And the flaring continues off Nigeria…

Looks like flaring on offshore oil and gas platforms in Africa didn’t take a holiday this year. As you can see by this MODIS Aqua 7-2-1 image from  12/23/2012, there was lots and lots of flaring activity going on off the coast of Nigeria.

MODIS Aqua 7-2-1 taken on 12/23/2012 showing multiple flaring incidents off the Nigerian coast.

And not to be outdone, this area where we’ve seen flaring before is at it again:

MODIS Aqua 7-2-1 taken on 12/23/2012 shows an area of flaring that we’ve been following for awhile now.

You can read about that spot off the Niger Delta on our blog post of December 3.We still don’t know who is operating out there, so if anyone knows, fill us in!

Fishing The Line: New Nighttime Satellite Imagery Illuminates Global Fishing Activity

We were wowed like a lot of other folks this week when NASA unveiled the newest “Earth at Night” satellite imagery at the annual AGU fall meeting in San Francisco.  They’ve compiled a bunch of cloud-free, moonless night images collected by the VIIRS sensor onboard the Suomi NPP satellite to create the stunning “Black Marble” vision of Earth at night, the complement to their daytime “Blue Marble” products:

updated 20190219, original image at:

You can explore this neat global dataset in various ways.  Check out an image gallery; play with a handy interactive map; or, my favorite, bring the data into Google Earth, where you can overlay all kinds of other useful data and information to help make sense of what you’re seeing.

So what can you see with nighttime imagery from space?  Well, the lights of cities and towns, of course.  And some other interesting things:  the flaring of natural gas in North Dakota, being treated as a waste product in the Bakken Shale oil-drilling and fracking boom there; flaring offshore too, in the Gulf of Mexico and other locations; fires burning vast areas in Siberia.

And the bright lights of fishing fleets operating around the world. Here’s an example that really caught our eye, in the East China Sea.  The lights from many vessels form a distinct cluster with strikingly sharp, rectilinear edges. I’ve been told this is a real pattern, not a data artifact, possibly revealing “fishing the line” behavior: fishing vessels, armed with GPS navigation systems, are cozying right up to the boundaries of areas where fishing has been restricted or put off limits.These lines don’t seem to match the Exclusive Economic Zone (EEZ) boundaries of Japan, China or Korea. Does anyone know if these patterns we’re seeing really do match up with treaty boundaries or other fisheries agreements?

Black Marble nighttime satellite imagery showing fishing vessel activity in the East China Sea.
[UPDATE 12/07/2012 5pm ET]  A few experts weighed in today via email with some very helpful info, and agreed to let me share their comments (lightly edited).

NASA’s Jesse Allen:

…in short, what you are seeing is ‘aggressive respect for fishing boundaries,’ if I might phrase it that way.

The data we used to make the Black Marble is a composite of several moonless nights in both April and October processed by the NOAA-NGDC in Colorado.  We…mapped that data onto a background colour image and turned plain jane composite light intensity into a colourized map.  So what you are seeing are lights over several different nights in rather different times all added up together at once.
We have noticed… that in many different passes over the Yellow Sea and the general area around the Sea of Japan and the Koreas that there would be boats with lights lined up in what seemed like very unnatural patterns: linear straight lines with sharp corners and such.  If you look here, you can see a less dramatic version of this lining up (in this specific instance, the line they seem to be snuggling along is more of a curved feature).  Those features match up with various fishery boundaries and agreements about respective nation’s areas in shared fishing rights areas (so if you get GIS data for Exclusive Economic Zones, you’ll find that many of these features do not line up with those zones, though some do…)

Steve Miller at Colorado State University:

…because of the current compositing technique done for the Black Marble dataset there are considerably more ship lights than would be seen on any given night…as ships come and go, move around, from night to night you would get “new” points.  From the standpoint of improved sample density, however, it sure helps to outline the political boundaries in more striking detail than any particular night can do!

