Pulsed sounds are measured in terms of their total energy, rather than just their pressure or intensity.
Pressure and power measures are difficult to interpret for a brief pulse since they depend on the averaging
time. Energy is proportional to the time integral of the squared pressure, described in the units µPa-s. For
brief pulses, energy in dB re: µPa2-s is less than peak squared pressure values in dB µPa2
. As others have warned, better standardization of measurement methods for pulsed underwater sounds is urgently needed to permit meaningful comparisons (Greene 1995).