Bad News for Pollution Monitoring - US Needs a Radar Satellite, Stat!

It appears that we've lost one of the most important tools in the field of Earth observation:  on April 8, the Envisat satellite stopped communicating with its handlers at the European Space Agency.  While this is not happy news, the satellite was a real workhorse well beyond its expected lifespan and was an outstanding success for ESA's program.

We routinely used radar satellite images collected by Envisat's ASAR sensor, and low-resolution optical-infrared images from the MERIS instrument, to monitor places around the world for oil pollution related to offshore oil and gas development and shipping.  As a tool for tracking vessels throughout the ocean, ASAR was also useful for monitoring fishing. 

Here's a recent example of our work using ASAR, illustrating and measuring Shell's major oil spill off the coast of Nigeria last December: 

Envisat ASAR image capturing Shell oil spill off Nigeria in December 2011. Image courtesy European Space Agency.

There are other options, none quite as good as ASAR for its combination of coverage, capability and availability, and cost.  We've used radar satellite images from the TerraSAR-X and Cosmo-SkyMed systems, operated by Germany and Italy, for various oil spills including the BP / Deepwater Horizon disaster in 2010 and the Montara blowout and spill off Australia in 2009.  Canada's commercially operated Radarsat is an excellent system comparable to Envisat's ASAR, although the data cost makes large-area monitoring a very expensive endeavor.  And the European Space Agency is planning to launch Sentinel as a followup to the Envisat program, although that launch is not expected for at least a year. 

Which brings me to my #1 complaint about the US space program:  why doesn't the US have its own civilian radar imaging system?  We once led the world in this technology with the incredible success of SeaSAT way, way back in the day (remember 1978? we WERE the champions!) and we haven't launched a civilian radar satellite since.

This is a big mistake.  Radar imaging satellites are the #1 tool for conducting cost-effective, routine monitoring of large, remote ocean areas to detect and track vessels and pollution.  Other countries are using imagery hand-in-hand with their enforcement agencies to clamp down on pollution, illegal fishing activity and smuggling.  The U.S. has vast, far-flung ocean spaces to manage, amounting to half of our total territory.  Maritime monitoring has evolved into a national security issue far too important for the U.S. to continue being dependent on foreign- and commercial-operated radar satellites.  Congress, let's get on the ball and fix this glaring security gap.   

Radar Satellite Image Shows Oil Slicks Seen August 30

An Envisat ASAR satellite radar image of the Gulf taken at about 10:50 pm local time on August 30 shows distinctive slicks corresponding with video and photos taken during an overflight earlier that day by Bonny Schumaker / On Wings of Care.  This image is complicated - NOAA/NODC data buoys in the area recorded very low wind speed (2-3 meters/sec) when the satellite passed overhead, near the lower limit for oil slick detection.  The thin spaghetti-like strands of dark slick throughout this area are most likely tendrils of natural surfactants that commonly appear on low-wind radar images of the ocean surface.  But the size, shape and appearance of a 14-mile-long slick that seems to originate at the 23051 Site matches many observations we've made on satellite imagery since we discovered a chronic leak at that location. And the large dark patch at the location of the August 30 overflight apparently confirms Bonny's observations with an area of slick covering about 122 square kilometers. Given a minimum observable thickness on radar of 0.1 microns under these low-wind conditions, that would represent a minimum of 3200 gallons of oil.

First, here's what the August 30 radar looks like.  The Mississppi Delta is the bright birds-foot pattern on the left edge of the image.  Water is medium-gray; slicks are black:

Envisat ASAR image taken August 30, 2011 about 10:50 pm local time. Image courtesy European Space Agency.

Here's the same chunk of image with markers showing the chronically leaking 23051 site, the Deepwater Horizon wreckage site, and the location of Bonny's August 30 oil slick photos and video. Seafloor pipelines in yellow; recently troubled Destin pipeline shown in brown; active oil and gas platforms and other structures, including seafloor manifolds, are orange dots; natural seep locations are green dots:

Same area with features of interest marked. Image courtesy European Space Agency.

Zooming in, here's the August 30 radar image again showing a distinct patch of slick about 16 miles northeast of the BP / Deepwater Horizon oil spill site.  Orange dots are active oil and gas production facilities (platforms, manifolds):

Detail from Envisat ASAR image taken August 30, 2011 about 10:50 pm local time. Image courtesy European Space Agency.