It’s just another example of how much information content exists in these measurements….and how unique they are from the standpoint of coupling human activity with the natural environment in a way that conventional visible imagery cannot do.
NOAA’s Chris Elvidge:

We have seen these EEZ boundary patterns with fishing boats for 20 years from DMSP.  So it is not surprising or new.  Fishery agencies in Japan, Korea, Peru and Thailand use DMSP data from NGDC to monitor fishing boat activity relative to EEZ boundaries.  Note that the new global cloud-free VIIRS nighttime lights product was produced at NOAA…  NASA wrapped NOAA’s product on a “black marble.”


Chevron No Longer Banned from Operating in Brazil

Remember when Chevron spilled 3,600 barrels of oil when they lost control of an exploratory well in the Frade Field off the coast of Brazil last year? Brazilian Federal Appeals Court judge Guilherme Dienthaeler has overturned the ban in what appears to be a rapid move toward a settlement.

“(Reuters) – Chevron Corp received a boost to its efforts to restart oil output in Brazil after a court overturned a ban on its operating in the country and the company agreed on a plan to improve safety procedures after an oil spill last year.” For the full story, click here.
Aerial view of oil spill in the Frade Field, Campos Basin, Brazil, on November 18, 2011. In the background is the Transocean semisubmersible drill rig operated for Chevron. Photo copyright Marcia Foletto/Agencia O Globo – All rights reserved. 
Chevron and Transocean Ltd. (yes, this Transocean) still face up to $20 billion in damages and some criminal charges, but Federal Prosecutor Eduardo Santo de Oliveria who filed the initial lawsuits is disappointed with the move toward settlement. Reuters quoted Oliveria as saying,”I’m afraid we will lose the chance to apply a giant fine and the good that will do for preventing environmental crime.”

Earlier this year, SkyTruth President John Amos travelled to Natal, Brazil to present our observations at the Brazilian Congress on Protected Areas. For more, click here if your Portuguese is up to par, if not maybe just try Google Translate.

Flaring (?) Off Nigeria’s Coast

We’ve been routinely watching the coast of Nigeria for oil spills (like the recent ExxonMobil offshore pipeline spill that’s affected 20 miles of coastline) and other incidents.  Lately we’ve noticed what appears to be something burning far offshore, approximately 75 miles southwest of Brass on the Niger Delta. We went back as far as July on MODIS satellite images to see what we could find, and we did find evidence of burning going on multiple times over the past few months at that location, as you can see in the images below.

Is this continuous flaring (the burning off of unwanted natural gas) from a deepwater oil production platform, or from a drill rig?  Does anybody know who is currently operating out there?  Any help “sea-truthing” this site would be greatly appreciated!

The location is 3.477568° North latitude, 5.569900° East longitude.

Look for red “hotspots” on MODIS 7-2-1 infrared images, and long smoke plumes on the MODIS True Color images:

Flaring visible on MODIS Terra 7-2-1 on 8/30/12
Flaring visible on MODIS Terra 7-2-1 on 11/4/12


MODIS Terra True Color image 11/16/2012 showing smoke plume extending 100 miles southwest of the flaring site.


Bilge Dumping? Busted Using Satellite Images and AIS Data

Remember that 92-mile-long bilge dump off Congo and Angola that caught our attention back in April?

SkyTruth Angola no markups
Envisat ASAR satellite radar image showing bilge-dump slick (long dark streak) off Angola on April 6, 2012. Image courtesy European Space Agency.

The bright spot at the left end of the slick is likely the vessel that caused it.  But the ASAR imagery left an important question unanswered: Who was responsible for this pollution?

With the generous help of our new partners, SpaceQuest, new information has surfaced that helps put a name on that bright spot:  the Dona Liberta, a refrigerated cargo ship owned by NaviFruit LTD. This vessel has made unfortunate news in the past.  On July 4, 2011, the ship’s captain dumped two Tanzanian stowaways in Liberia’s territorial waters, strapped to empty barrels. One of the stowaways died while receiving medical treatment after washing up on shore. In November 2011 the vessel was laid up in the River Fal in England, stranding two Romanian watchmen on board in unsanitary conditions who were rescued by a charitable organization. And in February 2012, the Dona Liberta spilled 70-90 gallons of oil in the River Fal, prompting a cleanup response from local authorities.

