Featured Research

from universities, journals, and other organizations

Chemical measurements confirm official estimate of Gulf oil spill rate

Date:
January 9, 2012
Source:
National Oceanic and Atmospheric Administration
Summary:
By combining detailed chemical measurements in the deep ocean, in the oil slick, and in the air, NOAA scientists and academic colleagues have independently estimated how fast gases and oil were leaking during the 2010 Deepwater Horizon oil spill in the Gulf of Mexico. The new chemistry-based spill rate estimate, an average of 11,130 tons of gas and oil compounds per day, is close to the official average leak rate estimate of about 11,350 tons.

A view of the oil source as seen during an overflight on May 20, 2010.
Credit: NOAA

By combining detailed chemical measurements in the deep ocean, in the oil slick, and in the air, NOAA scientists and academic colleagues have independently estimated how fast gases and oil were leaking during the 2010 Deepwater Horizon oil spill in the Gulf of Mexico.

The new chemistry-based spill rate estimate, an average of 11,130 tons of gas and oil compounds per day, is close to the official average leak rate estimate of about 11,350 tons of gas and oil per day (equal to about 59,200 barrels of liquid oil per day).

"This study uses the available chemical data to give a better understanding of what went where, and why," said Thomas Ryerson, Ph.D., a NOAA research chemist and lead author of the study. "The surface and subsurface measurements and analysis provided by our university colleagues were key to this unprecedented approach to understanding an oil spill."

The NOAA-led team did not rely on any of the data used in the original estimates, such as video flow analysis, pipe diameter and fluid flow calculations. "We analyzed a completely separate set of chemical measurements, which independently led us to a very similar leak estimate," Ryerson said.

The new study, Chemical data quantify Deepwater Horizon hydrocarbon flow rate and environmental distribution, was published online January 9 in the journal Proceedings of the National Academy of Sciences.

The new analysis follows on another NOAA-led study published last year, in which Ryerson and colleagues estimated a lower limit to the Deepwater Horizon leak rate based on two days of airborne data collected during the spill and the chemical makeup of the reservoir gas and oil determined before the spill. The new analysis adds in many other sources of data, including subsurface and surface samples taken during six weeks of the spill and including a direct measure of the makeup of the gas and oil actually leaking into the Gulf.

Ryerson and his colleagues found that the leaking gas and oil quickly separated into three major pools: the underwater plume about 3,300-4,300 feet below the surface, the visible surface slick, and an airborne plume of evaporating chemicals. Each pool had a very different chemical composition.

The underwater plume was enhanced in gases known to dissolve readily in water, the team found. This included essentially all of the lightweight methane (natural gas) and benzene (a known carcinogen) present in the spilling reservoir fluid. The surface oil slick was dominated by the heaviest and stickiest components, which neither dissolved in seawater nor evaporated into the air. And the airborne plume of chemicals contained a wide mixture of intermediate-weight components of the spilled gas and oil.

The visible surface slick represented about 15 percent of the total leaked gas and oil; the airborne plume accounted for about another 7 percent. About 36 percent remained in a deep underwater plume, and 17 percent was recovered directly to the surface through a marine riser. The location of the balance, about 25 percent of the total, is not directly accounted for by the chemical data.

This information about the transport and fate of different components of the spilled gas and oil mixture could help resource managers and others trying to understand environmental exposure levels.

The chemical measurements made from mid-May through June showed that the composition of the atmospheric plume changed very little, suggesting little change in the makeup of the leaking gas and oil.

The team of researchers also used the detailed chemical measurements to calculate how much gas and oil, in total, was spilling from the breached reservoir deep underwater. The new chemistry-based estimate of 11,130 tons per day has an estimated range of 8,900 to 13,300 tons per day. By comparison, the official estimated range was 10,000 to 12,700 tons per day.


Story Source:

The above story is based on materials provided by National Oceanic and Atmospheric Administration. Note: Materials may be edited for content and length.


Cite This Page:

National Oceanic and Atmospheric Administration. "Chemical measurements confirm official estimate of Gulf oil spill rate." ScienceDaily. ScienceDaily, 9 January 2012. <www.sciencedaily.com/releases/2012/01/120109155712.htm>.
National Oceanic and Atmospheric Administration. (2012, January 9). Chemical measurements confirm official estimate of Gulf oil spill rate. ScienceDaily. Retrieved July 26, 2014 from www.sciencedaily.com/releases/2012/01/120109155712.htm
National Oceanic and Atmospheric Administration. "Chemical measurements confirm official estimate of Gulf oil spill rate." ScienceDaily. www.sciencedaily.com/releases/2012/01/120109155712.htm (accessed July 26, 2014).

Share This




More Earth & Climate News

Saturday, July 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Virginia Governor Tours Tornado Aftermath

Virginia Governor Tours Tornado Aftermath

AP (July 25, 2014) Virginia Gov. Terry McAuliffe toured the Cherrystone Family Camping and RV Resort on the Chesapeake Bay today, a day after it was hit by a tornado. The storm claimed two lives and injured dozens of others. (July 25) Video provided by AP
Powered by NewsLook.com
Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
Goma Cheese Brings Whiff of New Hope to DRC

Goma Cheese Brings Whiff of New Hope to DRC

Reuters - Business Video Online (July 24, 2014) The eastern region of the Democratic Republic of Congo, mainly known for conflict and instability, is an unlikely place for the production of fine cheese. But a farm in the village of Masisi, in North Kivu is slowly transforming perceptions of the area. Known simply as Goma cheese, the Congolese version of Dutch gouda has gained popularity through out the region. Ciara Sutton reports. Video provided by Reuters
Powered by NewsLook.com
Bill Gates: Health, Agriculture Key to Africa's Development

Bill Gates: Health, Agriculture Key to Africa's Development

AFP (July 24, 2014) Health and agriculture development are key if African countries are to overcome poverty and grow, US software billionaire Bill Gates said Thursday, as he received an honourary degree in Ethiopia. Duration: 00:36 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

More Coverage


Comprehensive Picture of the Fate of Oil from Deepwater Horizon Spill

Jan. 10, 2012 A new study provides the composite picture of the environmental distribution of oil and gas from the 2010 Deepwater Horizon spill in the Gulf of Mexico. It amasses a vast collection of available ... read more
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins