Units moderator. There should be a units moderator assigned.

[wattmatters]

But I find it amusing that you can average out a more or less random and confused twenty foot ocean swell to +/- 1mm of accuracy.

With sufficient data it's definitely possible. The signal:noise would be high with an ocean of data.

Tide stations avoid much of the ocean swell issues and have water calming measures.

 

[OffGridForGood]

I guess you could use a really big floating chunk of ice like 600,000 sq km as a water calming feature and measure the elevation of the Ross Ice Shelf - ya said you worked in Antarctica !

 

[Hedges]

Do you measure the water level relative to the top of the floating ice?

As ice melts, your frame of reference moves.
Melting both from the top and bottom.

 

[Warpspeed]

Actually, at sub zero temperatures ice and snow ablate, its a kind of erosion.
The wind carries away microscopic ice crystals, and the ice/snow just disappears without actual melting.

 

[wattmatters]

Do you measure the water level relative to the top of the floating ice?

Presumably from the edge of the continent like most tidal stations. These are the ones in Antarctica:

SCAR GSSG - GIANT Permanent Tide Gauge Observatory Sites

 

[upnorthandpersonal]

3.14 is close enough for non technical stuff. Most people can remember that.

And in some cases like astronomy when all you need is a broad order of magnitude, you make Pi = 1

 

[wattmatters]

And in some cases like astronomy when all you need is a broad order of magnitude, you make Pi = 1

That's like turning parsecs into lightyears.

 

[McKravitts]

3.14159265357 is about all I remember. Apparently I'm a couple digit's short of NASA's requirements, and my brain has suffered some parity errors.

3.141592653589793

How Many Decimals of Pi Do We Really Need? - Edu News | NASA/JPL Edu

While world record holders may have memorized more than 70,000 digits of pi, a JPL engineer explains why you really only need a tiny fraction of that for most calculations – even at NASA.

www.jpl.nasa.gov

I am very bad at basketball but it helps me remember pi:

My 3 game averages is only 1 for 16

3 1 4 16

If I practice I can get:

3 game average up to 1 for 15 if I practice from 9 to 6:53 and I only have to practice 58 days every 98 days

3 1 4 15 9 2 653 58 98

Pi to 13 decimal places.

 

[JRH]

Gotta say BTU is my favourite arch enemy. Especially when mixed with anything electrical, ie electric heater with 2000w input power and 31415 BTU’s output.

How many fahrenheits you can heat 12 gallons of heavy water with the potential energy of 10 000 pound block of gold falling from a height of 1 US survey mile?

The correct answer to your question is 49 decibels……..
J.