Same area with other features marked for reference (pipelines in yellow, natural seeps are green dots). The brown highlighted pipeline is part of the Destin gas pipeline network, operated by BP, that was coincidentally (?) shut down on August 30:

Detail from Envisat ASAR image taken August 30, 2011 about 10:50 pm local time. Image courtesy European Space Agency.

Here's what the same patch of Gulf looked like on a radar image taken four days earlier, on August 26.  A small, 4-mile-long slick is visible just above the word "wreckage" - it's about equidistant from a subsea manifold in the area and a couple of natural seeps, so either of these could be the source.  But this slick doesn't seem related to the large patch observed on August 30:

Detail from Envisat ASAR image taken August 26, 2011. Image courtesy European Space Agency.

As usual, we'll keep looking at this area as we get new imagery and information, and will let you know what we learn.

Bilge Dumping off Vietnam - February 22, 2012

We've posted about bilge dumping before - the practice of flushing the oily slop out of your vessel, straight into the ocean.  It's illegal in a lot of places, but it is very hard to enforce.  SkyTruth's daily offshore monitoring program just caught this fine (awful?) example of bilge dumping off the coast of Vietnam, in a major north-south shipping lane about 115 miles offshore: 

Envisat ASAR satellite radar image off Vietnam, February 22, 2012. Image courtesy European Space Agency.

Zooming in on those black streaks, and turning the image west-up, here's a closer look at this mess:

Envisat ASAR image courtesy European Space Agency.

More images and analysis after the jump....

Campos Basin Oil Spill, Brazil - Slicks Dissipating?

Envisat ASAR image of Campos Basin taken November 22, 2011. Surface winds too strong to reliably detect thin oil slicks. Bright spots are vessels and oil platforms. Image courtesy European Space Agency.

Today's Envisat ASAR satellite radar image of the Campos Basin, covering the location of the Chevron / Transocean oil spill, shows no sign of an oil slick. It was taken at about 9:30 am local time.

However, the wind speed was fairly strong in the area at the time. According to the satellite scatterometer data collected by the ASCAT system, surface winds were blowing at 15-25 knots (8-13 meters per second). This is strong enough to overwhelm very thin oil slicks (the optimum wind speed for detecting slicks on radar images is about 3 - 10 meters per second):

Surface wind speed and direction derived from ASCAT scatterometer data at nearly the same time as the November 22 radar satellite overpass.

So it is possible that very thin oil slicks remain in the area, but it is encouraging that we don't see signs of thick oil... (more text and images after the break)

Radar Satellite Images of BP / Deepwater Horizon Spill Area, September 11 and 14

We are focusing particularly hard on the area of the BP / Deepwater Horizon oil spill in recent days, after documentation of slicks in the area near the Macondo well site on August 19, and about 15 miles to the northeast on August 30.  The small area of thin slick sampled by Ben Raines on August 23, about one mile from the well site, was chemically tested by Ed Overton of Lousiana State University who declared it a "dead ringer" for Macondo crude oil; possibly leaking from the wrecked Deepwater Horizon rig or the 5,000' of collapsed riser pipe on the seafloor around the Macondo well. As far as we know, no samples were collected from the much more extensive patch of slicks observed on August 30.  Tropical Storm Lee blew in and knocked everyone out of the Gulf soon thereafter.

Some have suggested that crude oil from the reservoir 8,000' below the seafloor might be working its way up through faults and fractures in the bedrock, or along the Macondo wellbore.  If that happens we would expect to see "seepage on steroids" as oil works its way to the seafloor along multiple pathways and floats up to the ocean surface to form persistent oil slicks.

We would be able to observe those slicks on satellite imagery, just like we repeatedly observe slicks from active natural oil seeps throughout much of the Gulf.  Radar imagery is the go-to tool for the job.  A radar image taken on August 30 showed a patch of slick matching the area and description given by Bonny Schumaker when she flew over that site earlier in the day; an image taken a few days earlier, on August 26, showed nothing interesting in the vicinity. 

