Trying to resolve a volume calculation

AI Thread Summary
The discussion revolves around calculating the volume of the atmospheric layer above sea level up to Flight Level 300 (30,000 feet) and subtracting the volume of land within that layer. The user approximates the Earth as a perfect sphere, calculating the volume of the sphere at sea level and at 30,000 feet, resulting in a volume difference of about 5.12x10^18 cubic meters. They express confusion over the volume of land above sea level, finding conflicting estimates, including one suggesting around 1 trillion cubic kilometers. The user seeks clarification and assistance in resolving these discrepancies in their calculations.
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Hi all, I've made errors in my calculations and need help.

I'm trying to calculate the volume of a layer above sea level to the height of Flight Level 300 i.e. 30,000 feet. Next, I want to subtract the volume of land within that layer. Here are my calculations.
Purely for the sake of my calculations, I'll treat the earth as a perfect sphere, and I'll round 30,000feet to 10,000m.

1. The radius of the sphere of earth at sea level is approx 6,378,000m. That would make its volume approximately 1.08675x10^21 cu.m.

2. From the height of FL300 (30,000ft) or (rounded) 10,000m the radius increases to about 6,388,000m. The total volume of the larger sphere would be 1.09187x10^21cu.m

3. Subtracting one from the other leaves the volume of the layer at about 5.12x10^18cu.m.

4. There is no landmass above FL30. I've googled the total volume of all land masses within that layer (i.e. above sea level) and the only answer I can find (in 3 places) is 1 trillion cu.km or around 1x10^21cu.m. If this is true, then my calculations are badly wrong.

I would love your help with this? And thank you in advance.
 
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narrator said:
I've googled the total volume of all land masses within that layer (i.e. above sea level) and the only answer I can find (in 3 places) is 1 trillion cu.km or around 1x10^21cu.m.
I find a different estimate, 125,109,600 km3, here.
 
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Hill said:
I find a different estimate, 125,109,600 km3, here.
Thanks for that. I found the Wiki article that your link refers to. Excellent! Much appreciated!
 
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