The discrepancy of tsunami arrival time between the tsunami simulation and the real observation has been widely recognized since the 27 February 2010 Chile tsunami and the 11 March 2011 Japan tsunami. The effect of ocean-water compressibility and earth elasticity on tsunami propagation speed was analyzed on the basis of a multilayered earth model. A correction term of these effects was introduced to ordinary linear long wave equations. Calculated waveforms with the correction were quantitatively compared with observed ones of the two tsunamis. The accuracy of far-field tsunami simulation was significantly improved without any arbitrary parameter.