We've got a couple more recent images to look at.  This one shot on September 11 shows a lot of slicks in the area - a very complicated pattern typical of low-wind conditions (about 2 m/s), where dark, swirly patterns of natural surfactants usually present on the ocean surface are mingled with slicks from natural oil seeps and those possibly caused by oil leaks and spills, making it difficult to draw any firm conclusions (although note the slick apparently emanating from the location marked 23051, where we've documented a chronic leak from hurricane-damaged wells and routinely observe similar slicks) :

Envisat ASAR image taken September 11, 2011. Eastern edge of the image appears at right (black fill denotes no image data). Mississippi Delta is bright "bird's foot" at left center.  Image courtesy European Space Agency.

Here's the exact same area as it looked on another Envisat ASAR radar image shot at about 1pm local time yesterday under good conditions (wind blowing from the northwest at 4 m/s). We see a slick once again associated with the 23051 site, a few small slicks west and southwest of the Macondo well location that are very closely associated with known natural seep locations, and a variety of larger slicks in Breton Sound where we routinely see reports of leaks and spills from offshore oil facilities (and so can you, if you subscribe to SkyTruth Alerts):

Envisat ASAR image taken September 14, 2011. Mississippi Delta is bright "bird's foot" at left center.  Image courtesy European Space Agency.

And here's the same shot, with pipelines shown in orange, active platforms as orange dots, and natural oil seeps shown as green dots (seep data provided by Florida State University):

Envisat ASAR image taken September 14, 2011, with oil and gas infrastructure (orange) and known natural seep locations (green).  Image courtesy European Space Agency.

The upshot: we're not yet seeing a trend that would support the idea that oil is working its way up from the Macondo reservoir and turbocharging the existing natural seeps in the area, or forming new sites of chronic leakage.  But we don't have enough imagery yet to say for certain it isn't happening.  All we can do is keep looking, and compare what we're seeing now with images of this area from before the BP / Deepwater Horizon spill began last April.  We're working now on getting those historical images so we can establish that pre-spill baseline.

Drilling off Cuba, Drilling in the Arctic - And No Monitoring Capability. Really?!

Soapbox time!

Here at SkyTruth we've been concerned about the loss of the world's premier tool for offshore monitoring with the demise of the European Space Agency's excellent Envisat satellite in early April.  The successor, Sentinel, won't be launched until sometime next year at the earliest.  Meanwhile, we do have alternatives:  RADARSAT, Cosmo-SkyMed, and TerraSAR-X.  But these are all commercially operated systems and the images range in price from about $1200 to as much as $7500, making them prohibitively expensive for routine monitoring of large areas in the open ocean.  

Envisat ASAR radar image showing precise location of Scarabeo-9 drill rig in Cuban waters of Florida Straits.  Image courtesy European Space Agency.

This is all an unfortunate and inevitable consequence of the fact that, for reasons we can't fathom, the US has decided not to operate any civilian radar imaging satellites.  We led the world in this technology with the launch of SeaSat back in 1978, but now we're dependent on foreign-operated systems.  We consider this a national security fail of a high order: radar imaging satellites are a key tool for establishing and maintaining maritime domain awareness, and effectively managing and protecting our nation's vast ocean territory. Maybe the National Reconnaissance Office has a couple of extra radar spy satellites lying around that they could donate to NASA for civilian use.  The intelligence agencies seem to have plenty of $$ to build more toys than they can use while NASA's satellite program is starving for cash. But I digress...

The BP / Deepwater Horizon oil spill in the Gulf of Mexico highlighted the value of satellite imagery for independently assessing the size and severity of the spill, tracking the day-to-day movement of the oil slicks, and identifying the ocean and coastal areas directly impacted by the oil.  Our work since then has demonstrated the value of radar imagery in particular for detecting bilge-dumping from oceangoing vessels, a major source of marine pollution worldwide; for detecting vessels that may be operating illegally in areas that are off-limits to fishing; and for comparing the pollution as reported by polluters, with what we can actually observe.  

