The Science of Oil Spills

By Cameron Carlson

From all the way out in Anchorage, Alaska, I’m Cameron Carlson and I had the amazing opportunity of joining the Bigelow summer REU. I am a biochemistry major from the University of Alaska Anchorage, where I primarily research the science of oil spills.

Oceanography is a deeply important topic in a state surrounded by ocean on three sides, though frankly, I joined up with Bigelow to learn more about analytical chemistry. The project at Bigelow I was interested in is studying compounds that I study in Alaska, but with different instruments. The absolute master course on ocean sciences I have received on top of that has been a welcome surprise. The internship taught me to appreciate the project more holistically, contextualizing the research in the realm of ocean studies.

As for the project itself, I am assisting in researching the effects of petroleum spills on copepods, a nutrient-rich zooplankton. Contemporary studies make clear the toxicity of oil to copepods, which is exacerbated by the go-to remediation technique, application of oil dispersant. But, most studies are conducted in small systems which may not be representative of the ocean environment. These systems, which fail to account for the scale and depth of the ocean, consequently do not account for a simple response for zooplankton when subjected to oil: to swim away. Copepods regularly dive over 100 meters over the course of a day to avoid predators, so why wouldn’t they do the same to avoid toxic oil hydrocarbons?

Why do we care if plankton can dive away from dispersed oil? Marine oil spills are inevitable: barring the current world-shaking crisis which has gas prices at record lows, oil exploration does not show signs of slowing down. This is especially true in Alaska. Despite the state’s haunted legacy of petroleum environmental disasters like the Exxon-Valdez spill, several lease sales for oil and natural gas extraction are planned for the Beaufort Sea. Chemical dispersants are, generally speaking, the popular remediation method when oil is spilled in the ocean, because it breaks the oil into small droplets, which microbes can degrade much faster.

However, if copepods are exposed to oil more due to dispersants, they can carry these toxins into the food chain when they are eaten by small fish, which are then eaten by bigger fish, birds, marine mammals, and humans. The research question posed at Bigelow is, is this consideration necessary? If copepods can simply dive away from dispersed oil and avoid it just as effectively as undispersed oil, then organizations such as the US Coast Guard don’t need to even worry about these animals when deciding how an oil spill is treated.

This question is being tested at Bigelow by observing copepods in systems which provide vertical space to move in – basically very tall aquaria. Oil or dispersed oil is introduced to the top of these tanks, then the copepods’ vertical distribution over time is recorded with cameras. My slice of the project is seeing the chemical constituencies of the water at varying depths over time, ensuring copepods are actually moving to areas of lower toxic hydrocarbon concentration. This has worked out surprisingly well from over 3000 miles away. I’m not operating the instruments, but I get all of the outputs, then develop it into meaningful data.

The idea of a distance internship had me extremely nervous, and not just because of the four-hour time difference which has me waking up at the crack of dawn. I found out that the pain caused by a radical change scales with my resistance to the situation. I learned a lot about keeping an open mind with Bigelow.

Cameron Carlson is a University of Alaska Anchorage student in Bigelow Laboratory for Ocean Science’s Research Experience for Undergraduates program. This intensive experience provides an immersion in ocean research with an emphasis on state-of-the-art methods and technologies.

The Science of Oil Spills