In Situ Burning (ISB) or controlled burning has been one of the main responses to spills in the USA Mexican Gulf region since 1994.
Unfortunately when BP's Deepwater Horizon sank the paperwork was in place but the booms and auxillary equipment were not.
Controlled burning at sea
Some countries in
The thought process for the operation with fire booms is not simple. We have to be alert to the fact that we are going to transform the hydrocarbons originally in a liquid phase, into a gaseous phase.
The validation of the purchase of an equipment of this type is justified by the risk of imminent danger that an activity could pose, for example, if we have an oil fire in a maritime terminal, this type of boom allows us to protect other ships and property from the burning oil.
Oil with a thickness of 2 - 3 mm is necessary to initiate the burn. Thinner than this, oil is cooled by the temperature of the sea water and therefore will not burn. The technique is to move the boom in order to better concentrate the oil to ideal thickness in the apex.This factor is also a safety point when involved with an in-situ burn. We can slow the speed of the vessels to burn the oil in the boom with large quantities burning the fire moves towards the mouth of the boom. This can be worrying for an inexperienced crew as the flames are approx. 20m high and the sound is like an enormous chip pan. Control is maintained by moving forward slightly faster thus allowing oil to entrain under the boom thus reducing the thickness, the fire will also diminish. If we continue the fire will go out.
We may initiate the burn with the use of an ignition system used in the USA by the forestry departments to burn fire breaks in front of wild fires known as a Helitorch© it is under slung from a helicopter. The systems are manufactured in the USA and comply with FAA regulations in
Left is a hand held ignition systems using gelled fuel with a hand held flare as the ignition have been used successfully for many years. In cases of more weathered oil flammable materials may also be used, such as gasoline or kerosene to ignite and propagate the flames.
See Deepwater Horizon section below for diesel instead of gasoline.
In areas far from the coast, burning may be considered a satisfactory method. According to the degree of weathering of the oil, the more volatile components are rapidly lost due to evaporation. This aspect, together with the process of the slick spreading on the surface of the sea, makes the burn a progressively less effective method or in some cases impossible. We should do the burn with fresh oil.
With the passage of time, the combustible gradually loses its more volatile and ignitable components. Emulsions of up to 25% water have been burnt successfully.
During the North Sea trail 1996, we tried using a emulsion breaking formula (Sintef) but found it needed 12-15 times as much gelling agent than for normal gasoline. It was also difficult to mix without getting lumps which would then block the helitorch system.
Field testing has already demonstrated efficiencies of up to 98% of the burn a small amount of toffee like residue is left.(photo left shows residue after a burn on the north slope in 2000)
The technique shows a better response than mechanical containment or use of chemical dispersants, besides generating less residues and being the least expensive of the techniques in certain circumstances.
It has to be pointed out that the spilled oil, sooner or later, will be burned anyway. Studies have shown that a burn a few kilometres from the cities and villages does not constitute a significant environmental or public health problem.
Weather forecasting is extremely important so we know the wind will not shift and endanger local populations.
There is still much reluctance to use this technique. The burn could also be exploited by a sensationalistic press. This technique is more and more acceptable and is an excellent option, if we take into consideration the environmental variables.
Below are some photos of sea trials that were carried out in Norway, Newfoundland and the North Sea to evaluate the technique and a rare photo of the actual first time burning was used at a spill was during the Exxon Valdez incident. This was stopped due to public outcry over the smell.
Spitzbergen 1988 Exxon Valdez 1989
Newfoundland NOBI August 1993 North Sea June 1996
In-situ burning has been studied under controlled conditions in laboratories and in field tests, and recently under realistic conditions in an experiment off the coast of Newfoundland, Canada. This experience indicated that in-situ burning can be an effective oil-removing technique, removing 50% to 99% of the oil collected in the boom. In addition, a field "real" burn conducted in the first days of the Exxon Valdez spill in Prince William Sound, Alaska, resulted in the burning of 15,000 to 30,000 gallons of Prudhoe Bay crude oil at an estimated efficiency of 98% or better (Allen 1990).
