The Resilience of The Gulf: Oil Seeps and Oil Spills Haven't and Won't Kill the Gulf Of Mexico
BP is bad – bad, bad, bad, bad, really, awfully, deeply bad. I would call them naughty as well, but they’re British and they might actually enjoy that.
I say all this up front so that no one will think that anything I say in the rest of this article is a defense of BP, which is bad. If we can just put aside the badness of BP for a moment, though, it might allow us to ask a few questions that somehow went unaddressed throughout the 90-day live broadcast of the Gulf Oil Spill and Spectacle, such as: how bad was the spill? Is there any precedent to judge its impact on that region of the Gulf? How long might it take the area to recover biologically? Will there be irreparable long-term consequences?
In short, was the spill really Armageddon for all life in, above, below and near the Gulf of Mexico – an alien shock far beyond the coping capacity of the fragile web of life, as advertised?
As it turns out, there is a relevant precedent that can shed light on these questions about the massive oil spill of 2010: the massive oil spill of 2009, and 2008, and 2007, and…
Having spent a big part of my life in Houston, and therefore having spent a few weekends in Galveston, I can attest that the Gulf of Mexico has seen a few tar balls. In fact, the Indians collected them from the beaches of the Gulf as a raw material long before BP followed Columbus across the Atlantic and began drilling holes in the ground without much of a back-up plan. The Indians were able to do so because oil is a natural substance that constantly seeps up through fissures from subterranean reservoirs, both on dry land and under the sea.
This is why we have accounts of oil and asphalt being used as far back as the Babylonians, why Noah was able to coat his ark in pitch and also why sabre-toothed tigers were able to get stuck in the La Brea Tar Pits without any help from BP or even the Exxon Valdez.
When oil seeps through fissures in the seabed, the result is a natural oil slick on the surface of the water – an event that is remarkably common in-oil bearing regions such as the northern Gulf of Mexico, as evidenced by satellite imagery and local observation. A survey in 1996 documented 63 natural oil seep sites occurring in an offshore band running from a point well south of Galveston to a point similarly south of the Alabama coast. The extent of these seeps would likely surprise most people, since, for some reason, they garner no media attention.
A 2003 research paper by Kvenvolden and Cooper in Geo-Marine Letters estimated that natural seeps dump 140,000 metric tons of crude oil into the Gulf of Mexico each year -over one million barrels of crude per year. In fact, the authors estimate that 47% of all the petroleum found in the sea is from natural seeps – the largest single source, ahead of airborne pollution, ground runoff and drilling/shipping accidents.
The Deepwater Horizon blowout has been estimated (at the high end) at 2,000,000 to 3,000,000 barrels of unrecovered oil, total. This is clearly a legally and technically unacceptable amount, but it is of a similar order of magnitude to the amount of oil the Gulf digests in its “pure” state in a year with no (man-made) oil spills at all. The BP debacle triples the natural background oil in the Gulf. It seems probable (to me, at least) that the Gulf can deal with this, given a relatively short amount of time to do so.
This is especially true when one considers that the main mechanism for the removal of oil, whether it leaks from natural holes or the holes at BP, is simple evaporation. This is why the light, sweet crude of the Gulf can be spilled in million-barrel quantities every year and result in only a relatively small quantity of thick tar balls washing ashore. Evaporation is, for the scale being discussed here, a “non-saturable” mechanism. So a tripling of oil on the surface should result in a tripling of the rate of oil removal by evaporation. This is one advantage of oil floating and spreading out in a sheen less than a micron thick at the surface of the water: this creates a lot of surface area for the wind and sun to work on. (The other advantage is that, at less than a micron thick, even a small spill can cover huge swaths of water and be described by the media in excited terms such as an oil spill “bigger than Tennessee.”)
The remainder of the natural oil not evaporated each year is broken down by oil-eating bacteria (which did not instantly evolve in the hours following the Deepwater Horizon explosion – more proof that oil is constantly entering the seas) or it is buried in sediments along with other hydrocarbon-rich detritus – both equally scalable processes.
This is not to say that the oil spill didn’t happen or has had no effects – clearly it has. The amount of oil released was large and it was released in just three months at one location. But the petroleum Tsunami gleefully anticipated by the cable crisis channels did not occur. Neither did biblical-scale die-offs of wildlife. Damage has been very localized and recovery has already been faster than anticipated. Keep in mind that the best estimates are that an oil slick has a half-life of around12 hours before dispersal and evaporation destroy it as a coherent entity. Within days of the plugging of the BP well, oil was so difficult for news crews to find that they moved on to stories about Lindsay Lohan’s courtroom nail polish.
We may even have to consider the possibility that, economically, the excited response to the spill did more damage to the region than the actual effects of the spill itself.
BP is bad. But it will take a lot more than leaked oil on this scale to kill the Gulf. It’s been dealing with a million barrels of oil per year since long before Mankind arrived to drill ill-planned holes in the crust around the natural seeps he found. I point this out, not as a defense of BP or an apology for oil, but because it is true and at some point, truth should enter into the discussion – before the EPA declares the Gulf a superfund site and bans shrimp for the next 42 years.
Oil, despite every description to the contrary, is natural product, and nature has ways of dealing with it.