Sonic Death: Blasting the Oceans in Pursuit of Oil
"In the darkness of the sea, many species of fish and marine mammals have evolved to rely on sound for navigating, finding food, locating mates, avoiding predators, and communicating. As we continue to develop and industrialize our coasts, we are substantially altering the acoustic environment vital to ocean life." - Michael Jasny (Senior Policy Analyst, NRDC).
Underwater Exploitation:The push to open Florida's coasts to offshore oil drilling brings to light many more issues than just the damage to Florida's white sand beaches and tourism industry. One of the most disturbing of these issues is the destructive scale of ocean floor mapping that is necessary before drillers "break ground" on new projects. The science behind ocean floor mapping is frightening.
To map the ocean floor, the oil and gas industry typically relies on airguns, which fire sonic blasts of up to 260 decibels (db). These airguns are towed behind boats in long arrays, firing shots of compressed air into the water approximately every ten seconds. The intense pulses that they produce travel down through the water column, penetrate the seafloor, and rebound to the surface where they can be analyzed.
These blasts have been called the most intrusive form of man-made undersea noise short of naval warfare, and with good reason.
A 260 db sound is very intense. As a comparison, damage to human hearing starts at 85 db. A police siren from thirty meters is about 100 db. Decibels are logarithmic, meaning every 10 db increase translates into roughly ten times more intensity, and sounds approximately twice as loud to the human ear, which also perceives sound logarithmically. That means the 260 db airgun blast translates to ten quadrillion times more intensity than a police siren at thirty meters, and would sound to humans about 16,384 times as loud.
The threshold at which humans can die from sound alone is 160 db.
A loud indoor rock concert weighs in at around 120 db: whales and other creatures in the Atlantic Ocean and Gulf of Mexico would be subjected to sounds 100 trillion times more intense than that.
Death from sound occurs because sound is a pressure wave. This is why you can feel your body vibrate during loud, low sounds (such as those felt during a concert). Intense waves can rip ear, lung, and other vibrating tissues. They also cause internal bleeding. Two hundred and sixty decibels is 10,000 times more intense than the sound of a nuclear explosion at a range of five hundred meters. Yet, this is what marine life off the coast of Florida will be subjected to in the name of offshore drilling.
It has been well established that the high-intensity pulses produced by airguns can cause a range of impacts on marine mammals, fish, and other marine life, including habitat displacement, disruption of vital behaviors essential to foraging and breeding, loss of biological diversity, beach strandings and mortalities. That's right: whales, dolphins and other marine animals that rely on the ocean for life would rather throw themselves on the beaches than be subjected to this literally deadly noise.
Airgun surveys also have dire consequences for the health of fisheries. Airguns have been known to dramatically reduce catch rates of commercial species over thousands of square kilometers, leading fishermen in some parts of the world to seek industry compensation for their losses. In fact, this is occurring in Norway at the present time.
The Minerals Management Service has made no attempt to account for the impacts of airgun surveys on foraging rates and other essential behaviors in any marine species (including endangered ones). And, unfortunately, the mitigation measures prescribed by the MMS are completely inadequate to redress the environmental harms that the science has identified.
We Need Your Help:
Help us in our call to stop offshore drilling and oil exploration from becoming a reality off Florida's coasts. Here are some things you can do:
Become a Member. We need funding to run our campaigns and to organize citizens across the state. Click here to join.
Write a letter to your elected officials. Simply follow the link below and enter your address. You’ll be able to send an e-mail or a printed letter to your senators, representatives, and the Governor. Contact your elected officials.
Write a letter to the editor. Letters of support to your local newspapers are an easy way to educate the public about offshore drilling and to influence the opinions of local decision-makers. Here is the contact information for several major state newspapers:
The Miami Herald
The Orlando Sentinel
The St. Petersburg Times
The Tallahassee Democrat
Tampa Bay Online
Daytona Beach News Journal
Credits:
Dr. Christopher Clark, director of Cornell’s Bioacoustics Research Program
Derrick Jensen, author of Endgame: The Problem of Civilization
Michael Jasny, Senior Policy Analyst, National Resources Defense Council
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