Before I start this section I have to say that I take the remark made by Captain Paul Watson of the Sea Shepherd Conservation Society (right) on Larry King Live, saying that we were burning the bodies of dolphins and turtles at night, as a personal insult as well as being completely unfounded.
This blow out in the Gulf of Mexico in 20th April 2010 became the first opportunity for the response option of in-situ burning of oil at sea to become a major response strategy after over 30 years of trying.
411 burns were carried out which removed 5% or over 300,000 Barrels of oil, during the same time all the skimming operations removed 3% proving when conditions are right this is a very useful strategy.
Photo left shows an in-situ burn was carried out in the first week after the sinking of the rig to prove the strategy would work, having burned the oil in the boom, permission was given for a full scale operation.
This took a couple of weeks as there was only one boom readily available at a manufacture in the USA. Fire resistant boom had to be located and moved to Venice, Louisiana.
Various types of fire boom were found in Alaska, Algeria, Brazil.
The booms were loaded aboard vessels and taken to the area 3 nautical miles NNE of the position where the rig had sunk. Shrimp fishing boats without their out riggers were hired as tow vessels. Training these captains how to manouver with the booms was critical to the strategy.
I was part of this offshore response where we tried old and new techniques to get the best out of the strategy.
Even though the well continued to flow fresh oil, it did not come up to the surface in sufficient quantities every day. When we had good quantities we burned very good amounts and proved that the strategy in these sea conditions was much better than the containment and recovery (Boom and skimmers) strategy.
During the period BP tried the top kill by pumping mud into the well, the flow reduced drastically and on one day we found no oil to burn. On some days we would have as many as 17 burns on others that would be down to 1.Quote Neré Mabile (Controlled burn technical advisor)
We use each area/duration segment for a burn and do a max/min calculation based on relatively fresh oil one might find near its source (which is where we work each day)and on an emulsion where the oil has been weathered downstream of its source. We use 0.07 gpm/sqft burn rate for a max. calc., and 0.05 for assuming we have emulsified oil.
These two burn rates have been used for years and are generally accepted as conservative burn rates. Actually, a fresh crude oil could burn even faster than the 0.07 gpm/sqft rate.
We sum up all the space/time segments of a burn for each of the max/min values.
Estimates are derived based on the conditions at the time and the estimates of personnel on site, one could make rough calculations the fall somewhere in the neighborhood of the max/min bbl. After a burn day, we collate area and duration observed from the air, from personnel observing from support vessels and the small igniter boats who are closest to the operations. This methodology, we feel is the best in practice.
(The charts we used are shown below in the Practical part of this section).
During the period 28/04/10 – 11/06/10 166 fires burned between 78,988 to 112,136 barrels.
On the 18th of June alone, an estimated 50,000 to 70,000 barrels of oil was removed.
The major problem we encountered was when they pumped dispersant into the oil at the leak source. This turned the oil on the surface red or orange and made it impossible to burn due to the high water content in the oil.
In the past plastic bottles with gelled petrol (gasoline) with a marine flare had been used. We were not allowed to take petrol offshore and so when you have to get the job done you come up with other methods like gelled diesel which was used instead and in truth was much safer than those methods used during the trials in the 1990's.
To get an area of sufficient heat to ignite this type of crude oil it was found that 2x1/2 gallon plastic milk bottles taped together with foam to float the igniter and a marine flare worked well. When the oil had weathered, we used half of an absorbent boom coiled and soaked with diesel and the igniter placed on top.
Marine flare taped in position Flare between milk bottles and taped together Igniter on fire in black oil
It was found that when black oil could be ignited and with a good sized fire, emulsified oil entering the boom would burn if the towing vessels slowed to allow the water phase to be evaporated first leaving just the oil, as shown in this photo (right) I borrowed from the Elastec site. The fire is burning black oil and is not spreading across the emulsion but as the water will evaporates then the oil burns.
