Diffusion is the idea that when a solute enters an area with a lower concentration than the solute, it will mix into the area. So the skunk odor has a higher solute concentration then the atmosphere it's released into, so when it is released it will diffuse across a wider area in order to try and level out the level of concentration. This means it can be smelt from further away. <span />
Even if remains at constant temperature, while ascending to the surface of the lake Jacques lung pressure will increase if he hold its breath. Thats because the pressure of water weakens and the pre-hold breath in lungs will expand as he rises. This can cause serious lung damage and drowning is possible.
