An inch of rain?

[Roger Chapman]

You might have but with me being an offcumden I have my weather station set to inches. ISTR that in one particularly memorable cloudburst I recorded an inch of rain in about 15 minutes.

[Skipweasel]

Dave, is that actually you, or someone masquerading as you being dim?

[Skipweasel]

Now I know it's not you.

[The Medway Handyman]

No - it really is me being dim :-)

.... and I still don't understand!

[The Medway Handyman]

I can see why volume is meaningless, but surely depth has too be related to area?

>

[Skipweasel]

If the forecaster says "An inch of rain fell in Shropshire today"[1] then he means that the whole of Shropshire is covered to a depth of an inch - or it would be if it didn't trickle away.

Your bucket would have an inch in it, the ant standing on the rim would have an inch balanced on its head and the car park would have an inch of rain on it.

[Skipweasel]

Yes. That's why they specify an area. "England" or "In the Wet Mudlands [1]" or "On the hills above Bideford."

[1] And boy can they get muddy.

[The Medway Handyman]

Mr Wadsworth has explained things off group. 'Bing'

I admit to being dim :-)

[Skipweasel]

[1] As it often does - not for nothing is it called Slopshire.

[Andy Burns]

Which is heavier, a pound of feathers or a pound of lead?

[Ron Lowe]

Think of it this way:

Consider the rain 'density'. The rain is coming down at a certain volume per Sq. M of exposed surface area. Let's call it X cc per Sq.M per hour.

So 1 Square meter will accumulate X cc in 1 hour. This will fill it to Y cm ( do the math yourself: 1 Cu. M = 1000000cc )

But 2 square meters will accumulate 2X cc in 1 hour. This will also fill to Y cm, because although we've captured twice the volume, it's spread over twice the area.

Get it?

The increased surface area will fill to the same depth, because the capture area has increased along with the area to be filled. They cancel out.

[Bob Eager]

Think about it. Bucket and pool. They will both fill to the same depth. You may say "but the pool will spread the water out more thinly". But...the pool is catching more water because its area is greater.

[The Medway Handyman]

You be Salopian then?

[Skipweasel]

By house-purchase, not birth. I grew up in Kemsing and Otford.

[djc]

Well, to be strictly accurate the weather station somewhere in Shropshire recorded an inch at that spot and it is assumed that it was much the same all over county.

[brass monkey]

Is it the blue whale?

[Skipweasel]

Backed up by the rainfall radar, these days.

[John Rumm]

The lead obviously....

by a very small amount ;-)

[Ronald Raygun]

No, it's the feathers, because you can handle (and weigh) a pound of lead just as it is, but the pound of feathers will need a sack around them, and that will add a few ounces to the weight.

[Ronald Raygun]

Trust you to build up to a joke and forget to include the punchline.