Now companies from around the world are rushing to do deepwater drilling in Cuban waters close to Florida, with no agreement in place that will allow US companies to assist in the event of a major oil spill. Pemex, the state oil company of Mexico, has announced plans to begin high-risk ultra-deepwater drilling in the Gulf despite their alarming lack of deepwater expertise.  Drilling is set to begin as soon as July in the Arctic Ocean off Alaska, raising a host of questions about the impact of day-to-day pollution in that sensitive environment and our ability to effectively clean up an oil spill in typical Arctic ice and weather conditions, far from bases of operation.  And, as SkyTruth and our Gulf Monitoring Consortium partners have demonstrated, we continue to have spills every day in the Gulf of Mexico that are unreported, underreported, and rarely investigated: a continuing moral hazard of tolerating sloppy operations that, in our opinion, sets the stage for the next chain of error that leads to a catastrophic spill. 

Shell's Kulluk drill rig under tow, set to drill in the Arctic Ocean off Alaska this summer.  Source:  Fuelfix.com.

Now, more than ever, we need a public source of routine radar images for all of these areas to allow everyone to see what's happening, to provide assurance that there are no undue environmental problems associated with these innately risky developments, and to stand ready to immediately swing into action to support response efforts should a serious accident occur. 

We call on the US government to work with the commercial radar image companies to provide a publicly accessible stream of radar imagery until Sentinel, or some other radar imaging system, fills the big monitoring gap left by the demise of Envisat.  We would gladly participate in discussions to help make this happen, and soon.  

July is not very far off. And to let drilling proceed in the Arctic Ocean without a transparent, public monitoring system and spill-response tool in place strikes us as both reckless and irresponsible:  a needless escalation of the risks involved with drilling, and a willful disregard of the concerns that have been voiced by tens of thousands of Americans.  Let's fix this problem now.

Cuba Offshore Drilling Rig Spotted on Radar - Small Slick Reported

We've found it.

The big semisubmersible drill rig, built in China and now drilling a deepwater oil well for the Spanish company Repsol in the Florida Straits off Cuba (hey, it is a global industry), has finally made an appearance on a radar satellite image.

This Envisat ASAR image, shot at 11:43 pm local time on March 30, shows a trio of very bright spots about 17 miles north-northwest of Havana.  We think the largest of these spots, with an interesting cross-shaped "ringing" pattern often seen on radar images of big, boxy metal objects, is the Scarabeo-9 rig.  The other two spots may be crew vessels or workboats:

Detail from Envisat AASAR satellite radar image of Florida Straits, taken on March 30. 2012. We infer the large bright spot is the Scarabeo-9 semisubmersible drill rig.  Image courtesy European Space Agency.

The location marked in orange is a report we just got through the SkyTruth Alerts that a small possible oil slick was sighted nearby during a US Coast Guard overflight yesterday morning. We don't think this is anything alarming; it's probably just some of the typical oily crud you'll get from an active drilling operation at sea, that we observe on a regular basis in the Gulf of Mexico with our Gulf Monitoring Consortium partners. 

For those who want to know, here is our analysis of the location of the Scarabeo-9 drill rig based on this radar image.  If anyone can confirm this is indeed the location of the rig, please let us know:

 23.374496° North latitude / 82.492283° West longitude

Here's a zoomed-out look, showing the coastline of Cuba and the city of Havana:

Envisat ASAR radar satellite image courtesy European Space Agency.

   And here's the big picture, showing Cuba, Key West and the rig location:

We'll keep watching this area.  Many people are concerned about the potential of a major spill from this site affecting the east coast of Florida and the southeastern US, and the lack of oil spill response coordination and cooperation between Cuba and the United Sates.

Slicks in Campos Basin, Offshore Brazil - March 20, 2012

Brazil is coming down hard on Chevron for the relatively modest oil spill that occurred last November when they lost control of a deepwater exploration well in the Frade field of the Campos Basin, about 75 miles offshore.  A federal prosecutor just filed a lawsuit and criminal charges against Chevron and their drilling contractor Transocean.  Seventeen executives of those companies have also been charged.

Brazil's President has made it clear that the country will treat all oil companies, domestic and international, the same when it comes to safety.  Petrobras, the Brazilian national oil company, is the main operator in Brazilian waters, and they've had their own share of problems lately.  We've observed small slicks from Petrobras facilities since we started our daily monitoring of this area a few months ago.  And this Envisat ASAR radar satellite image of the Campos Basin, taken at 9:18 pm local time on March 20, shows what appear to be long, narrow slicks emanating from several Petrobras production platforms and FPSOs:

Detail from Envisat ASAR radar satellite image of Campos Basin off Brazil, taken March 20, 2012.  Oil production platforms and FPOs indicated by colored dots. Possible oil slicks (dark streamers) appear to emanate from several facilities, shown in orange.  Image courtesy European Space Agency.

