ENVIRONMENT
Thousands of invisible oil spills are polluting the Gulf of Mexico. (WIRED)
Navigate the geography of offshore oil in the Gulf of Mexico with our dazzling high-res map.

Map by William E. McNulty, National Geographic
Discussion Ideas
- Why are oil spills invisible?
- They’re not. What WIRED calls “invisible” is not unsee-able, just low-profile; we don’t hear about them the way we do the Deepwater Horizon or Exxon Valdez spills.
- The “Coast Guard classifies many spills—up to 100,000 gallons—as minor or moderate, and small spills get less of everything: less media attention, less regulation, less environmental impact assessment, and most critically, less funding to clean them up.”
- How do oil spills happen?
- Oil spills are a result of both natural and human activity.
- Natural
- geology. Natural seeps are gradual releases of petroleum from the seafloor. Seeps have been occurring for thousands of years, long before people began to drill for energy-rich fossil fuels. Natural oil slicks are shallow, and some organisms (bacteria and archaea) have actually evolved to live in the toxic ecosystem.
- Human Activity
- aging infrastructure. Updating and maintaining oil extraction equipment is incredibly expensive, and many energy companies do not invest in updating or performing rigorous tests of their equipment.
- abandoned wells and rigs. Although hundreds of wells sit technically empty, “oil is still hanging out in the reservoir or the pipes connected to” them.
- human error. The enormous demand for oil drives energy companies to set high goals for oil rigs and wells. This often leads to ignoring safety and environmental standards.
- engineering. Many oil rigs (such as the Deepwater Horizon) are in very deep water, under incredible pressure, and far from land-based emergency responders. Petroleum engineers have their work cut out for them.
- Both. Sometimes, natural factors can augment weaknesses introduced by people. The WIRED article begins with describing how a hurricane created an underwater mudslide, which then “created leaks in 25 undersea oil wells, snarled the pipelines leading from the wells to a nearby oil platform, and brought the platform down on top of all of it. And a bunch of the mess … is still down there, covered by tons of silty sediment. Also, twelve years later, the mess is still leaking.”
- Natural
- Oil spills are a result of both natural and human activity.
- How can seemingly tiny oil spills impact the environment?
- According to WIRED, “Air-breathing animals like dolphins and turtles suck in oil if they surface in a slick, and when even small amounts of oil end up in their lungs, they suffer fatal pneumonia-esque health issues. Plants and algae can’t photosynthesize under a grungy film. And even a few molecules of oil can kill fish larvae.
- “Human physiology isn’t a fan either. ‘Oil slicks can be very noxious. My graduate students have become ill from the fumes when we’ve gone out there,’ says one oceanographer.”
- Small spills add up. WIRED estimates that at least 30,000 gallons of oil leak into the Gulf of Mexico each year—and more gallons go unreported due to old or inefficient equipment.
- How do scientists estimate the size of oil spills?
- Business. Energy companies monitor their own spills relying primarily on aerial observation. They report this figure to the government. The Coast Guard puts the energy companies on the honor system and levies fees based on these numbers, which critics say creates a conflict of interest. (The lower the reported number, the lower the fine—and there are no penalties for underreporting.)
- Science. Scientists and environmental groups use satellite imagery and remote imaging to estimate the size of an oil slick. They compare this estimate with the estimate provided by the energy companies—and, one scientist notes, “the numbers don’t add up.” Environmental groups report up to 13 times the amount of oil spilled as energy companies.
- n/a. Many spills are simply not reported. In particular, WIRED notes, the 2.4 million miles of pipeline criss-crossing the U.S. are often ignored. “There’s so much infrastructure and no one monitoring it,” says one environmentalist.
TEACHERS TOOLKIT
WIRED: Thousands of Invisible Oil Spills Are Destroying the Gulf
Nat Geo: Gulf of Mexico—A Geography of Offshore Oil map
Nat Geo: What is petroleum?
3 thoughts on “Are Invisible Oil Spills Destroying the Gulf of Mexico?”