Lies, damn lies, and oil spill statistics
Justin Gillis has a great story about how no one with the ability to do anything about it seems remotely interested in measuring the severity of the oil spill in the Gulf of Mexico. The ubiquitous 5,000-barrels-a-day number seems to be a massive underestimate, and the stated reason for not getting a better figure is weak indeed:
A spokesman, David H. Nicholas, said in an e-mail message that “the estimated rate of flow would not affect either the direction or scale of our response, which is the largest in history.” …
“I think the estimate at the time was, and remains, a reasonable estimate,” said Dr. Lubchenco, the NOAA administrator. “Having greater precision about the flow rate would not really help in any way. We would be doing the same things.”
Why is the NOAA backing BP up on this? Knowing the size of the problem may or may not help in terms of being able to fix this particular problem. But it’s certainly going to be important going forwards.
What’s more, the current estimate could hardly have been friendlier towards BP if it had tried:
The 5,000-barrel-a-day estimate was produced in Seattle by a NOAA unit that responds to oil spills. It was calculated with a protocol known as the Bonn convention that calls for measuring the extent of an oil spill, using its color to judge the thickness of oil atop the water, and then multiplying.
However, Alun Lewis, a British oil-spill consultant who is an authority on the Bonn convention, said the method was specifically not recommended for analyzing large spills like the one in the Gulf of Mexico, since the thickness was too difficult to judge in such a case.
Even when used for smaller spills, he said, correct application of the technique would never produce a single point estimate, like the government’s figure of 5,000 barrels a day, but rather a range that would likely be quite wide.
Why release a point estimate? Well, if the NOAA had released a range — say 3,000 to 30,000 barrels a day — then the press would have gravitated to the higher number, and talked about a spill of “as much as 30,000 barrels a day”, and that would be the main number people remembered. But it’s not the NOAA’s job to do PR for BP. And it is the NOAA’s job to get as much good information about this oil spill as possible.
So let’s get down there and measure this thing.