If the emulsion entered too quickly the fire would be put out.
4 different manufactures fire booms were used, some burned once and sank where as others worked for 5 days and burned oil on 6 - 16 different occasions.
The list below is a true account of what happened while I was there and is not designed to favour one manufacturer over another. All of the booms were treated the same during this response. Some performed better than others in this first real world opportunity to test this strategy.
There is a shortage of these types of boom in the world and so to get as many burns as possible from each boom was the main aim.
Air cooled, stored on reels for easy deployment and recovery.
3 different booms were used, all of which burned once then started to sink after suffering serious damage.
Before During After
Fire proof material with steel ball floats.
Only 1 x 100 foot section was used as this was all that was all that was available from the manufacturer in the USA at the time. This burned oil on 5 occasions and was removed from the operation only when the fire resistant material had been burned to such a degree that the oil flowed though the apex of the boom. A further 7,000 feet in Algeria, North Africa was flown in after I returned home.
Before During After
Float section stainless steel mesh with heat resistant pumis stone. The majority of this boom had been stored in containers of 500 feet in Alaska for over 15 years. 3 different generations were used and it was found that the newer version was the best.
This diagram shows the component parts, the plastic burns off to the water line during the burn and with the earlier versions so do the nylon hand holds.
We used 2 different versions which came from Alaska.
Following the very successful operation in the Gulf of Mexico during 2010 this boom now known as American Fireboom has been brought back into production.
Although this boom cannot be put on a reel which makes it bulky for storage, it does provide a straightforward option without requiring support systems such as reels, powerpacks, air blowers and water pumps.
After the North Sea burn 1996, 4 of us removed 400 feet of this boom by hand from the sea into a rubbish skip. It needs to be said that a crane is neccesary from a health and safety stand point.
Before During After
Elastec Hydrofire boom:
Water cooled stored on reels for easy deployment and recovery.
It was found that they required more water than they were originally designed for, pumps were doubled up and another 2 pumps were hired. Spare air bladders were available to keep these booms working.
We managed to burn more oil with this boom basically because we could interchange sections with undamaged ones.
Some of the Brazilian booms had suffered damage during there 6 year storage, from the climate and insects. Though it was easier to make running repairs than the other types.
The diagram left shows the component parts.
With the experience gained here, the boom and pumps have been upgraded.
Before During After
During this operation all of the different types of boom were given a fair chance to show how well they could stand up to the job. We plated 3" absorbent boom to fill any gaps where oil could leak out before we could ignite it. This was to make them last as long as possible because we were still waiting for more to arrive at the port.
I know there are other fire booms on the market but I can only give you information about the one's we used.
The booms worked well in the calm waters of the Mexican Gulf, I think they need to be made bigger for other sea areas as they would not work everywhere in the world, the freeboard of these booms is low in comparison with normal offshore booms. Obviously this will also increase the cost of the equipment.
These burns were extremely hot as can be seen by the melted aluminium connector. The melting point of Aluminum is recorded to be 660.37 °C or 1220.666 °F
Smoke plumes and personnel safety
It has to be mentioned that safety was always a high priority during this operation and that it was a good opportunity to show the world that this is a safe strategy.
To that end the photographs show the proximity to the fires the shrimp boats and other personnel involved. Just speeding up the towing vessels would allow the oil to escape and go out.
The heat generated by the burning oil in the boom (1800 °F were measured at the top of the boom at the Newfoundland NOBE burn) will cause the smoke to rise several hundred to several thousand feet, and at the same time be carried away by the prevailing winds.
In areas having well-developed sea-breeze systems, plume fumigation and recycling may draw the smoke toward the surface. It is expected that the plume will be high enough to stay out of the sea-breeze/land-breeze circulation cell. The smoke plume at the in-situ burning conducted off Newfoundland and at marsh and brush burns leveled off at several hundred feet, and then lofted slowly over distance. The upper boundary of the plume often extends to an altitude of several thousand feet. The main plume may also split into two or more smaller plumes, each heading in different directions.
