Galicia, Spain (From MSNBC) - A crippled tanker carrying more than 20 million gallons (around 67,000 tons) of oil split in half off the northwest coast of Spain on 19 November 2002, threatening one of the worst environmental disasters in history.

The rear section of the Prestige sunk early in the day, taking many of the oil tanks with it. Should the tanks leak, the resulting spill would be more than twice the size of that caused by the 1989 Exxon Valdez accident, warned the World Wildlife Federation.

Read more from this article, and two other news stories.

ESA supplies satellite imagery on Spanish oil spill under International Charter on Space and Major Disasters, Italy, 9 December 2002

To support relief agencies with space data, ESA has been providing satellite images almost daily since 17 November from its ERS and Envisat spacecraft in support of relief efforts in the wake of the oil spill off the Spanish coast.

ESA regularly supplies SAR images to the involved authorities in Spain, Portugal and France. The images were initially requested by the European Commission, which activated the International Charter on Space and Major Disasters, on 14 November. Imagery has been, and will continue to be sent to the authorised user, the EC's Monitoring and Information Centre, and forwarded to national authorities.

The Charter is an international endeavour to bring satellite technology at the service of rescue authorities and other civil protection agencies in cases of natural or man-made disasters. Under the agreement, ESA, along with CNES, the Canadian Space Agency, the Indian Space Research Organization, and the US National Oceanic and Atmospheric Administration, have agreed to contribute with their satellite imagery upon request from authorised users, usually the civil protection organization from the country of a Charter member.

A 24-hour operator - located at ESRIN, Frascati - receives incoming requests and passes the information along to an emergency on-call officer provided by each agency on a weekly rotation, who prepares an archive and acquisition plan using available space resources. The case is then followed by a project manager, who, in the case of the oil spill from the tanker "Prestige," was assigned to CNES, which coordinated the satellite acquisitions and performed the initial imagery interpretation before passing it along to the authorised user.

The extent of the oil spill was clearly visible on an acquisition from Envisat ASAR instrument on 17 November and on a RADARSAT-1 image on 18 November. After 19 November, the sea conditions turned very bad and prevented obvious detection of the oil slicks. However, suspected oil slicks around the Spanish coast appear on the images acquired on 2 and 3 December.

Image acquisitions of the affected area will continue and will be forwarded to the appropriate civil agencies. ESA has given full priority to data acquisition of the affected area, it is important to understand that the repeat cycle of the satellite does not allow having an image every day. The fact that the Envisat satellite is still in the commissioning phase introduces some delays in the availability of the processed images.

Satellite Planning

The details of this special ERS SAR and Envisat ASAR planning are available.

The images below have been processed by the Earth Watching team during the period of the disaster response. All the images have been delivered to the Spanish, Portuguese and French authorities.

Click on the thumbnail images to view larger versions.