This is a complex image.  Platforms, FPSOs, drill rigs and vessels appear as bright spots on radar. The large, indistinct dark areas in the upper part of the image are also slicks, but not caused by oil (a "slick" is any patch of smooth water, appearing dark on a radar image). Instead, these patches are probably caused by areas of very low wind speed, and/or by heavy rainfall.  Sea-surface wind data, taken almost the same time as the radar image above, indicate there was unsettled stormy weather in the area:

Surface wind speed and direction derived from satellite radar scatterometer data, offshore Brazil, at about 8 pm local time on March 20. Black flags indicate possible rainfall.

More images and maps after the jump....

Oil Pollution off Nigeria - Other Sources?

After flying journalists over the remnants of the Bonga FPSO oil spill off Nigeria,Shell pointed out that they are not the only polluters in this part of the world, and will clean up another small spill in the area not related to any of their operations.

That certainly doesn't excuse their (much larger) mess but they are correct:  satellite images of the west coast of Africa, like some other coastal regions around the world, routinely show signs of oil pollution from other sources, especially bilge-dumping by vessels large and small. We don't know if it's legal in this area; it is not legal in US or Canadian waters. Radar satellite imagery is an excellent tool for detecting bilge-dumping. 

This Envisat ASAR image taken on December 18, 2011 shows a 100-mile-long slick caused by bilge dumping from a large vessel that was traveling toward the southeast on a course taking it very close to the Bonga FPSO (we've inferred the location of the FPSO from multiple radar satellite images; if anyone has the exact lat/lon coordinates please pass them along to us): 

Envisat ASAR image taken December 18, 2011 showing oily bilge dump from a passing vessel northwest of the Bonga oil field off Nigeria. Image courtesy European Space Agency.

At 1 micron thick this bilge slick holds about 80,000 gallons of oily material.  Projecting the vessel track back to the northwest, we land near the city of Aneho on the Togo coast. There is an industrial facility in the area that appears to have an offshore loading system.  It could be the point of origin for the suspect vessel, but we really have no way of knowing:

Projecting backward along bilge slick to shore. Envisat ASAR image courtesy European Space Agency.

Here's what it looks like in Google Maps.  Does anyone have any information about this facility?

View Larger Map

Gas Well Blowout in the North Sea

On March 26, Total reported a gas leak that forced them to evacuate more than 200 workers from a production platform in the Elgin field of the central North Sea, about 150 miles east of Aberdeen, Scotland.  It soon became clear they had an uncontrolled blowout of natural gas and liquid gas condensate, a potentially explosive situation that has caused other companies to evacuate and shut down operations at neighboring facilities miles away from Totals' Elgin platform.  The Oil Drum has compiled excellent information about this serious ongoing incident.  Hopefully the failed well will collapse on itself ("bridge over") and shut off the high-temperature, high-pressure flow of gas from this deep reservoir.  Otherwise, it may continue to flow and pose an extreme fire and explosion hazard until a relief well can be drilled, which could take a couple of months.

Map showing location of Elgin platform in North Sea, site of ongoing gas well blowout.

 This leak is mostly natural gas escaping into the atmosphere at sea level -- something we can't see on satellite imagery -- but a small slick of liquid gas condensate has also been reported at the site.  This Envisat ASAR radar satellite image, taken yesterday at about 9:23 pm local time, shows a patchy slick covering about 89 square kilometers (34 square miles).  The platform itself appears as a very bright spot on the radar image but it's covered up by our yellow rig icon marking the location:

Detail from satellite radar image taken March 27, 2012, showing small slick (probably natural gas condensate) apparently originating from gas well blowout at Total's Elgin platform.  Envisat ASAR image courtesy European Space Agency.

Chevron Reports Minor Slick From Leak in Campos Basin, Offshore Brazil

Chevron and Brazilian regulators reported that a small, fresh oil slick has appeared near the site of Chevron's blowout last November in the deepwater Frade oil field in Brazil's prolific Campos Basin. This is not entirely unexpected given the nature of the problem that Chevron had with the well being drilled by the SEDCO 706 rig: an unknown amount of oil escaped laterally from the well into surrounding bedrock, and worked its way up to the seafloor along a pre-existing natural fault.  It will take some time for all of that oil to emerge, so we've been anticipating chronic small oil slicks at this location.