We did on occasions have huge fires out side the booms which continued to drift and burn drawing oil from 360º around them. The photo right is the first of the long burns this one removed an estimated 16,000 barrels in just under 4 hours.
Before all burns the current and wind were taken into consideration so as not to have smoke near the tow vessels but also to be able to use the current to feed the fire with fresh oil. Air monitoring was carried out every day during burns.
Data from previous measurements done during test burns:
Particulates seem to be of major concern, as their concentration in the center of the plume remains above the level of concern for the general population for several miles downwing. These particulates concentration under the plume do not significantly exceeds background levels. Protection of response personnel can be achieved by adequate training and personal protective equipment.The general public can be protected by establishing guidelines that will prevent the burn from becoming a health hazard to the public. When compared to conventional response methods and beach cleanup, in-situ burning can reduce the number of people required to clean the beaches and reduce the injuries associated with this work.
Eliminating oil at the source of the spill, can reduce its contact with marine birds and mammals.
Burning can minimise beach impact and reduce the waste generated.
While generating substantial amounts of combustion by-products, mainly CO2, water, and particulates, burning reduces the amount of evaporation of toxic elements.
Burning oil has the potential to reduce the impact of oil spills, and since the risk it poses to the responders and to the population downwind are, under most circumstances are acceptable, it should be one of the response options available for future oil spills.
The main health problems would come from the following;
Extract from: Health and Safety Aspects of In-situ Burning of Oil, Nir Barnea, National Oceanic and Atmospheric Administration
After the NOBE trial in Newfoundland 1993.
Carbon monoxide (CO)
Sulfur dioxide (SO2)
Nitrogen dioxide (NO2)
Polynuclear aromatic hydrocarbons (PAHs)
Particulates (soot, dust, etc)
Carbonyls (aldehydes and ketones)
volatile organic compounds (VOCs) Photo: NOBE Plume data collectingCarbon monoxide (CO)
This is a common by-product of incomplete combustion. The toxicity of CO is acute and stems from its high affinity to the hemoglobin molecule in red blood cells. CO will chemically displace oxygen from the blood and cause oxygen deprivation in the cells of the body. During burns the average level of CO in the smoke plume over the duration of the burns 15 to 30 mins are found to be 1 to 5 ppm 150 meters downwind (Fingas et al. 1993).
Sulfur dioxide (SO2)
This is a gas formed when sulfur in the oil or hydrogen sulfide oxidize during combustion. This gas is toxic and irritates eyes and the respiratory tract by forming sulfuric acid on these moist surfaces (Amdur 86). The concentration of SO2 in the smoke plume depends on the sulfur content of the oil. Average SO2 levels during burns are normally below 2 ppm in the plume 100-200 meters downwind of the burn (Fingas et al.1993). Several miles downwind, sulfur dioxide from burn is normally well below the level of concern.
Nitrogen dioxide (NO2)
Another toxic gaseous by-product of oil combustion. Like SO2, is a strong irritant to the eyes and respiratory tract. NO2 is less soluble than SO2 and therefore may reach the deep portions of the lungs so that even low concentrations may cause pulmonary edema (Amdur 1986). Sampling results to date indicate that concentration of nitrogen dioxide in the plume several miles downwind of the burn do not exceed several parts per billion (Ferek 1994). It is not expected to pose a threat to the general public several miles downwind of the burn.
Polynuclear aromatic hydrocarbons (PAHs)
These are found in the unburned oil as well as the smoke plume. Some PAHs are known or suspected to be carcinogens.
Target organs may include the skin (from chronic skin contact with oils) or the lungs from inhalation of aerosol.
Considering the low levels detected so far, it is felt that they present only a small exposure hazard.