	An Envisat ASAR Wide Swath image acquisition was scheduled (in emergency) for 17 November 2002. The data were acquired in Matera (Italy) and the corresponding image was generated on 20 November at ESRIN in Italy. The image covers an area of 400x300 KM. The two images below show magnified views of this image. The oil slick released by the tanker is visible as a black streak across the images. The tanker itself is visible as a white dot at the bottom-left of the main slick (bottom-left of the image). The black areas along the Spanish coast near the town of Vigo are due to calm waters and not to oil.
ERS SAR acquisition of 2 December at night-time (orbit 39836). Possible oil slicks are visible in the image. The image is located west of Galicia where the ship sank.	Envisat ASAR acquisition of 2 December (orbit 3963). Possible oil slicks are visible in the image. A magnified view is available that examines one potential oil slick.
ERS SAR acquisition of 3 December at night-time (orbit 39824). Possible oil slicks, but probably it is only sea current. The two coastal towns are Aviles and Gijon (Asturias region).	Envisat ASAR acquisition of 3 December at night-time (orbit 3970). In this quick look image no spills are visible.
ERS SAR acquisition of 6 December at night-time (orbit 39935). Possible oil slicks are visible in the upper right part of the image. The two coastal towns are Aviles and Gijon (Asturias region).	Envisat ASAR acquisition of 6 December at night-time (orbit 4020). Note: the area covered by the ERS image is mainly the left part (lower portion). Possible oil slicks are visible in the central part of the image (partially covered by the left ERS image).
ERS SAR acquisition of 9 December (orbit 39928). No oil slicks are visible in the image.	Envisat ASAR acquisition of 9 December (orbit 4056). Note: the large black area (around 200 x 200 km) visible on the left of the image is due to atmospheric phenomena and not to oil.
	Envisat ASAR acquisition of 9 December at night-time (orbit 4063). An oil slick may be visible, but it could be an area of calm water caused by no wind. The coastal town on the right is Santander.
	ERS SAR acquisition of 12 December (orbit 39971). Possible oil slicks, but the wind is very strong. The "cushion" effect is due to clouds over water.
	ERS SAR acquisition of 12 December night (orbit 39978). No oil slicks detected (the black areas along the coast are calm water).
	Envisat ASAR acquisition of 13 December (orbit 4113). The image covers the Spanish and French coasts.
ERS SAR acquisition of 16 December (orbit 40028). High probability of oil slicks. The town along the coast (cluster of bright dots) is Santander (Cantabria region).	Envisat ASAR acquisition of 16 December night (orbit 4156). High probability of oil slicks.
ERS SAR acquisition of 19 December (orbit 40071). Possible oil slicks. The town along the coast (cluster of bright dots on the left) is Gijon (Asturias region).	Envisat ASAR acquisition of 19 December night (orbit 4206). Possible oil slicks. Browse image, covering the Spanish and French coasts.
	ERS SAR acquisition of 22 December (orbit 40114). The rightmost dark area is with high probability an oil slick. The image is over the Galicia and Asturias regions. See tracking map for this acquisition.
	Envisat ASAR acquisition of 25 December at night-time (orbit 4292). High possible oil slicks. The image covers the Asturias and Cantabria regions.
	Envisat ASAR acquisition of 26 December (orbit 4299). The dark area is with high probability oil slicks. The image covers the coast of the Spanish and French (Aquitaine) coasts.
	Envisat ASAR acquisition of 31 December at night-time (orbit 4378). High possible oil slicks. The image covers the Galicia and Asturias regions.
	ERS SAR acquisition of 01 January 2003 (orbit 40257 frame 2727). The rightmost dark areas are with high probability oil slicks. The image covers the coast of the Cantabria region. See tracking map for this acquisition.
	Envisat ASAR acquisition of 03 January at night-time (orbit 4421). High possible oil slicks. The image covers the coast south of the Galicia region.
	ERS SAR acquisition of 04 January 2003 (orbit 40307 frame 891). The rightmost dark areas are with high probability oil slicks. The image covers the north coast of the Cantabria region. See tracking map for this acquisition.
	Envisat ASAR acquisition of 06 January at night-time (orbit 4464). Possible oil slicks. The image covers the coast south of the Galicia region.
ERS SAR acquisition of 07 January 2003 (orbit 40343 frame 2727). The rightmost dark areas along the coast are with high probability oil slicks. The town along the coast (cluster of bright dots on the left) is Gijon (Asturias region). See tracking map for this acquisition.	Envisat ASAR acquisition of 07 January (orbit 4471). Possible oil slicks. The image covers the coast of the Asturias region.
ERS SAR acquisition of 13 January 2003 (orbit 40429 frame 2745). The rightmost dark areas along the coast are with high probability oil slicks. The image covers the coast of the Galicia region. See tracking map for this acquisition.	Envisat ASAR acquisition of 13 January (orbit 4557). Possible oil slicks.
