As far as I know, the total pressure changes across a shock wave. How is this possible if you are in the atmosphere and atmospheric pressure isn't changing? Is energy lost due to entropy in generated through a shock wave, and therefore a loss of pressure occurs?
The scalar pressure changes across a shock wave in a collisional fluid because of the conservation of momentum and energy flux. This is one of the conservation equations in the Rankine-Hugoniot relations which govern the thermodynamics of shock waves.