The Dona Liberta, courtesy of © Juan B

So how did we figure this out?

Read all about it after the jump….

In the ASAR satellite radar image, we can determine the exact time and date of the event, the coordinates of the start and end point of the slick, the length of the slick, and the heading of the vessel:

SkyTruth Angola w Markup


SpaceQuest builds satellites that intercept Automatic Identification System (AIS) data broadcast by vessels at sea.  AIS data typically include a vessel’s identification, position, heading and speed. Vessels broadcast this information, and collect it from others, to help avoid collisions with other vessels.  Insurance companies require the use of AIS by most commercial, insured vessels that are underway.  SpaceQuest gave us AIS data for the region spanning a 24-hour period, enabling us to identify vessels that were operating in the area around the same time the radar image was taken. After doing some simple math, we had enough information to pinpoint the likely culprit.



The observed location of the vessel on the radar image is labeled. Red dots show the positions of vessels recorded by AIS data. Red dot at upper left marks the position of the Dona Liberta, 39 miles northwest of observed location of vessel.

AIS data for a vessel 39 miles northwest from the observed location of the ship gave a heading of 293.8° and a speed of 15 knots (17.3 mph), and identified it as the Dona Liberta. This AIS information was broadcast 2.25 hours after the radar image was taken. If the ship traveled for 2.25 hours at 17.3 mph, then the ship traveled 38.925 miles, very close to the measured distance between the observed location and the AIS position.


The heading of the ship was reported by AIS to be 293.8°, only 1.1° off from the measured heading of 294.9°.  I also calculated where the vessel should be, had it been traveling for 2.25 hours at the AIS-recorded heading from the location observed on the satellite imagery. The ship would have ended up only 0.79 miles from the AIS-recorded location. No other vessels appear anywhere near this location on either the radar image, or the AIS data, making the Dona Liberta a likely culprit for this bilge dumping.

Difference between AIS-recorded position of vessel and calculated position based on observed location and AIS-recorded heading and speed.


But a ‘good idea’ of who dumped this material really isn’t good enough. After checking back with SpaceQuest on our findings, they supplemented our data with a compilation of the Dona Liberta’s AIS data for the previous 24 hours. From that, we were able to determine more about the trajectory of this vessel:

Possible route of the Dona Liberta (green line) drawn by simply connecting the red dots (AIS recorded positions). The slick may have drifted southward under the influence of currents and surface wind.

The observed location of the vessel in the radar satellite image was bracketed by two AIS data points, so there was more information available to cross reference with our current suspect. By comparing the time of each AIS point, with the time of the ASAR image, as well as the distance between them, the rate of travel was confirmed:

The green line connects two AIS data points that bracket the observed location of the vessel. Yellow and pink lines are distances calculated from the AIS-reported speed at both points, resulting in predicted positions for the vessel that are nearly identical to the actual observed location on the radar image.

The distance between the eastern AIS position to the observed location (yellow line) is 16.9 miles, and the vessel’s speed according to AIS was 15.1knots (17.377 mph), giving a travel time of 58.4 minutes. The actual time difference between the radar image and the AIS broadcast is 54 minutes. On the other side, the distance between the western AIS point and the observed location (pink line) is 9.66 miles, with the vessel speed at 15.2 knots (17.49 mph), implying a travel time of  33.1 minutes compared with the actual time difference of 36 minutes. These measurements are not exact but are very close, with no other vessels in the vicinity that could be confused with the Dona Liberta.


Bilge dumping is illegal in the United States, Europe and Canada.  We don’t know what the law is governing bilge dumping off Angola. But we’re encouraged that we now have the tools to not only spot this activity, but to identify the likely offenders. And if they don’t care, maybe their insurers and clients will.