Abstract
Tsunami Squares is a computationally lightweight tsunami and inundation
simulator which utilizes a unique cellular automata technique. We make
modifications to the underlying algorithm which result in increased
accuracy and enhanced waveform resolution. These improvements leave
Tsunami Squares well suited for machine learning applications where
large pre-computed tsunami simulation databases are required. Previous
implementations relied heavily on a smoothing algorithm which acts as a
moving average applied to the water surface heights and velocities to
eliminate anomalies at every time step. Although this allowed the
simulation to function properly, it brings several unwanted effects such
as reduced wave detail and lowered energy. A solution is found by
shifting the location at which the water surface gradient is calculated,
reducing the amount of anomalies in the simulation, and thus lowering
the amount of smoothing needed by a factor of $\sim
10$. Also introduced is a new method to conserve energy locally,
compared to previous methods which reference a simulation-wide energy
calculation. We make comparison tests were made using the 2011 Tohoku
tsunami along with the 2010 Maule tsunami to demonstrate the
improvements made.