Oil spill damage not related to size

I’VE just read that in the US, Hurricane Alex has pushed a huge oil slick towards Grand Isle on the Louisiana coast, already in imminent danger of inundation from BP’s Deepwater Horizon which is pumping between 50,000 and 100,000 barrels of oil a day into the sea.

It has, so far, discharged two million barrels.

I received pictures of Grand Isle last week from an old friend of mine, the American writer, Peter Nichols. He ironically calls the photos ‘Holiday Snaps’. They show a coastal field marked with crosses like those in the cemeteries of The Somme. Each simple, white wooden cross is marked with the name of a species of flora or fauna, or of a human livelihood or tradition damaged or lost forever as a result of the oil.

The crosses were erected by locals mourning the erosion, and in some cases, the extinction, of a way of life. The crab bakes, redfish rodeos and shrimping that the Bayou people celebrated will be no more. The slick currently covers 4,000 sq miles of ocean. I remembered a song that went:

Shrimp boats is a-comin’/Their sails are in sight/Shrimp boats is a-comin’/There’s dancin’ tonight.

I looked up the lyrics and found a verse that says:

They go to sea with the evenin’ tides/And their women folk wave their good-byes/While the Louisiana moon floats on high/ And they wait for the day that they can cry....Shrimp boats is a-comin’/There’s dancin’ tonight!

I fear that there will be no shrimp boats a-comin’ for a long time and the crying will be for sadness not for joy.

Yet, amazingly, this spill doesn’t even figure in the list of the 50 largest spills worldwide. However, size doesn’t always matter where oil spill destruction is measured.

The June 12 issue of New Scientist points out that while, in 1979, a well off Mexico’s Gulf Coast spewed 530 million litres of light crude oil – three times current estimates for Deepwater Horizon – into warm, shallow waters washing onto sandy shores, five years later a UN monitoring team “had to look hard to find any lasting effects”.

However, in Louisiana, the coastline is salt water marshes, which a coating of the heavy crude oil coming from the well will destroy. Heavy crude from the Exxon Valdez disaster in 1989 is still negatively affecting the Alaskan coast, yet the amount, 40m litres, was paltry compared with the 2m barrels (318m litres) already spewed out by Deepwater Horizon.

The sludge of crude covering the Louisiana seabed will be attacked by bacteria: the bacteria in the Gulf, accustomed to oil leakage, have evolved as efficient oil feeders. But it will take decades before the seabed flora and fauna will return. The many specialised habitat ‘zones’ between it and the surface are also devastated. The oil plume, rising from 1.5km below, disperses at every level. The free-swimming species will also take years to recover.

The Deepwater Horizon well is at the end of one branch of the Gulf Stream and it is possible that the oil may spread into the Atlantic Ocean. If it were to reach Irish beaches, it would likely be in congealed lumps, known as tar balls. These are unsightly, but not seriously destructive. As children at the seaside, when we accidentally stood on tar, our mothers resorted to butter from the picnic hamper to dissolve it. By the time I had my own children, we generally had sun cream.

Fuel oil emissions have always endangered the environment but now, as the Deepwater Horizon crisis proves, harvesting the remaining stocks of oil is becoming increasingly hazardous.

I read in my son’s Leeds Metropolitan University alumni magazine that the university’s Professor Greg Keeffe has come up with an eco-friendly alternative to oil for powering post-industrial cities. Algaes, grown in massive glass tanks in urban wastelands would, he explains, “offer energy yields over 100 times greater than bio-crops such as rapeseed, and [do] not compete for arable land.” With rapeseed, 900,000 hectares – all the arable land in Lancashire – would be required to power Liverpool.

Cultivated algaes can, apparently, produce 150,000 litres of biofuel per hectare per year; one hectare alone produces enough for a family car to circumscribe the globe 75 times. Simultaneously, these urban algae reactors would act as colossal carbon sinks. Has Professor Keeffe got something there?