The torques of the frictional forces on the bottoms of the seas are calculated in an approximate inertial system and not in the corotating system used hitherto. In this way, the loss of rotational energy of the Earth – corresponding to the mean torque – can be compared with the value obtained from astronomical observations. The calculations are based on velocities which are computed by numerical integrations of the hydrodynamical equations. Initial results are presented for the North Sea, the Bering Sea and rough models of theworld ocean.