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.

Platform 23051 Site – Still Leaking, Magically!

Back on September 2 somebody submitted a pollution report to the National Response Center indicating an oil spill in the Gulf of Mexico, and it popped up in the SkyTruth Alerts system.  That’s depressingly common – there are typically a dozen or so reports of spills every day in the Gulf.  And this one came from a familiar place, the site of a former oil platform (#23051) about 12 miles off the tip of the Mississippi Delta, in Mississippi Canyon Block 20.  We’ve been systematically documenting a chronic leak there since we first became aware of it last summer during the unrelated BP / Deepwater Horizon spill.

But the September 2 report is magical:  The caller – presumably an employee of or contractor for the company – claimed a spill totalling 0.0000027 gallons.  That’s 1/500th of a teaspoon.

  • Magic Act #1: How did they measure it?
  • Magic Act #2: This vanishingly minuscule spill somehow created an observable oil slick 1,000′ long and 200′ wide, covering a total area of 4.6 acres with a “silvery sheen.”

Silvery sheen is at least 0.04 to 0.3 microns thick.  By our calculation, that’s a slick containing 0.2 to 15 gallons.  Sure, 2/10ths of a gallon isn’t much, but it is 74,000 times larger than the caller reported. Maybe this was a simple transcription error at the NRC.  But if not, this one gets the prize for ridiculousness, reinforcing our evolving theory that polluters are consistently underreporting the amounts of pollution. Cumulatively, given thousands of reported spills a year, these unreported amounts add up to a much bigger mess than the public has been lead to believe.  In a place like the western and central Gulf, maybe this is no big deal; but in new places where we’re moving ahead with drilling – the Virginia coast, the Arctic Ocean – the routine leaks and spills associated with coastal industrialization and offshore drilling might not be so easily shrugged off by tourists, fishermen, and the environment.

And by the way, we’re seeing a lot more than 5 gallons in the ongoing spill – 24/7/365 since September 2004 – from this hurricane-damaged cluster of wells.  The MODIS /Aqua satellite image below, taken on September 10, shows a slick originating at the 23051 site that extends almost 35 miles. And the radar satellite image at bottom, taken on August 30, shows a slick at the site that stretches about 13 miles. We’ve collected dozens of images showing slicks at this site routinely stretching more than 10miles.

Detail from MODIS satellite image taken September 10, 2011 showing 35-mile-long slick emanating from 23051 site at left.
Radar satellite image taken August 30, 2011, showing 13-mile-long slick at 23051 site at upper left.

We suspect that some of the oil slicks and occurrences of tarballs and other oil on the Louisiana coast are probably coming from this location, not from the BP / Deepwater Horizon site 40 miles offshore.  To help eliminate this possible source of confusion, scientists from National Wildlife Federation are taking a boat out today — guided by SkyTruth’s maps, coordinates, and image analysis — to collect a sample of the oil slick at the 23051 site.  We hope to get that sample chemically “fingerprinted.”  As always, we’ll report the results right here.

Slicks From August 30 – Back Again Today?

Tropical Storm Lee is long gone, the clouds are clearing, and the MODIS/Terra satellite image taken of the Gulf this afternoon seems to show a patch of dark slick located in the same place as the slicks documented by Bonny Schumaker on her August 30 overflight and confirmed on a radar image taken that same day.  The dark patch under the yellow marker is roughly the same size, too, about 14 miles x 5 miles.  And as before, there is no obvious connection between this patch of slick and BP’s Macondo well site.  Maybe it’s coming from something else.  We just don’t know yet.

Weather permitting Bonny may fly out there again tomorrow.

Detail from MODIS / Terra satellite image taken September 9, 2011 showing dark patch in same location as oil slicks observed on August 30.

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.

August 30 Oil Slicks In Gulf – Closest Facilities

Tropical Storm Lee is drenching the Gulf and has put the kibosh on any Gulf Monitoring Consortium investigations for the next few days (even radar satellite images will be screwed up by the heavy rain and gusty winds), so we’ll have to wait and see what next week brings.  In the meantime, one of our Facebook friends (thanks Judson!) prompted us to give a little more info about the oil and gas facilities closest to the August 30 oil slicks (shown as orange dots on this image):

BP’s Horn Mountain platform – located in Mississippi Canyon Block 127 about 8 miles east-southeast of the August 30 slicks, this manned “spar” structure was installed in 2002.  It is connected to the Destin natural gas pipeline system that was shut down on August 30 because it was producing too much liquid.

Exxon’s Mica subsea manifold – located in Mississippi Canyon Block 211 about 8 miles south-southwest of the August 30 slicks.  This structure on the seafloor produces oil and gas that is transported by pipeline to the Pompano platform about 27 miles away.  This “subsalt” discovery marked a milestone in Gulf production.

We don’t have any information that either of these facilities is experiencing any problems, but they are both closer to the August 30 oil slicks than the BP / Deepwater Horizon site, which is about 15 miles away.