Offshore Drilling Part 1: What Is It, and Its Impacts on the Marine Ecosystem
I had started writing about the Arctic offshore drilling happening right now off the coasts of Alaska, but as I rambled on and on, I figured I needed to first start by explaining what offshore drilling is, and what it does to the marine environment.
- What Is Offshore Drilling?
We consume more than 93 million barrels of oil every day worldwide. To meet our ravenous demand for fossil fuels, petroleum companies constantly comb the planet for new reserves, and a vast majority of these resources are under the oceans.
Most of the world’s petroleum is trapped between 500 and 25,000 feet (152 and 7,620 meters) under dirt and rock. How did it all get there? All this oil actually began as plankton, which died in the ancient seas between 10 and 600 million years ago. This decaying matter drifted to the bottom of the ocean, and over time was covered with sand and mud. Without oxygen, and millions of years of heat and pressure, this organic material eventually transformed into vast deposits of liquid, gas and solid petroleum, all capped in traps under thick layers of rock.
Offshore platforms are giant structures used for the purpose of drilling and extracting these gas and oil from wells, located deep beneath the ocean floors. They are strongly built and are designed to last decades in the harsh environment. Depending on the requirements, they can either be floating or fixed to the ocean floor.
Nowadays, modern oil rigs are gigantic floating cities, employing and housing hundreds of people. Some go down to the bottom at depths of over 4,000 feet (1,200 meters).
- How Does Offshore Drilling Affect the Environment?
Seismic blasting - Offshore drilling has a number of negative impacts on our environment. First of all, you have to find the oil. One of the ways to find the oil is through the use of seismic surveying. This method involves sending shock waves down through the water and into the ocean floor. With the aid of computers, seismologists can then analyze the shock wave results to pinpoint possible oil locations in the ocean floor.
Survey ships use both compressed air guns and explosives to emit shock waves. However, this kind of acoustic pollution poses a threat to seismically aware sea animals such as the endangered blue whale, and to other marine mammals relying heavily on marine echolocation. The incredibly loud blasts have also been found to damage or kill fish eggs and larvae and to impair the hearing and health of fish, making them vulnerable to predators and leaving them unable to locate prey or mates or communicate with each other.
Oil Spills - Obviously, offshore drilling also increases the risks of oil spill from drilling itself or from the transportation of the oil from the rig. As we have learned from the Deepwater Horizon, the Exxon Valdez, or simply after hurricanes pass through the Gulf of Mexico, thousands of animals die as a result of these oil spills. In the long-run, an oiled and degraded habitat reduces productivity, affects the health and immune system of marine animals, disturbs the food chain, and reduces the chances of development in fish eggs and larvae. It is also extremely costly for the fishing and tourism industries for the coastal communities that rely heavily on them.
Recovery from an oil spill takes years. In 2014, NOAA published this graphic showing the recovery timeline for different species after the 1989 Exxon Valdez spill. As indicated, 25 years later, some species are still in the process of recovering, and some have not shown any signs of recovery at all.
Toxic waste pollution - In addition to environmental damage from oil spills, the routine operations associated with offshore drilling produce many toxic wastes and other forms of pollution. Each oil platform can discharge hundreds of thousands of gallons of contaminated water daily, affecting both local waters and those down current from the discharge.
Policy-makers need to remember that our oceans create over half of our oxygen, drive our weather systems, govern the flow of nutrient and energy around the world, and provide us with vital sources of protein, energy, minerals and other products. In the face of the climate crisis, every nation need to look for ways to decrease petroleum consumption, not for ways to increase it.