Copenhagen Climate Change Petition

[Repwoc]

mass scale nuclear fission
someone might get nuclear fission working on earth

I guess you mean fusion. Fission is what we have now.

Negative buoyancy below a certain depth

How does that work?

 

[m100]

I did mean fusion, I was sure I wrote fusion, but I didn't it's been '20 years away' according to 'experts' for the last four decades.

As for negative buoyancy its something you strive to avoid as a scuba diver and why lifting shipwrecks can be a PITA.

Something will only float if it displaces a mass of water equal to or greater than the mass of the object. In the case of a log, if the wood fibres crush, and the air within the tree is compressed, the volume of water displaced will reduce and the object will sink.

So, place a log on the surface of the sea and it will float, artificially assist a log to 3 metres down and it will rise to the surface because the fibres won't be crushed by the water pressure, but artificially assist a log to hundreds of metres down and it will sink, and stay there.