Gulf Oil Slick Growing – 2,233 Square Miles

MODIS satellite image taken this afternoon, April 27, shows growing oil slick in the Gulf.

We just processed a NASA/MODIS image taken from the Terra satellite this afternoon that shows slicks spread across 2,233 square miles, and within 22 miles of shore. See it here. The image suffers from clouds and haze (a problem we don’t have to deal with on radar images) so we used somewhat more sophisticated spectral processing to identify the oil slicks. And no, it’s not Photoshopped; we applied a modified Gaussian contrast-enhancement algorithm:

Spectrally enhanced version allows easier identification of oil slick on this cloudy / hazy image.

Gulf Oil Slick Dwarfs Response Vessels

Detail from SkyTruth image showing response vessels and Gulf oil slick on April 25.

We just got a detailed ALI satellite image from NASA that was shot two days ago, on April 25, when the oil slick was about 817 square miles in size (it has since more than doubled to at least 1,800 square miles). You can see several response vessels working at the periphery of the slick. The magnitude of the job they have to do is plain to see.

See more in our growing image gallery for this incident.

Gulf Oil Spill Covers 817 Square Miles

NASA/MODIS satellite image taken April 25 showing oil slicks from Deepwater Horizon disaster.

SkyTruth just processed a NASA/MODIS satellite image of the Gulf of Mexico that was taken early yesterday afternoon (April 25). Slicks and sheen (very thin slick) covers about 817 square miles, and reaches 50 miles away from the assumed point of origin (the site of the leaking well on the seafloor). We’ve posted this in our image gallery for this incident. We’ve also shown the last two positions of the rig that we were able to detect before it sank, as seen on NASA images from April 21 (also in our gallery).

UPDATE 4/27/10 1pm – We’ve added a very detailed image to our gallery, also taken on April 25, from NASA’s Advanced Land Imager (ALI) sensor carried on the Earth Observing-1 (EO-1) satellite. You can see response vessels, and gradations in the thickness of the slick and peripheral sheen. Meanwhile, the spill continues unabated, and the size of the oil slick has more than doubled since these NASA images were taken just two days ago. We hope to get new images soon.

Gulf of Mexico Oil Spill Getting Worse

Yesterday the Coast Guard reported that the damaged well on the seafloor in the Gulf of Mexico is leaking oil again, at a rate estimated to be 42,000 gallons (1,000 barrels) per day. This is bad news – it means the blowout preventer on that well is not doing its job, and that several attempts by BP, Transocean and the Coast Guard to operate a shutoff valve on the well using a robotic ROV have failed. The oil slick has grown rapidly and now covers 400 square miles.

Oil slick in the Gulf now covers 400 square miles. AP photo by Gerald Herbert, courtesy San Francisco Chronicle.

If the blowout and spill off Australia last year offer any lessons, it could be months before this well can be brought under control and the spill really and truly stopped. This is already a “major” oil spill by Coast Guard definition (>100,000 gallons), and a human tragedy. Economic losses include the $600-700 million dollar Deepwater Horizon drill rig, and as-yet untold millions in response and cleanup costs (and lawsuits from the people who have been hurt). But this blowout and spill in the Gulf now threaten to become truly catastrophic.

The NASA satellite imagery we used to track that Australia spill have been unavailable since Friday. As soon as we can get anything we’ll do our best to get it posted here.

Explosion and Fire at Deepwater Drilling Rig in the Gulf of Mexico

Smoke plume from burning drill rig; note oil slick at lower right. Image courtesy MSNBC; see their slideshow.


Firefighters working to control blaze at the Deepwater Horizon drilling rig in the Gulf of Mexico. Photograph courtesy of Rigzone. See more hi-res Coast Guard photos in SkyTruth gallery.

We’ve just begun seeing news reports of an explosion and fire last night that has forced the evacuation of 126 workers from an oil rig that was drilling an exploration well 41 miles off the Louisiana coast in the Gulf of Mexico. The Deepwater Horizon is a massive semisubmersible drill rig built in 2001. It’s owned and operated by Transocean Ltd, the world’s largest offshore drilling contractor, with a global fleet of more than 140 rigs. Transocean operates 14 rigs in the Gulf of Mexico.

11 workers are missing and 7 have been injured. The rig is still on fire (video of fire and evacuation of crew), and is listing.

The Deepwater Horizon semisubmersible offshore drilling rig.

The rig was built for drilling ultradeep wells in water far offshore, where most of the action is in the Gulf of Mexico. It’s under contract to BP and was drilling an exploration well in the Macondo prospect, in the Mississippi Canyon area of the north-central Gulf. The water depth there is almost 5,000 feet.

SkyTruth’s testimony to Congress last fall on the risks of offshore drilling was brushed off by some politicians. Maybe it’s worth looking at again.

UPDATE 4/21/2010 – Despite some reports to the contrary, Coast Guard says 12 workers are still missing. 15 were injured, 7 of them critically.

UPDATE 4/21/2010 – NOAA reports that nearly 1.2 million gallons of fuel oil are on the rig (#2 fuel oil or diesel), and that the Coast Guard has requested NOAA’s help in modeling oil spill trajectories in the event of a spill. I’m guessing that much of this oil is burning. See the official NOAA Incident Report. Thanks to blogger Seth Platt for the heads up.

UPDATE 4/21/2010, 7:10 pm – NBC Nightly News just reported that the rig is leaking oil into the water; and that the Coast Guard is trying to get an ROV or submersible that can shut off an underwater valve to cut the flow of fuel to the fire. This sounds like a “loss of well control,” or blowout, like the one that lead to disaster off Australia last year. Let’s hope they can get that valve closed. No word yet on the missing workers.

UPDATE 4/22/2010, 9:30 am – Coast Guard still searching for 11 missing rig workers; rig is still on fire. SkyTruth has started an image gallery for this incident that includes hi-res Coast Guard photos of the burning rig.

UPDATE 4/22/2010, 2:00 pm – CNN is reporting that the rig has sunk. The fire is continuing. Coast Guard is estimating that oil is spilling at a rate of 336,000 gallons (8,000 barrels) per day.

UPDATE 4/22/2010, 5:30 pm – SkyTruth analysis of two NASA satellite images taken hours apart yesterday suggests the Deepwater Horizon rig may have been drifting. Images show the rig moved almost 2-1/2 miles to the east in about 2 hours. We have no confirmation that the rig was drifting, and this would suggest a pretty fast clip. But the shorelines in the two images match up almost perfectly, so we have no exlanation yet for this apparent movement.

UPDATE 4/23/2010, 10 am – 11 rig workers still missing and Coast Guard reports that oil is no longer leaking from the damaged well on the seafloor. Not yet clear if this is because their attempt to shut off the well using an ROV has succeeded. Oil spill cleanup operations are proceeding with deployment of containment booms and skimmer vessels.