Not megasquaremetres! The prefix attaches to the unit and both are squared (or cubed for volume) Either square megameters, or megameters squared, both describing an area 1000 km x 1000 km.
After 999 dam³ comes 1 hm³, but the SAE doesn't build dams and this exceeds what a farmer is likely to use for irrigation, at least a single application. Besides Light Vehicle, SAE has groups for Heavy Truck & Coach, Offroad (which includes ag and stationary equipment as well as giant mining equipment), and an Aircraft group. We are not the primary professional society for aircraft and I know nothing about that group other than its existence. There may also be a group for Rail; if so, again "I know nothing." Actually, rail must fall somewhere, as it is covered in SAE Metric Practice. Your water supply capacity would be 21.5 hm³, and I would suggest that this gives a sense of scale not easily imagined from 21.5 GL; however, the two are equivalent. ________________________________ From: Pat Naughtin <[email protected]> To: U.S. Metric Association <[email protected]> Sent: Thu, June 10, 2010 10:16:55 PM Subject: [USMA:47677] Re: Oil Spill Technical Team Using SI Dear John and Paul, I have interspersed two thoughts. On 2010/06/11, at 02:23 , John M. Steele wrote: > >I can envision 1 L or a few, I can't envision 3 million. Would not 3000 m³ be >a lot better than throwing in "big counting words" in lieu of a suitable unit >or prefix? One problem with this is that we tend to avoid using prefixes with SI units like cubic metres; megasquaremetres doesn't work linguistically. An alternative we use widely in Australia is to add prefixes to the SI unit litre. I will probably take flack for this one, but SAE metric practice is to use the cubic dekameter for large amounts of water, such as irrigation, where traditional measure would be the acre-foot. In that notation, the leak would be 3 dam³/day. Irrigation water in Australia is measured in litres. To avoid the issues of false precision and uncomfortable prefix use (such as megacubicdecametres) our practice here is to use litres for kitchen use, kilolitres for household rainwater tanks, megalitres for farm irrigation or small dam storage, and gigalitres for large dam storage amounts. Our water supply for Geelong has a capacity of 21 504 megalitres and it currently (after 12 years of drought) contains 4724 megalitres. If as Paul reports (below) a figure for the oil Gulf oil flow is '3 million litres per day' we would more likely use '3 megalitres per day' in Australia. Cheers, Pat Naughtin Author of the ebook, Metrication Leaders Guide, see http://metricationmatters.com/MetricationLeadersGuideInfo.html Hear Pat speak at: http://www.youtube.com/watch?v=_lshRAPvPZY PO Box 305 Belmont 3216, Geelong, Australia Phone: 61 3 5241 2008 Metric system consultant, writer, and speaker, Pat Naughtin, has helped thousands of people and hundreds of companies upgrade to the modern metric system smoothly, quickly, and so economically that they now save thousands each year when buying, processing, or selling for their businesses. Pat provides services and resources for many different trades, crafts, and professions for commercial, industrial and government metrication leaders in Asia, Europe, and in the USA. Pat's clients include the Australian Government, Google, NASA, NIST, and the metric associations of Canada, the UK, and the USA. See http://www.metricationmatters.com/ to subscribe. > > ________________________________ From: Paul Armstrong <[email protected]> >To: U.S. Metric Association <[email protected]> >Sent: Thu, June 10, 2010 11:48:40 AM >Subject: [USMA:47645] Re: Oil Spill Technical Team Using SI > > >At 2010-06-09T14:20-0500, [email protected] wrote: >> I *heard* on a news network that the Technical Team assigned to >> measure the flow rate of crude oil and gas leaking from the floor of >> the Gulf of Mexico is measuring depth in meters, *independent* of BP >> statements. >> >> What unit of flow rate is being used by the Team? I would like to >> hear the rate in kg/s for each major hydrocarbon component of the >> liquid and gas leakage. >> >> Neither "barrels per day" nor "gallons per day" is acceptable. > >The last time I heard a story about it was a BBC world service podcast >where "3 million liters per day" was used. > >Paul > >