The PAH concentrations in the smoke, both in the plume and the particulate precipitation at ground level, are much less than in the starting oil. This includes the concentration of multi-ringed PAHs. There is a slight increase in the concentration of multi-ringed PAHs in the burn residue. When considering the mass balance of the burn, however, most of the five and six-ringed PAHs are destroyed by the fire.
(Fingas et al. 2013)
Most health professionals consider to be the most problematic combustion product. Particulates are small pieces of solid materials (dusts, soot, fumes) or liquid material (mists, fogs, sprays) that remain suspended in the air long enough to be inhaled.
During burns elemental carbon (soot) and hydrocarbons are emitted.Depending on pore size, the filter may collect more than 99.9 percent of the particulates in the air.
They are calibrated to the particulates of concern, since 10 micrometers (mm) in diameter and below is the size which may be inhaled and cause respiratory problems. “PM-10,” which is the fraction of particulates smaller than 10 mm in diameter. Particles greater than 10 mm in diameter are removed at the nose and upper portion of the respiratory tract.
Particles 5 to 10 mm in diameter would be deposited in the bronchi.Only particles smaller than 5 mm will actually be deposited in the alveoli, where gas exchange takes place.
The median size of the particulates reaching the alveoli is approx. 0.5 mm.Particulate size also plays role in determining how long they will be suspended in the air.The variable concentration of PM-10 in the smoke plume. In some spots within plume the amount of particulates may exceed 150 mg/m3 even 10 miles downwind.
It has been found that PM-10 concentration beneath the plume, 150-200 feet above the surface, does not exceed background levels of 30 to 40 mg/m3 (Ferek personal communication 1994 ).
This operation took place approximately 50 miles away from the coast and so there would be no health problems encountered with the local population.
Though with the obscene amount of lawyers out there trying to make money for themselves and some for the local population I am sure they would try to prove otherwise.
All burns, especially those of diesel fuel, produce an abundance of particulate matter. Particulate matter at ground level is a health concern close to the fire and under the plume. Particulate matter is distributed exponentially downwind from the fire.
Many volatile organic compounds are emitted by fires, but in lesser quantity than when the oil is not burning. VOCs are not typically a concern, but can rise almost to health levels of concern very close to the fire.
Organic Compounds No exotic or highly toxic compounds are generated as a result of the combustion process. Organic macromolecules
are in lesser concentration in the smoke and downwind than they are in the oil itself. Dioxins and dibenzofurans have not been measured as emissions of oil fires to date.
Carbonyls such as aldehydes and ketones are created by oil fires, but do not exceed health concern levels even very close to fires.
Here is a close up of what goes on behind the scene. The oil coming to the surface was different nearly every day as can be seen from the photo's. The more orange looking the greated the water content in the oil emulsion.
Oil Emulsifing as above will not burn on it's own, there is a need to find brown or black oil to start the fire then allow the emulsified oil drift into the fire with the current. If black or brown oil cannot be found then the emulsion will go to the shoreline.
Sometimes mother nature gives you a hint as to where the thick black oil is. This is what is needed to make a difference as far as how much oil will go ashore.
Rain can help as the splash from the rain drops is removed by the oil and a smooth and shiny area is easy to see.
The small igniter boats were used to drive through the thicker oil, allowing the shrimp boat captains to follow the line of oil.
As can be seen at sea level photo right without seeing the oil in the wake of the boat igniter the sea looks blue and clear of oil.
These forms were taken from an Al A Allen lecture pdf about the burning at Deepwater Horizon.
Having got the oil into the boom, permission has to be granted from the Incident Command ashore before ignition takes place. This was done through the Burn Coordinator and the Coastguard aboard the fleet's mother vessel.
The longtitude and latitude, burn team number has to be sent and during the burn these forms have to be filled in so that the calculations can be done by the Incident Command.
Having got permission to burn the igniter boat positions itself at the place where the most black oil is in the boom this may differ from burn to burn dependent on the oil and any wave action.
