. Results for the Deepwater Horizon caseIn the case of the Deepwater Horizon, CLS was able to quickly acquire the SAR images over the Gulf of Mexico, from whom the following figures below are extracted. One can distinctly see on the figure 1 the state of the spill on the 26th of April. The wind information derived from the SAR image shows on figure 2 the direction and the speed of the wind. One can then observe that a moderate West-North West wind is pushing the oil spill away from the shore. Figure 1 : SAR image from April 26, 2010 - ASAR data Copyright ESA |
Figure 2 : W-NW wind 7-8 m/s |
On the 27th of April 2010, one can still observe the moderate westerly wind pushing oil to the East. Figure 3 : SAR image from April 27, 2010RADARSAT-2 Data and Products © MacDONALD, DETTWILER AND ASSOCIATES LTD. (year of acquisition) – All Rights Reserved |
Figure 4 : W wind 5-6 m/s |
On the 28th of April 2010, wind becomes lower and its direction changes to North-East. Figure 5 : SAR image from April 28, 2010RADARSAT-2 Data and Products © MacDONALD, DETTWILER AND ASSOCIATES LTD. (year of acquisition) – All Rights Reserved |
Figure 6 : W wind 4-5 m/s |
On the 29th of April 2010, a very low wind region is appearing at the east of oil spill location making oil detection more difficult due to low contrast.The oil spill remains North of the Loop Current highlighted by SAR Doppler analysis (see ESA Web Story) : http://www.esa.int/Our_Activities/Observing_the_Earth/Envisat/Gulf_of_Mexico_oil_spill_in_the_Loop_Current ). Figure 7 : SAR image from April 29, 2010ASAR data Copyright ESA |
Figure 8: W wind 2-3 m/s |
Figure 9 : SAR-dervied sea surface current (radial component) image |
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On the 2nd of May 2010, strong South-South East wind is pushing oil towards the shore. The oil spill still remains at the North of the Loop Current. Figure 10 : SAR image from May 2, 2010ASAR data Copyright ESA |
Figure 11 : S-SE wind 12 m/s |
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