	ERS SAR acquisition of 13 January 2003 (orbit 40436 frame 873). Possible oil slicks. The image covers the Galicia and Asturias regions. See tracking map for this acquisition.
	ERS SAR acquisition of 16 January 2003 (orbit 40472 frame 2709 1st image above, 2727 2nd image above, 2745 left image). The rightmost dark areas along the coast are with high probability oil slicks. The image covers the north coast of the Galicia region. See tracking map for these acquisitions.
	Envisat ASAR acquisition of 16 January (orbit 4600). Possible oil slicks. The image covers the coast of the Galicia region. See tracking map for this acquisition.
	ERS SAR acquisition of 17 January (orbit 40486 frame 2727). The dark area is with high probability oil slicks. The image covers the coast of the Basque Country. The city of Bilbao is shown as a cluster of bright points in the image along the coast. See tracking map for this acquisition.
	ERS SAR mosaic acquisition of 20 January 2003 (orbit 40536 frame 873_855). The rightmost dark areas are with high probability oil slicks. See tracking map for this acquisition.
ERS SAR acquisition of 23 January (orbit 40579 frame 873). The dark area is with high probability oil slicks. The image covers the coast of the Cantabria region. The city of Santander is shown as a cluster of bright points in the image along the coast. See tracking map for this acquisition.	Envisat ASAR acquisition of 23 January (orbit 4707). Probability oil slicks. The image covers the coast of the Spanish and French (Aquitaine) coasts. See tracking map for this acquisition.
	Envisat ASAR acquisition of 25 January (orbit 4736). Possible oil slicks. The image covers the north coast of the Galicia regions. See tracking map for this acquisition.
ERS SAR acquisition of 26 January 2003 (orbit 40615 frame 2727). The rightmost dark areas are with high probability oil slicks. The image covers the north coast of the Asturian region. See tracking map for this acquisition.	Envisat ASAR acquisition of 26 January (orbit 4743). Possible oil slicks. The image covers the coast of the Galicia and Asturias regions. See tracking map for this acquisition.
	ERS SAR acquisition of 01 February (orbit 40701 frame 2745). The rightmost dark areas are with high probability oil slicks. See tracking map for this acquisition.
	Envisat ASAR acquisition of 07 February (orbit 4922). Possible oil slicks. The image covers the coast of the Galicia regions. See tracking map for this acquisition.
ERS SAR acquisition of 08 February (orbit 40801 frame 2727). The dark areas near the coast are with high probability oil slicks. The image covers coast of the Asturian region. See tracking map for this acquisition.	Envisat ASAR acquisition of 08 February (orbit 4929). Possible oil slicks. The image covers the coast of the Galicia and Asturias regions. See tracking map for this acquisition.
ERS SAR acquisition of 08 February (orbit 40808 frame 873). The dark area is with high probability oil slicks. The image covers the coast of the Cantabria region. See tracking map for this acquisition.	Envisat ASAR acquisition of 08 February (orbit 4936). Probability oil slicks. The image covers the coast of the Spanish and French (Aquitaine) coasts. See tracking map for this acquisition.
ERS SAR acquisition of 11 February (orbit 40851 frame 873). High probability oil slicks. The image covers the coast of the Cantabria region. See tracking map for this acquisition.	Envisat ASAR acquisition of 11 February (orbit 4972). Possible oil slicks. The image covers the coast of the Galicia regions. See tracking map for this acquisition.
	Envisat ASAR acquisition of 11 February (orbit 4979). Probable oil slicks. The image covers the coast of the Spanish and French (Aquitaine) coasts. See tracking map for this acquisition.
	Envisat ASAR acquisition of 13 February (orbit 5008). Possible oil slicks. The image covers the coast of the Galicia regions. See tracking map for this acquisition.
	ERS SAR acquisition of 21 February (orbit 40987 frame 2727). High probability of oil slicks. The image covers the coast of the Basque Country. See tracking map for this acquisition.
	Envisat ASAR acquisition of 01 March (orbit 5237). Possible oil slicks. The image covers the south coast of the Galicia region. See tracking map for this acquisition.
ERS SAR acquisition of 08 March (orbit 41202 frame 2727). Possible oil slicks. The image covers the coast of the Galicia regions. See tracking map for this acquisition.	ERS SAR acquisition of 08 March (orbit 41209 frame 873). Possible oil slicks. The image covers the coast of the Galicia regions. See tracking map for this acquisition.
	ERS SAR acquisition of 11 March (orbit 41252 frame 855). Possible oil slicks. The image covers the coast of the Galicia regions. See tracking map for this acquisition.
	ERS SAR acquisition of 12 March (orbit 41259 frame 2727). Possible oil slicks. The image covers the coast of the Asturias regions. See tracking map for this acquisition.
	ERS SAR acquisition of 15 March (orbit 41302 frame 2727). Possible oil slicks. The image covers the coast of the Asturias regions. See tracking map for this acquisition.