But optical satellite imagery of this area (MODIS and MERIS) have had problems with clouds and haze for the past few days, so we haven't seen any sign of the latest slick. Radar images don't have that problem, but the most recent radar image we have was taken at about 9pm local time on March 9, and it looks clean around the SEDCO 706 site:

Detail from radar satellite image taken March 9, 2012, showing area of reported Chevron leak. No slick is apparent. White dots are large metal objects on the water:  drill rigs, FPSOs, oil platforms or vessels.  Orange dots are the locations of FPSOs and platforms from Brazilian government data.  Red marker indicates the location of the SEDCO 706 rig when it was drilling the well that caused the initial leak in November 2011.  Envisat ASAR image courtesy European Space Agency.

We do see a small slick on this image, though, about 80 km south-southwest of the Chevron leak site.  It is quite small, covering about 2 square kilometers, and appears to be associated with Petrobras P38, an FPSO in the Marlim Sul field that recently began handling new production from platform P56:

Small slick apparently associated with Petrobras FPSO P38 in the Marlim Sul Field off Brazil.  Detail from radar satellite image taken March 9, 2012.  Orange dots mark the locations of FPSOs and platforms from Brazilian government data. Envisat ASAR image courtesy European Space Agency.

This appears to be a very small spill -- at 1 micron thick it would only amount to 528 gallons -- but recent spills off Nigeria and affecting the beach at Tramandai in Brazil, should put FPSOs on everyone's radar here in the US.

Small Slick at Chevron's Blowout off Nigeria

Chevron's gas-well blowout in the Funiwa field off Nigeria continues to burn as efforts are underway to drill a relief well.

Fire from blowout at Chevron gas well off Nigeria. Image source: pilotafrica.com

This Envisat ASAR satellite radar image taken today (February 27) shows a small slick apparently emanating from the site where the doomed KS Endeavor rig was drilling. We've seen a small slick repeatedly at this area since the blowout occurred.  Possibly there are some petroleum liquids coming up with the gas, and not completely burning off.  The slick on today's image is about 10 miles long:

Small slick apparently emanating from location of Chevron's Funiwa-1A gas well blowout.  Envisat ASAR image taken February 27, 2012.  Image courtesy European Space Agency.

Small Slick at Platform P-51, Marlim Sul Field, Brazil

Platform P-51 in Marlim Sul field of Brazil's Campos Basin.  Source: Wikipedia.

 An Envisat ASAR radar satellite image taken on February 23, 2012 shows a small slick apparently emanating from Platform P-51 in the Marlim Sul field of the Campos Basin, about 70 miles offshore:

Envisat ASAR image taken February 23, 2012 showing small slick apparently emanating from location of Platform P-51.  Image courtesy European Space Agency.

Covering 10 square kilometers, this slick represents a spill of about 2600 gallons, assuming an average oil slick thickness of 1 micron.

Small Slick Visible At Site of Chevron's Blowout and Fire off Nigeria

Teri noticed a small slick on today's Envisat ASAR radar satellite image covering the site of Chevron's blowout and fire off the coast of Nigeria. We measure it at about 18.6 kilometers long, extending about 39 square kilometers.  It appears to be very thin.  Assuming the slick is, on average, one micron thick, that amounts to about 9,500 gallons of some oily substance -- possibly unburned natural gas condensate, since this was reported by Chevron to be a gas exploration well that was not creating any oil slick:

Detail from Envisat ASAR image taken February 8, 2012. Location of blowout marked by rig symbol.  Image courtesy European Space Agency.

This MODIS image taken on February 3 (and this one from February 5) shows the ongoing fire where the KS Endeavor drill rig used to be, before it toppled over and sank: 

Matching detail from a NASA/MODIS image taken February 3, 2012 showing continuing fire (red spot) at site of Chevron blowout.  Image courtesy MODIS Rapid Response Team.

