Does being under water provide any protection from a asteroid? Does being under or on water provide any protection from an asteroid hitting the opposite side of the Earth over being in or on land or in air? Why? 

Will the shock wave follow the curvature of the Earth through the oceans?

I'm trying to go with the worst case survivable scenario.

Related:


  This is from a broad question that I am breaking up in 3 questions. Feel free to edit.


Scenario 3. In a submarine or capsule underwater?

Does being in the air provide any protection from an asteroid?
No. It depends on the severity. Water would be worse. If an asteroid hit in the ocean we would experience tsunamis the size we get from large magnitude earthquakes. The displacement of the water would be massive. It would also cause things like swimming pools sloshing around, common to the videos you see of hotels from the 2011 Japan earthquake. If it hit on the opposite side of the Earth, land would still be a better spot. Tsunamis can translate vast distances depending on the level of energy and surface deformation they create. Being in a submarine?  Again, no. A tsunamis can pass under boats. However, impact from an asteroid vs sea floor deformation from earthquakes are different functions. The submarine one, would require someone with a little more expertise.