The flare is activated and allowed to burn for a few seconds to become intense then it is drawn back in between the plastic bottles. It is then places in the oil, the flare burns through the plastic releasing the gelled diesel to flow into a patch where it burns and starts to evaporate the flammable parts of the crude oil. This may take up to 10 minutes dependent on the oil.
The Burn Coordinator is informed when the actual crude oil is ignited and a log is kept for the duration of the burn. It may start small then grow in size then shrink again.
Photo right shows oil jumped over the boom and continue burning, these fires would bring in oil from 360 degrees but were controllable, running a boat around them a couple of times would cut of the supply of oil and they would go out.
We would usually let them burn as every barrel burned was one less to impact the shoreline.
The size and duration of each fire has to be noted to get the best results from the final calculation.
Collecting this data requires people to be faily close to the burn. Safety is aways the prime concern but even with the big fires the heat is bearable at 200 to 300 feet from the fire. We used the smoke to give us shade from the sun as it blocked it out completely.
The residue left at the end of the burn is always different sometimes it is a thick black tarry substance, here the oil was more emulsified so the amount of residue is greater and orange.
During this burn due to the lack of sufficient oil in one area, the shrimp boats made 360° turns without letting the fire out.
Teamwork is the key and the more time spent doing the job makes people better at it. When things go right, burns lasted from 20 minutes to the longest of nearly 12 hour.
In order to make the operation more efficient we broke the shrimp boats into groups with a command vessel, 4 shrimp boats and 1 or 2 igniter boats.
The photo left shows my group of 4 shrimp boats (Mr Jug and Capt Craig distant right, Big Bad Brad and Miss Yvette front left with the small igniter boat with a crew of 2 who reported the percentage of oil in the booms for both groups of boats and ignited the oil when enough was available. The team command vessel was the Coastal Mariner on the right edge of photo.
The overall command vessel and mother ship of the task force the Premier Explorer was where permission had be gained for a burn to happen.
All information about each burn was passed to the coordinator who in turn passed it to the Command centre in Houma, Louisiana
The photo right is the result of good teamwork, experience as well as a good oil on the surface.
The majority of these fires are outside the booms but can still be controlled by the team.
This spill happened during the nesting season for many birds as well as the spawning season for shellfish along the Louisiana shoreline so the damage to them could have been much worse had this strategy not been used.
These areas produce 33% of the US oysters and shrimps.
98% of the fish, shrimp and oysters depend on this area. (National Geographic oct 2010)
Many people have complained about the smoke and the air pollution that comes with it.
Photo June 18th 2010 between 50,000- 70,000 barrels burned
It has to be said that the USA burns 20 million barrels of oil per day! (National Geographic oct 2010) so this air pollution is a few hours of a normal day!
Final results yellow minimum green maximum oil burned
With the amount of fires out of the boom being fed from 360 degrees not just in the boom configuration, the amounts on some days could have been much more than was recorded.
The table below was extracted from an excellent article on in-situ burning by Dr Merv Fingas of Spill Science in The Newsletter of the International Spill Response Community (ISCO) link http://www.spillcontrol.org/Joomla/
Issue 367, 14 January 2013
This table provides generalizations about the burning of various fuels:
It was a great experience being involved in this operation which wasthe first time IBS was used as a principle strategy during an oil spill response.
Working in a small team with good people, most from very different backgrounds with one common aim is rare but when it happens it is something very special.
Thank you Donnie for the opportunity and the T Shirt.
Videos available on the internet
BP have posted two videos on their website;
Here is another burn video posted by the participants
NOAA researchers release study on emissions from BP/Deepwater Horizon controlled burns
September 20, 2011
During the 2010 BP/Deepwater Horizon Gulf oil spill, an estimated one of every 20 barrels of spilled oil was deliberately burned off to reduce the size of surface oil slicks and minimize impacts of oil on sensitive shoreline ecosystems and marine life. In response to the spill, NOAA quickly redirected its WP-3D research aircraft to survey the atmosphere above the spill site in June. During a flight through one of the black plumes, scientists used sophisticated instrumentation on board, including NOAA's single-particle soot photometer, to characterize individual black carbon particles.