Chevron Blowout and Rig Fire off Nigeria - Small Slick Visible on Radar Today

The K.S. Endeavor jackup drill rig operated for Chevron in shallow water about 5 miles off the coast of the Niger Delta is continuing to burn.  This blowout probably won't be under control until a relief well can be drilled. Chevron confirms the rig had been drilling a gas exploration well they call the Funiwa Deep-A, with a planned depth of 16,500 feet.  But the well had only reached a depth of 12,945' when the blowout occurred early Monday morning.  That's comparable to the depth of BP's Macondo well that blew out in the Gulf of Mexico in 2010, launching what would become the world's worst accidental oil spill.

The Funiwa field has both oil and gas reservoirs.  A big question on everyone's mind:  Could this lead to a major oil spill?  Is there a lot of oil already coming out of the well right now, fueling this blowtorch of a fire?  Some have reported sighting slicks and sheen in the vicinity.

Satellite imagery gives us some reason for optimism so far.  This Envisat ASAR radar satellite image taken today shows only a very small slick around what we infer to be the location of the burning Endeavor, based on multiple observations of the fire itself on MODIS 7-2-1 satellite images and the bright spots on the radar image that indicate big hunks of metal out in the water (rigs, vessels, platforms):

Detail from Envisat ASAR image taken January 20, 2012 showing small slicks in vicinity of burning K.S. Endeavor drill rig.  Inferred location of rig shown. Large dark patches along the coast are probably caused by turbid river water entering the ocean.  Image courtesy European Space Agency.

[More images and analysis after the jump...]

Chevron Oil Spill, Brazil - Small Slick December 6, 2011

Envisat ASAR radar image taken December 6, 2011. Image courtesy European Space Agency - click for larger version.

We've been getting a few Envisat ASAR radar satellite images of the Campos Basin off the coast of Brazil, covering the Frade field, where Chevron and their contractor Transocean experienced a loss of well control during drilling on November 7 that initiated an oil spill. Apparently "unexpected" reservoir pressure caused drilling mud to back up in the well, allowing highly pressurized oil (and probably some gas) to leak out into the surrounding bedrock.  This oil has since been working its way up to the seafloor through faults or fractures in the rock, emerging along a line of unnatural seeps on the seafloor, and floating up to the surface to create visible oil slicks.  The well was plugged a week after the spill began, and since then visible slicks have diminished in size. 

Chevron may also be required by Brazilian authorities to drill a relief well to inject cement into the well at depth -- an expensive proposition -- to formally abandon the failed well.  And a Brazilian federal prosecutor based in Campos has filed a $10.8 billion suit against Chevron and Transocean, and is seeking to have both companies permanently banned from drilling in Brazil. 

Meanwhile in Bohai Bay, China, ConocoPhillips has found little environmental damage from their spill earlier this year in the Peng Lai 19-3 field.  But they did reveal that their spill, like Chevron's, was caused "due to unexpected pressure encountered while drilling."  A mistake like that can lead to a blowout and major spill.  I hope all of the technical details from both of these incidents are being disclosed and will be made available to the public and to US regulators.

The radar satellite image above, taken on December 6, 2011, shows a very small slick originating near the location of Transocean's SEDCO 706 drilling rig that was installing Chevron's failed well. The slick is about 7.3 miles long and a few hundred yards wide, comparable to the slicks created by natural oil seeps in the Gulf of Mexico.  Wind conditions were good for slick detection at the time, blowing at about 10 knots (5 meters per second).  Several other small slicks are visible near a cluster of oil platforms (bright spots) about 50 miles south of the SEDCO 706.  This is within the southern Campos Basin, and these slicks may be the result of minor spills or leaks from platforms, pipelines, or vessels operating in one of the many offshore fields in the region.

Campos Basin Oil Spill, Brazil - Small Slick November 25

We've just processed an Envisat ASAR radar image of the Campos Basin that was taken on November 25.  As expected, it shows a much smaller apparent oil slick originating from the location of the SEDCO 706 drilling rig, operated for Chevron by Transocean, than we observed back on November 12:

Envisat ASAR satellite radar image taken November 25, 2011. Slicks are dark streaks and patches. Location of SEDCO 706 drill rig is marked. Image courtesy European Space Agency.

