Keeping Up with the Oil Spill

Listen to Cutler Cleveland, a CAS professor of geography and environment, discuss the ecological damage caused by BP’s Deepwater Horizon oil spill. Watch more here.

It’s Day 52. Despite a recent prediction from BP that the flow of oil into the Gulf of Mexico will soon be reduced to a trickle (one executive even pegged the end as precisely as next week), no one knows for sure when it’s going to stop or even how much crude is spewing each day or what the final, disastrous tally will look like. But online, Cutler Cleveland is painting as precise a picture as can be found these days. The College of Arts & Sciences professor of geography and environment and editor of the Encyclopedia of Earth, a Wikipedia-like ecological resource with strict quality control, has seen the entry on the BP oil spill grow almost as quickly as the slick itself. From undersea plumes and natural oil seeps to cleanup efforts and analysis of rhetoric from the government as compared to from BP, Cleveland and his contributors have created a reliable go-to information source for the media and the public on what is now considered the worst environmental disaster in U.S. history.

BU Today talked with Cleveland about the spill and its coverage.

BU Today: How often do you update the entry on the BP oil spill?
Cleveland: A couple of times a day. Right now, I’m working on the confusion over the drilling moratorium. On the 27th, Obama publicly rescinded his proposal for exploratory drilling offshore and a couple of days later Secretary of the Interior Ken Salazar issued a memorandum to the Minerals Management Service (MMS) and told them not to process any new applications for drilling permits for so-called deep wells. Then there was a lot of confusion within MMS about what “deep” really meant. Last Wednesday, they actually issued a couple of permits for shallow wells off the coast of Louisiana and Mississippi. The next day, they rescinded those permits. It looks like they will allow for some shallow water drilling after some review, but for the time being, deep-water drilling is off limits.

There are said to be naturally occurring oil seeps in the Gulf. How does their output compare to the BP leak?
We know from remote sensing and satellite imagery that there are a lot of natural seeps in the Gulf of Mexico. It’s quite an active area, but these seeps are spread over the entire Gulf of Mexico and occur rather slowly. A couple of the biggest oil seeps in the world have been studied in great detail, including one off the coast of California that seeps about 100 barrels a day. The Deepwater Horizon leak is releasing 12,000 to 19,000 a day. That’s 3 to 12 times the amount of oil per day compared to all the seeps across the entire Gulf of Mexico.

Does that mean that sea life has a certain immunity to oil toxicity?
In a limited sense. There’s a substantial microbial community in the Gulf of Mexico water column that degrades oil. The existence of these microbes is probably due in part to the existence of these oil seeps. Presumably, some or a lot of the oil being released by the Deepwater Horizon is being degraded by these natural processes. The rate of such a sudden, concentrated, and massive event is certainly overwhelming to most natural mechanisms for oil dispersal and breakdown.

Some have painted ecological doomsday scenarios for the Gulf of Mexico. Could all this oil actually render the gulf no longer viable?
I doubt it. The amount of oil that’s in that field is in the order of tens of millions of barrels. If the leak completely drained this reservoir, and I’m not even sure a single well could do that, that would be a huge of amount of oil, but the Gulf of Mexico is a very large body of water. While that amount of oil would cause large-scale ecological harm, it seems a bit far-fetched that it would actually kill off the entire Gulf of Mexico.

What ecological impacts from the 1989 Exxon Valdez spill are we still dealing with?
What we know from the Exxon spill is that the ecosystem does recover, eventually. But we also know that there are some fairly long-lasting impacts. A number of the fisheries and bird populations that were impacted took several generations to recover. If you go to the shoreline of many of those areas and dig down with a shovel a foot or so and watch the water fill in, you’ll see oil on top of it. There’s oil still down in the sediment and in extreme weather, some of the oil can be reworked and reintroduced into the water column, where it can potentially have impact.

What does the public need to understand about the ramifications of this current spill?
The importance of wetlands. The environment supports human life in a lot of ways. We tend to think about that in terms of what we extract: wood, water, oil, coals, metals, fish. There’s also this vast array of ecosystem services that support human life: the provision of fresh water, nutrient cycling, a stable climate, pest control, pollination. Wetlands, per acre, are among the most important ecosystems on the planet. Louisiana has among the largest concentration of coastal wetlands in the world that support, among other things, one of the most productive fisheries in the world.

The Louisiana wetlands had been under siege by humans even before the oil spill. The oil companies have had their way in Louisiana for more than half a century in terms of exploring for oil and gas under the wetlands and in the coastal waters. A lot of the wetlands have been lost, converted to open water due to canals and other activity by the oil and gas companies and human activity in general. So this spill just adds insult to injury in terms of the loss of their importance.

And once wetlands are converted to open water, are they lost for good?
For all intents and purposes. In south Louisiana, the Mississippi River brings tons of sediment. When it floods, it deposits this sediment and plants establish themselves. Over time, the Mississippi has built up land and eroded it in other places. But since humans started to levee the Mississippi to prevent flooding, and dredged canals, the wetlands were converted to open water. Without input of sediment, the marshes disappear. A lot of the disappearance is from the oil and gas industry. The state of Louisiana never met a drilling permit it didn’t like. It’s only as people have started to understand how important wetlands are ecologically and biologically that the state has started to wise up. But there’s a long way to go.

Caleb Daniloff can be reached at cdanilof@bu.edu.