I was reading this article and came upon a perplexing quote:
I don’t know what’s up with those guys at Woods Hole not releasing rates quantifiable in ‘actual amounts’. Still, sometimes I waste time asking stupid questions (kind of like a hobby), and today I wonder how many gallons there are in a cubic meter.
Also, if you want to do any kind of unit conversions, Google will do that for you. Just type in “1 cubic meter in US gallons” (or any other amount or units.) For example, “1.26 million gallons in cubic meters” will give you the answer: “1.26 million US gallons = 4 769.61885 cubic meters.”
What do you mean by “actual amount”? I see the quote you’ve posted, but I have no idea what the article means by “actual amount” in that context. 264 gallons is 1 cubic meter. I don’t see what’s not “actual” about that.
Yes, gallons in a cubic meter is a perfectly defined number.
The uncertainty comes in when the DOI (or whoever) tries to convert a rough estimate (Uh…maybe a m^3/s?) into a different unit (uh…maybe 1.05 to 1.26 gal a day?)
At the risk of sounding overly pedantic, there are three different gallons and the Google calculater seems to silently assume you want U.S. liquid gallons.
Since this is British Petroleum one wonders if they make quantities seem smaller by quoting in Imperial gallons which are 20% larger than U.S. liquid gallons.
Finally, one may sometimes encounter the U.S. dry gallon, 1/8 of a bushel (though the U.S. bushel is slightly smaller tha an Imperial bushel).
For Imperial gallons you can get a good estimate in your head:
One cubic metre of fresh water = 1 tonne
One tonne = 1 Imperial ton (approx) = 2240 lb
One Imperial gallon of fresh water = 10 lb (definition)
==> one cubic metre = 224 gallons approx.
If you want to get closer you can even start looking things up.
The article is not saying the oil is gushing out at a rate of one cubic meter per second. It’s saying that the release by the Department of the Interior gave a rate expressed in cubic meters per second, whose amount apparently converts to 1.05 million - 1.26 million US gallons per day.
So, this amount is a rate, not an actual amount. It’s telling you how much and how fast the oil is gushing out, but not giving you an actual number of how much oil over time has gushed out. You need to figure out how long it’s been gushing out at that rate to find out the actual amount of oil spilled.
Yes, converting from cubic meters/second to gallons per day is an excellent 6th grade math problem. Apparently none of those reporters passed 6th grade math, or have 6th graders at home. Of course, the article also has ridiculous but beloved journalistic comparisons like:
What if you put the oil in juice boxes, and laid them end to end? Then they would reach almost 1/3 of the way to the moon!
The actual amount per day also depends on the actual rate. If the oil is coming out at a constant rate, then this is a simple unit conversion. However, if the oil isn’t coming out at a constant cubic meter per second, but actually at a varying rate whose variation is difficult or impossible to determine, this also complicates calculating the ‘actual’ amount of oil coming out per day.
That converts to a range of 2,738,935.84 US gallons per day to 5,249,627.02 US gallons per day. So I’m still not sure where the 1.05 million to 1.26 million number comes from. It does also say:
So perhaps there’s an adjustment downward to account for this, but I can’t find any solid numbers, just this statement in Woods Hole PDF link on that web page:
So, I have no idea where those numbers are coming from.