How big is that oil spill?

A reader of Metric Views points out that confusion on the reporting of this disaster is not limited to the UK.

Eric writes:

“Fully metricated Australia seems to lose its metric bearing completely when it comes to news about the tragic oil spill in America. All media outlets except newspapers, who at least convert outdated medieval measurements, use a mixture of both. From 2000 up to 5000 feet, down to barrels and gallons, with litres thrown in, are often used without conversions. The irony is that only older people know what a gallon is and probably nobody knows how many litres a barrel holds? I did write to two TV stations pointing out that needless retro step, but have as yet received only an acknowledgement. It sure would help if a few more Australians take the time to object to this irritating anomaly.”

Are more of our readers being confused by reports which use a mix of US customary, Imperial and metric measures?

(Note: one barrel of oil is about 159 litres or 42 US gallons or 35 Imperial gallons)

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8 Responses to How big is that oil spill?

  1. Matt says:

    I'd assumed a barrel of oil was roughly 200L, roughly the capacity of a normal chemical drum (the standard blue metal ones).

    Does anyone use barrel-of-oil-sized containers any more?


  2. John Steele says:

    I'm a little surprised at the confusion in Australia. However, this story
    describes the same box (which failed) as 100 tonnes in the text and 90 tonnes in the photo. 🙂

    It has been described in the US press as 100 (presumably short) tons so about 91 t. There is probably no serious error in rounding to 90 t as I doubt it was weighed that carefully.

    The leak was originally described as 1000 barrels per day, later increased to 5000. With luck, the five might be a significant digit. Both are SWAGS of no great precision. However they are barrels of 42 US gallons (definition), about 159 L or about 35 Imp. gallons. How about 800 m³/day for metric countries.

    The UK likes to cling to Imperial and pretend it has a measurment system in common with the US, but long and short tons, and Imperial and US gallons are certainly areas where the two differ. The easiest way to explain these differences is simply to convert to metric and be done with it.

  3. David Brown says:

    Yes, this has been very confusing in the UK. I think that the press releases coming out of the US are to blame, as are the news agencies like the BBC who don't have a policy on reporting of units. The figure 5 000 barrels (210 000 gallons) has been widely reported in the UK without any explaination that these gallons are US gallons which are different from the ones that used to be used in the UK. I even saw a respected publication translate the 210 000 gallons as 954 700 litres, mistaking them for imperial gallons before doing the conversion (in fact 210 000 US gallons is 794 900 litres). Similarly the sea depth of 5 000 feet has converted sometimes to 1 mile and sometimes to 1 500 m. One recent report had it as "almost a mile (1.6 km)"
    If news agencies had a policy to convert everything to a single system of measurement before reporting, and that system was metric, then there would be less of a problem. Metrication of the oil industry would clearly be a far better solution, but since the USA is such a big player in that industry we may have to wait a little before that occurs.

  4. Alex Bailey says:

    I'd guess that this is as much to do with the influence of US media as anything else, newspapers will likely have time to do the conversions whereas TV news outlets will want to get the story out before their competitors... add the fact that foreign correspondents under pressure will likely just parrot local sources and, probably living in that part of the world, will probably have "gone native" to some extent.

    I think this once more highlights the fact that the USA continues to be the factor that holds the rest of the English speaking world back.

  5. Seares says:

    As I've said elsewhere, it doesn't matter what units are used, as no-one can visualise what it means, apart from it must be a huge amount of oil. whether in gallons, litres, or standard buckets. I suggested using "n times the area of Wales" for area (UK readers), but as John Steele says: "... they are barrels of 42 US gallons (definition), about 159 L or about 35 Imp. gallons. How about 800 m³/day for metric countries." Well, my domestic water useage is about 50m³ per month, so the oil pouring out daily on that calculation must be equivalent to about 500 times what I use per day... doesn't seem much. Which just shows the futility of these arguments. Now, if it's miles v. km, that's something worth going on about!

  6. Ezra Steinberg says:

    Given all this confusion, one might at least hope that the new government in Westminster will see the light and decide that leaving Britain mired in the metric muddle is sheer measurement mayhem.

    If that turns out to be the case, perhaps they will prevail upon at least the BBC (including its local outlets) to adopt an editorial policy of "metric only" for units. This would hopefully lead the way for other media outlets (both print and electronic) to adopt similar policies.

    In the case of television reporting from the USA whose video clips are rebroadcast "as is" to quickly relay up-to-the-minute coverage, the BBC could easily add a chyron (lower third) at the bottom of the screen with drop-shadowed text that converts the US Customary units used in the clip's audio track to metric.

  7. michael says:

    'perhaps they will prevail upon at least the BBC (including its local outlets) to adopt an editorial policy of “metric only” for units'

    I have emailed the BBC on this very issue several times via their complaints link. I feel strongly as the National broadcaster that they should consistently adopt metric units only in any factual reporting.

    The BBC does seem to be getting better - this morning they revealed that eating as little as 50g of processed meat a day was bad for you. They didn't even convert this amount into ounces! And they also seem to be using metres more when indicating sizes of objects and short distances.

    As far as international stories go, I too have observed that they tend to report it in the 'local' units of the story that they are covering. This is a shame - in other European countries I have noticed that if I am watching a program recorded in English but that has native subtitles, these always convert any imperial measurements into metric terms. Eg while watching an episode of CSI in Sweden, the subtitles referred to the '6 foot suspect' as 1.83m.

  8. John Steele says:

    Well, the leak has "grown" from 1000 barrels per day, to 5000, to a range of 12000 - 19000, and even that seems to be in dispute. I thought I understand precision, significance, and rounding, but I admit I don't know how to properly convert a number with no significant figures and a debatable order of magnitude.

    The source of all the estimates (in barrels) appears to be BP, from coverage here. That prompts the question why is BRITISH Petroleum measuring (guessing at?) the leak in AMERICAN barrels. I'm not sure if they think that helps or hinders understanding.

    Measuring the leak is tough. You can't measure all the oil or get a flow meter down there. The video shows substantial velocity shift across the pipe end (very fast near the gas jet, slow opposite). In theory, cross section area times average velocity should give the flow, but estimating average velocity from the video looks tough.


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