What happens to the volume of a rising or sinking air parcel?

  • Consider a parcel of air at 1000mb

  • The parcel will exert 1000 mb of pressure to counteract the atmospheric pressure acting on the parcel

  • Recall that Pressure = Force/Area

  • If no energy is added or taken away from the parcel, then the force of the molecules bumping into the side of the parcel will be constant, i.e.,

  • Force = Pressure x Area = const