Surface wind speed over the leak site was good, about 5-15 knots (3-8 meters/sec), blowing from the north-northeast.  A very narrow slick about 120 meters wide and 50 kilometers long extends south from the rig location, covering about 6 square kilometers.  Assuming the slick is 1 micron thick, we estimate it holds about 1,584 gallons (38 barrels) of oil.

There are other small slicks in the area to the west and southwest of the Chevron leak site.  Some of these may be from natural oil seeps in the basin, other sources of natural surfactant such as phytoplankton, or leaks and spills from vessels and other offshore facilities.

Gulf Overflight and Radar Image (August 30) Now in Google Earth

Our friends at SarSea created an interactive Google Earth file (get it here) that shows the flight path of Bonny Schumaker's August 30 overflight and the photos and video she took of the oil slicks she observed during that flight. Here's an overview that also shows the location of the Macondo well - the source of last year's BP / Deepwater Horizon oil spill - and the 23051 Site where we've been watching a chronic leak from a cluster of wells that were damaged by Hurricane Ivan waaaay back in 2004, overlain on an Envisat ASAR radar satellite image that was taken at about 11pm that night:

Bonny Schumaker's August 30 flight path and photo points, overlain on August 30 radar satellite image. Envisat ASAR image courtesy European Space Agency.

ConocoPhillips Oil Spill in Bohai Bay - They Have Company

The Chinese government and fishermen are really hammering ConocoPhillips over their recent and apparently still unresolved pair of oil spills from two platforms at the Penglai 19-3 offshore field in Bohai Bay.  We observed small oil slicks there on a radar image taken on June 11. Reports of continued leakage from one of the platforms, where they were injecting drilling fluids beneath the seafloor for disposal, suggest they may have cranked up the pressure too high and ruptured the well casing.  Good thing that's not a high-pressure production well or we could be looking at a major multi-month spill.

Here's a new version of the June 11 image, with a scale bar and some helpful annotation pointing out what we infer to be the Penglai 19-3 oil field based on maps and descriptions of the location that we've read (does anyone have actual lat/lon coordinates? call us!).  We've also marked slicks and a couple of vessels with distinctive wakes (there are more - pick 'em out!): 

Detail from Envisat ASAR satellite radar image of Bohai Bay, China, showing oil slicks and offshore oil platforms at what we infer to be the location of the Penglai 19-3 offshore oil field.  Image taken on June 11, 2011, courtesy of the European Space Agency.

We're not making any excuses for the problems caused by ConocoPhillips, but we've been looking at radar satellite images of the Bay and it seems pretty clear that there is routine oil pollution throughout the Bay that is not attributable to the Penglai field operation.  Penglai 19-3 lies just south of a major east-west shipping lane where we see slicks, probably from vessels, on a couple of images.  Here's an example, showing an obvious slick from a vessel that stretches for nearly 40 miles:

Detail from Envisat ASAR image taken on August 21, 2011, showing an area in Bohai Bay about 60 miles north-northeast of the June 11 detail above. Slick from vessel is about 40 miles long.

So ConocoPhillips may be fouling the Bay, but it appears they're not the only ones.

Shell Spill in North Sea - Radar Draws a Blank

Just got a radar satellite image from the European Space Agency (ESA) - it's from their Envisat satellite, ASAR sensor. It was taken on August 13 over the North Sea, where Shell has been dealing with an oil spill from a pipeline near their Gannet Alpha platform.  At last report, Shell claims that they've spilled 67,000 gallons and that the failed pipe holds an additional 185,000 gallons, making this the worst spill in UK waters in ten years.

The leak apparently began on August 10, and was first reported on August 12.  We were hopeful this August 13 image would show the slick so we could estimate the size of this spill. But it's a blank - monotonous gray, with some broad faint streaks running diagonally from north-northwest to south-southeast that suggest the North Sea was being blasted with very strong winds when this image was taken, rendering the image unusable for detecting oil slicks.  Bright spots around the Gannet Alpha marker show platforms and possibly large vessels; as big angular hunks of metal, both are excellent radar reflectors:

Overview showing radar satellite image and location of Gannet Alpha platform. Envisat ASAR image courtesy European Space Agency.

Detail showing radar image in vicinity of Gannet Alpha platform. Uniform, medium-gray tone of image indicates strong surface winds.  Bright spots are platforms or vessels.

We'll keep looking for new images that might show what's going on here.