The black smoke that rose from the water’s surface during the controlled burns pumped more than 1 million pounds of black carbon (soot) pollution into the atmosphere, according to a new study published last week by researchers at NOAA and its Cooperative Institute for Research in Environmental Sciences (CIRES) in Boulder, Colo.
This amount is roughly equal to the total black carbon emissions normally released by all ships that travel the Gulf of Mexico during a 9-week period, scientists noted.
Black carbon, whose primary component is often called soot, is known to degrade air quality and contribute to warming of the Earth’s atmosphere. The new study, published online in Geophysical Research Letters, provides some of the most detailed observations made of black carbon sent airborne by burning surface oil.
“Scientists have wanted to know more about how much black carbon pollution comes from controlled burning and the physical and chemical properties of that pollution. Now we know a lot more,” said lead author Anne Perring, a scientist with CIRES and the Chemical Sciences Division of NOAA’s Earth System Research Laboratory (ESRL) in Boulder, Colo.
Black carbon is the most light-absorbing airborne particle in the atmosphere and the reason for the black color in the smoky plumes that rise from the surface oil fires. Black carbon can also cause warming of the atmosphere by absorbing light. Prolonged exposure to breathing black carbon particles from human and natural burning sources is known to cause human health effects.
During the 9 weeks active surface oil burning, a total of 1.4 to 4.6 million pounds (0.63 to 2.07 million kilograms) of black carbon was sent into the atmosphere of the Gulf of Mexico, the study estimated.
The study found that the hot soot plumes from the controlled burns reached much higher into the atmosphere than ship emissions normally rise, potentially prolonging the amount of time the black carbon can remain in the atmosphere, which would affect where the black carbon ends up.
The researchers also found that the average size of the black carbon particles was much larger than that emitted from other sources in the Gulf region, and that the emitted particles produced were almost all black carbon, unlike other sources such as forest fires that tend to produce other particles along with black carbon.
“The size and makeup of the black carbon particles determine how fast the particles are removed from the atmosphere by various processes, which ultimately affects their impact on climate,” says Perring. Larger particles are removed from the atmosphere more quickly and thus have smaller climate impacts. And, those same properties of black carbon are important for assessing human health impacts.
Finally, Perring and her colleagues found that of the oil that was burned, 4 percent of the mass was released as black carbon, an important metric rarely observed during cleanup of an oceanic oil spill, which could help guide future decision-making.
The new paper, Characteristics of Black Carbon Aerosol from a Surface Oil Burn During the Deepwater Horizon Oil Spill, has 15 co-authors from NOAA ESRL and CIRES and can be found on the Geophysical Research Letters website.
NOAA OAR’s Oil Spill Research (Deepwater Horizon)
Air Chemistry Assessments
Investigating smoke and pollutants in the Gulf
As a part of a multi-agency response to the Deepwater Horizon spill, OAR conducted an air quality assessment of samples taken during June, when oil was actively flowing from the well. A hurricane hunter aircraft equipped with sensitive air quality sampling instruments collected samples near and downstream from the spill area from lower layers of the atmosphere typically where pollutants are trapped. Compared to areas relatively unaffected by the spill, concentrations of certain hydrocarbons in areas 9.3 to 43.5 miles downwind from the spill were much higher than those in typical polluted air.
Large amounts of black carbon were identified in smoke from a controlled burn. Nearshoreareas 18.6 to 24.0 miles from shore were generally lower in concentration of pollutants than those typically found in urban areas.
Photo right air pollution New York, USA.
From a research perspective, these data inform NOAA's air quality modeling associated with the Deepwater Horizon oil spill, and complemented air monitoring on ships in the vicinity of the oil spill as well as EPA's ASPECT air quality surveillance airplane mission.