Should one expect a slightly better grasp of basic arithmetic from NASA?

http://www.jpl.nasa.gov/news/news.cfm?release=2012-036#4

The total global ice mass lost from Greenland, Antarctica and Earth's glaciers and ice caps during the study period was about 4.3 trillion tons (1,000 cubic miles), adding about 0.5 inches (12 millimeters) to global sea level. That's enough ice to cover the United States 1.5 feet (0.5 meters) deep.

Right, firstly I'm ignoring whether the numbers are correct and whether 12mm of sea level rise equates to 0.5m over the area of the USA, although it's a nice, emotive example to use and in no way could it be considered scaremongering. My issue is the basic arithmetic involved:

Half an inch is 13mm not 12mm if we're rounding to the nearest mm. However, I'll give the benefit of the doubt and assume that they said "about" half an inch to help the pre-decimal amongst us understand 12mm.

500mm is in no way 1.5 feet, 500mm is a little over 19 and a half inches, which, if you must decimalise it is a little under 1.63 inches.

Yes, this is a bit picky, but if they can't even consistently convert between metric and imperial units then why would I trust their ability to handle the higher level mathematics involved in the actual study?

I see this as simple journalistic licence in that giving figures to decimal precision takes away from the general topic of conversation. It's the reverse of the BBCs continual conversion of sums in US $ to UK £ i.e. "he was awarded $100m (£67m) in damages" (when by your argument they really should say £66,345,288....... )

Not to be picky but....

Shouldn't it be 1.63 feet and not 1.63 inches?

:)

Very good Terry :-)

Dave, no, not quite what i was trying to get at.
I think it's more that 1.5 feet implies a far greater degree of precision than about a foot and a half. If they're going to imply that level of precision then they should be accurate to at least as many significant figures.

Like I said, it is picky.

There is an anthropogenic crater on Mars named after one of those basic metric/imperial errors.

SteveW -
I agree that the NASA sentence about the equivalent depth of ice over the US couldn't possibly be considered to be scaremongering. But can you imagine if it were a British agency producing that press release? The melt over 8 years would be equated to about 60 feet of ice over all of Great Britain! [Again, not to be scaremongering.]

So half an inch of extra sea level

How much coastal land mass have they lost then

So half an inch of extra sea level

How much coastal land mass have they lost then